The Basics of Health, Wellness, and Fitness

🧭 Overview

🧠 One-sentence thesis

Health and wellness are distinct but overlapping concepts—health encompasses complete physical, mental, and social well-being (not just absence of disease), while wellness is a holistic compilation of eight controllable dimensions that enhance quality of life, both of which are shaped by social determinants that create health disparities.

📌 Key points (3–5)

• Health vs. wellness: Health is a state of complete well-being (WHO definition); wellness is a holistic set of dimensions that enhance quality of life and help reach full potential.
• Eight dimensions of wellness: Emotional, physical, occupational, social, spiritual, intellectual, environmental, and financial—most aspects are controllable.
• Controllable vs. uncontrollable health factors: We cannot control genetics, race/ethnicity, age, or sex, but we can control physical activity, diet, substance use, and social support.
• Common confusion: Health and wellness are often used interchangeably, but wellness is more about controllable dimensions that influence overall health.
• Social determinants of health: Five domains (healthcare access/quality, neighborhood/built environment, social/community context, economic stability, education access/quality) create disparities by affecting exposure, vulnerability, and consequences.

🏥 Defining health and wellness

🏥 What health means

Health: "a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity" (World Health Organization).

• Older definitions (e.g., Oxford 2013) defined health narrowly as "free from illness and injury."
• The WHO definition is more holistic: it includes mental and social well-being, not just physical absence of disease.
• Through this lens, wellness appears to be a component of health.

🌟 What wellness means

Wellness: a holistic compilation of dimensions that enhance one's quality of life and enable them to reach their full potential.

• Wellness is about controllable aspects that influence overall health.
• It is not a single state but a collection of interconnected dimensions.
• Example: Someone may be free from disease (health) but still have low wellness if they lack social support or financial stability.

🔄 How they relate

• Health and wellness are depicted as overlapping circles in the excerpt.
• Wellness influences overall health.
• Don't confuse: Health is the broader state; wellness is the set of dimensions we can actively improve.

🎯 The eight dimensions of wellness

😊 Emotional wellness

• The ability to deal with stressors and life's ups and downs in an effective and positive way.
• It's about coping skills and resilience, not just feeling happy all the time.

💪 Physical wellness

• The ability to care for one's physical body.
• Includes physical activity, fitness, exercise, nutrition, substance use, and disease prevention.
• Example: Choosing to exercise regularly and eat a balanced diet supports physical wellness.

💼 Occupational (vocational) wellness

• Wellness surrounding satisfaction with your career or job.
• Beyond financial implications: includes job satisfaction, job safety, and work-life balance.
• Can be linked to financial wellness but has other considerations.

💰 Financial wellness

• The ability to live within your means, set goals, and plan for the future.
• Two sides: income and spending.
• Don't confuse: Higher income ≠ automatically higher financial wellness; someone earning less but spending wisely may have higher financial wellness than someone earning more but overspending.

🧠 Intellectual wellness

• The desire and ability to learn and inquire.
• Individuals with high intellectual wellness are lifelong learners: inquisitive, curious, and creative.
• Traditional education is one way, but not the only way—using available resources to expand knowledge counts.

🤝 Social wellness

• Having good interpersonal relationships.
• Quality over quantity: positive relationships with friends, family, and significant others.
• Ability to depend on your social group when needed and be available for others.

🕊️ Spiritual wellness

• Believing in something that gives your life value and meaning.
• Can be related to religion, but does not need to be.

🌍 Environmental wellness

• The relationship one has with the environment and how it impacts health and well-being.
• Two aspects: what your environment provides (clean water, clean air) and how you care for it (e.g., recycling).

⚖️ Controllable vs. uncontrollable health factors

🚫 Uncontrollable factors

Factors we cannot control:

• Genetics (genetic disorders caused by abnormalities in genetic material)
• Race and ethnicity (some ethnicities at increased risk for certain diseases)
• Age (risk of certain diseases differs by age)
• Biological sex (risk differs by sex)
• Unknown environmental exposures (pollutants in air/water)
• Random events (injury/disability from extreme weather or others' behaviors)

✅ Controllable factors

Factors we can control:

• Physical activity level
• Balanced diet
• Abstaining from illicit drug use, smoking, and alcohol
• Practicing safe sex
• Surrounding ourselves with emotionally supportive people
• Safe online practices

Example: An individual cannot change their genetic predisposition to a disease, but they can choose to exercise and eat well to reduce other risk factors.

🌐 Social determinants of health

🌐 What they are

Social determinants of health: "the conditions in the environments where people are born, live, learn, work, play, worship, and age that affect a wide range of health, functioning, and quality-of-life outcomes and risks" (U.S. Department of Health and Human Services).

• These determinants influence health and wellness.
• They create health disparities: differences in health outcomes across populations.
• Broken into 5 domains.

🏥 Healthcare access and quality

• Your ability to receive proper medical treatment in a timely manner.
• Factors: physical distance from a hospital, health insurance, financial means, and health literacy.

Health literacy (individual): "the degree to which individuals have the ability to find, understand, and use information and services to inform health-related decisions and actions for themselves and others."

Health literacy (organizational): "the degree to which organizations equitably enable individuals to find, understand, and use information and services to inform health-related decisions and actions for themselves and others."

Example: Someone living far from a hospital or lacking insurance may delay seeking care, worsening health outcomes.

🏘️ Neighborhood and built environment

• How safe the area is where someone spends most of their time (live, work, play, learn, worship).
• Considerations:
  • Is it safe to be active? (sidewalks, parks, low crime)
  • Environmental exposures (air and water quality)
• Individuals with low income and racial/ethnic minorities have greater likelihood of living in places that pose safety and health risks.

Example: A neighborhood with high crime and no sidewalks discourages physical activity, lowering physical wellness.

👨‍👩‍👧‍👦 Social and community context

• Families, schools, places of worship, and other community members positively or negatively impact overall well-being, health, and safety.
• Individuals are influenced by the choices, beliefs, and actions of their families.
• For children, adolescents, and young adults: role models and good support systems increase exposure to safe environments and decrease vulnerability to dangerous/unhealthy behaviors.

Example: A young person with supportive mentors is less likely to engage in risky behaviors.

💵 Economic stability

• Economic stability influences health when basic needs cannot be met.
• Beyond basic needs: affects likelihood of attending regular doctor's appointments and seeking medical attention.
• Financial strain causes added stress, increasing risk of various health outcomes.

Example: Someone unable to afford healthy food may have poorer nutrition, affecting physical wellness.

🎓 Education access and quality

• Higher education level typically linked to higher income and better health.
• Children who experience discrimination, have disabilities, or are from low-income households are more likely to struggle with math/reading and less likely to attend college or graduate high school.
• Beyond income: health literacy and information literacy are important for accessing health information and appropriate healthcare.

Don't confuse: Education access is not just about attending school; it's also about the quality of education and how literacy (including health literacy) affects health outcomes.

📊 How social determinants create disparities

📊 Three pathways

Disparities within the five domains influence health outcomes in different ways:

Pathway	What it means
Exposure	Different levels of exposure to various environments or situations that could impact health
Vulnerability	Different levels of vulnerability to certain health outcomes
Consequences	Different consequences of the same conditions

Example: Two people with the same genetic risk for a disease may have different outcomes if one lives in a neighborhood with clean air and access to healthcare, while the other does not.

🧭 Overview

🧠 One-sentence thesis

Successful behavior change depends on believing in your ability to change (self-efficacy), perceiving control over outcomes (locus of control), progressing through stages from contemplation to action, and setting goals that are specific, measurable, attainable, realistic, and time-framed (SMART).

📌 Key points (3–5)

• Self-efficacy is your belief in your own capability to achieve a goal; it's influenced by past performance, vicarious experience, social persuasion, and physiological state.
• Locus of control describes whether you see outcomes as within your control (internal) or determined by external forces (external); internal locus supports behavior change.
• Stages of Change Model maps the journey from not thinking about change (precontemplation) through contemplation, preparation, action, maintenance, and termination—with relapse possible at any stage.
• Common confusion: Action vs. maintenance—action means you've started the behavior, but maintenance requires sustaining it for at least six months.
• SMART goals increase success by ensuring goals meet five criteria: Specific, Measurable, Attainable, Realistic, and Time-frame specific.

🧠 Self-Efficacy: Belief in Your Ability

🔍 What self-efficacy means

Self-efficacy: "People's judgments of their capabilities to organize and execute courses of action required to attain designated types of performances."

• In simpler terms: the belief you have in yourself regarding a specific goal or situation.
• It's not general confidence—it's situation-specific belief in your ability to succeed.
• Your belief in your ability to make a change directly impacts whether the change actually happens.

🛠️ Four factors that shape self-efficacy

According to Bandura's Self-Efficacy Theory, four factors enhance or hinder self-efficacy:

Factor	What it means	Impact
Past performance	Previous successes or failures in the same or similar situations	Strongest influence on self-efficacy
Vicarious experience	Watching others succeed or fail	Shapes your expectations
Social persuasion	Encouragement or discouragement from others	Can boost or undermine confidence
Physiological state	Your physical/emotional condition	Affects perceived capability

• Example: If you successfully walked three times last week, your self-efficacy for walking this week is higher.
• Don't confuse: Self-efficacy is not fixed—it changes based on these four factors and can be strengthened over time.

🎯 Locus of Control: Who's in Charge?

🔄 Internal vs. external locus of control

Locus of control: how an individual perceives their personal level of control or lack thereof over situations.

Two ends of the continuum:

• Internal locus of control: You take personal responsibility for outcomes, both good and bad; you see yourself as making things happen.
• External locus of control: You believe outcomes are largely out of your control; you see things as happening to you or as a result of fate.

💡 Why it matters for behavior change

• Someone with a strong internal locus of control is more likely to believe they can make a change happen.
• Someone with an external locus may feel that success or failure is beyond their influence.
• For behavior change, an internal locus of control is generally more beneficial because it supports taking action and responsibility.

Example: An internal-locus person who misses a workout thinks, "I need to plan better." An external-locus person might think, "Things just got in the way—nothing I could do."

🪜 Stages of Change Model: The Journey

📍 The five stages (plus termination)

The Transtheoretical Model (Stages of Change Model) breaks behavior change into distinct stages:

Stage	What's happening	Timeline/markers
Precontemplation	No intent to change; benefits don't outweigh downsides	May last indefinitely; person may not see need to change
Contemplation	Thinking about change; benefits starting to outweigh downsides	Planning to change within 6 months; gathering resources
Preparation	Close to taking action; may be making small attempts	Within a month of full action; taking initial steps
Action	Actively making the change; benefits clearly outweigh downsides	Started the behavior; committed but relapse is possible
Maintenance	Sustained the behavior for at least 6 months	Continuing the behavior consistently
Termination	Behavior is part of lifestyle; unlikely to relapse	Fully integrated; permanent change

🔁 Understanding relapse

• Relapse is not a stage, but it's common—people can fall back to a previous stage at any point.
• The excerpt emphasizes: acknowledge the relapse, don't dwell on it, forgive yourself, give yourself credit for what you've accomplished, and move forward.
• Example: Someone exercising three days a week suddenly stops—they've relapsed from action or maintenance back toward preparation or contemplation.

🚶 Example progression

• Precontemplation: "I know activity is important, but the time and discomfort aren't worth it to me."
• Contemplation: "Maybe I should start walking. Let me schedule a doctor's appointment and look into shoes."
• Preparation: "I went for one walk this week—not three yet, but I'm starting."
• Action: "I've been walking three times a week for the past month."
• Maintenance: "I've walked three times a week for six months straight."
• Termination: "Walking is just part of my routine now; I don't even think about skipping it."

🎯 SMART Goals: Making Change Stick

🧩 What SMART stands for

SMART criteria: making sure a goal is Specific, Measurable, Attainable, Realistic, and Time-frame specific.

• The excerpt notes that vague goals often lead to relapse; SMART goals increase the likelihood of success.

📋 Breaking down each criterion

Letter	Criterion	What it means	Example
S	Specific	Clearly state what you want to achieve	Not "save money" but "save $100 a week by not eating out"
M	Measurable	Track progress with concrete units	Dollars, pounds, time—countable metrics
A	Attainable	You have access to the resources needed	Can you realistically access what's required?
R	Realistic	Expectations aren't too big to start	The amount/frequency fits your current circumstances
T	Time-frame specific	Set a start-to-end deadline	"Save $400 by the end of the month"

✅ Why SMART works

• Vague goal: "I want to exercise more." (No way to measure, no deadline, unclear what "more" means.)
• SMART goal: "I will walk for 30 minutes, three days a week, for the next month." (Specific activity, measurable frequency and duration, attainable if you have time and access, realistic for a beginner, time-framed to one month.)

Don't confuse: Attainable vs. realistic—attainable asks "Do I have the resources?" while realistic asks "Is the expectation reasonable given my situation?"

🔗 How the concepts work together

🧩 The change ecosystem

• Self-efficacy fuels your belief that you can succeed.
• Locus of control determines whether you see yourself as capable of driving the outcome.
• Stages of Change map where you are and what comes next.
• SMART goals provide the concrete roadmap for moving through the stages.

Example: Someone with high self-efficacy and internal locus of control in the preparation stage sets a SMART goal ("Walk 20 minutes, twice a week, for two weeks") and moves into action—then maintains the behavior and eventually reaches termination.

🔄 Reflection and adjustment

• The excerpt recommends weekly reflection on your SMART goal:
  • What progress have you made?
  • What barriers did you encounter?
  • What strategies worked or didn't work?
• Reflection helps you learn from barriers and relapse without shame, supporting long-term success.

🧭 Overview

🧠 One-sentence thesis

Physical activity and exercise differ primarily by intent—exercise is planned movement aimed at improving or maintaining specific fitness components, while physical activity encompasses all bodily movement that increases energy expenditure.

📌 Key points (3–5)

• Physical activity vs. exercise: All exercise is physical activity, but not all physical activity is exercise; the key difference is intent and structure.
• Two types of fitness components: Health-related components (essential for maintaining health) and skill-related components (important for sports but not required for optimal health).
• Minimum recommendations: Adults should aim for at least 150 minutes of moderate-intensity or 60 minutes of vigorous-intensity aerobic activity per week, plus strength and flexibility training.
• Common confusion: You don't need elite-level fitness (marathon runner, gymnast flexibility) to maintain health—sufficient levels in each component are enough.
• Wide-ranging benefits: Physical activity provides immediate benefits (better sleep, reduced anxiety) and long-term benefits (reduced disease risk, improved bone health).

🔍 Distinguishing physical activity from exercise

🏃 Physical activity definition

"Any bodily movement produced by the contraction of skeletal muscles that results in a substantial increase in caloric requirements of resting energy expenditure."

• Includes any movement that makes muscles contract and burns more energy than resting.
• Broad category that covers work, leisure, and intentional exercise.
• Example: splitting wood, construction work, or shoveling snow all count as physical activity.

🎯 Exercise definition

"A type of physical activity consisting of planned, structured, and repetitive bodily movement done to improve or maintain one or more of the components of physical fitness."

• The distinguishing feature is intent: you're specifically trying to improve or maintain fitness.
• Must be planned, structured, and repetitive.
• Example: Going on a hike because you love nature = physical activity; going on a hike to improve cardiovascular endurance or hit a step goal = exercise.

🔄 The relationship between them

• Think of exercise as a subset of physical activity.
• All exercise is physical activity, but not all physical activity is exercise.
• The same activity can be either, depending on your goal.

💪 Components of fitness

🏥 Health-related components (5 total)

These are essential for maintaining health, though you don't need elite levels to be healthy.

Component	Definition	Health importance
Cardiovascular fitness	The ability of the body to transport oxygen	Essential, but you don't need marathon-level fitness
Muscular strength	The ability of skeletal muscles to overcome resistance	Important for daily tasks
Muscular endurance	The ability of skeletal muscle to resist fatigue	Supports sustained activity
Flexibility	The available range of motion at a joint	Needed for movement, but not dancer-level
Body composition	The ratio of fat vs fat-free mass	Affects overall health

⚡ Skill-related components (6 total)

These benefit athletic performance but are not considered essential for optimal health.

Component	Definition
Speed	The ability to move quickly from one point to another
Agility	The ability to move quickly with changes in direction
Power	The ability to overcome a force at speed
Coordination	The ability to move with control and accuracy
Balance	The ability to maintain equilibrium when stationary or moving
Reaction time	The time it takes to respond to a stimulus

🎯 Don't confuse fitness levels with health requirements

• Having sufficient fitness in health-related components maintains health.
• You don't need superior or high levels to be healthy—that's optional based on personal goals.
• Example: You need enough cardiovascular fitness for health, but becoming a marathon runner is a choice, not a requirement.

📋 Exercise recommendations for healthy adults

🫀 Aerobic exercise minimums

For adults aged 18-65:

• Moderate intensity: At least 150 minutes per week (example: 30 min × 5 days)
• OR vigorous intensity: At least 60 minutes per week (example: 20 min × 3 days)
• Aerobic exercise raises heart rate and breathing rate.

Breaking it down:

• If you can't complete 30 or 20 minutes in one session, break it into multiple 10-minute sessions (or shorter if necessary).
• The goal is eventually to complete in one session.
• Remember: something is always better than nothing (in the absence of contraindications).

🏋️ Strength training minimums

• Participate in activities that increase muscular strength and/or endurance 2-3 times per week.
• Examples: lifting weights, resistance bands, bodyweight exercises.
• Important: Allow 48 hours rest between resistance training sessions for the same muscle group.

🧘 Flexibility training minimums

• Participate in flexibility activities 2-3 times per week.
• Examples: stretching, yoga.

⚠️ Understanding contraindications

Contraindication: when the risk of exercise is greater than the benefit.

• Sometimes there is too much risk for someone to exercise.
• Health screening (like PAR-Q) is important to identify contraindications.
• Check with your doctor if unsure, especially before starting a new program.

🎯 Context matters

• These are minimum guidelines for general health and wellness.
• Individual goals may require more (e.g., high-level athletes, weight loss goals).
• It's okay to build up to these recommendations gradually.
• Start where you are comfortable.

🌟 Benefits of physical activity

⚡ Immediate benefits (all adults)

• Improved sleep quality
• Reduced anxiety
• Reduced blood pressure

🛡️ Long-term benefits (adults under 65)

Disease risk reduction:

• Depression and dementia
• Heart disease and stroke
• Type 2 diabetes
• Eight types of cancer (bladder, breast, colon, endometrium, esophageal, kidney, lung, stomach)

Other improvements:

• Reduced risk of weight gain
• Improved bone health
• Reduced risk of falls

👶 Benefits for children

• Improved attention and memory
• Better muscular strength and endurance
• Improved blood sugar levels and bone strength
• Better aerobic fitness and blood pressure
• Reduced risk of depression
• Reduced risk of chronic diseases (obesity, type 2 diabetes)
• Helps regulate body weight and reduce body fat

👴 Additional benefits for older adults (65+)

All the benefits listed for younger adults, plus:

• Reduced risk of falls
• Helps older individuals live independently longer

🤔 Reflection point

The excerpt encourages noting which benefits you were already aware of versus those that were new information—this highlights how extensive the benefits are beyond what most people realize.

🧭 Overview

🧠 One-sentence thesis

Proper nutrition requires consuming roughly 50 different nutrients—both essential (which the body cannot make) and non-essential (which it can)—in appropriate amounts through macronutrients (carbohydrates, protein, fat, water) and micronutrients (vitamins and minerals) to sustain basic body functions and support health.

📌 Key points (3–5)

• Essential vs. non-essential nutrients: Essential nutrients must be consumed because the body cannot produce them in sufficient quantities; non-essential nutrients can be made by the body, but dietary intake is still often needed.
• Macronutrients provide energy and structure: Carbohydrates (4 Cal/g), protein (4 Cal/g), and fat (9 Cal/g) supply calories and perform vital roles; water is calorie-free but critical for survival.
• Micronutrients support body processes: Vitamins and minerals are needed in small amounts but are crucial for metabolism, immunity, bone health, and cellular function.
• Common confusion—calories: A "Calorie" on food labels is actually a kilocalorie (1,000 calories); calories measure energy from food and energy expenditure, and are necessary for life.
• Quality matters more than quantity: Whole grains, vegetables, fruits, lean proteins, and unsaturated fats are superior to refined carbohydrates, added sugars, processed meats, and trans fats.

🍽️ What nutrients are and why we need them

🧪 Definition of nutrients

Nutrients: chemical substances required by the body to sustain basic functions, optimally obtained by eating a balanced diet.

• There are roughly 50 different nutrients.
• Nutrients fall into two categories: essential and non-essential.

🔑 Essential nutrients

Essential nutrients: nutrients we need to consume because we cannot make sufficient quantities fast enough or at all on our own.

• The majority of nutrients are essential.
• We must prioritize consuming these through diet.
• Example: Most vitamins and minerals are essential.

🔄 Non-essential nutrients

Non-essential nutrients: nutrients the body can make on its own.

• "Non-essential" does not mean unimportant—it only means the body can synthesize them.
• The body may not produce enough to meet all needs, so dietary intake is still beneficial.
• Example: Vitamin D is non-essential, yet many people are deficient in it.
• Don't confuse: "Non-essential" with "unnecessary"—both types are vital for health.

⚡ Calories: energy measurement and needs

📏 What a calorie is

Kilocalorie (Calorie): the amount of heat needed to raise the temperature of 1 liter of water by 1°C.

• The term "Calorie" on food labels = 1 kilocalorie = 1,000 calories.
• Calories measure energy from food and energy expended by the body.
• Everything the body does—breathing, digesting, exercising—requires energy from calories.

🔢 Calories per gram of macronutrient

Macronutrient	Calories per gram
Carbohydrates	4 Cal/g
Protein	4 Cal/g
Fat	9 Cal/g
Alcohol*	7 Cal/g

*Alcohol is not a nutrient but does provide calories.

📊 Daily calorie recommendations

• Males (19–30 years): ~2,400 Cal/day on average.
• Females (19–30 years): ~2,000 Cal/day on average.
• Recommendations decrease slightly with age.
• Important: True needs are highly individualized and depend on activity level, body size, and other factors.

🍞 Macronutrients: nutrients needed in large amounts

🌾 Carbohydrates

Carbohydrates: macronutrients whose primary function is to provide energy; they are broken down and converted to glucose.

Roles:

• Primary energy source for the brain, nervous system, blood cells, and muscles during exercise.
• Aid in synthesis of nonessential amino acids.
• Stored as glycogen in muscle and liver.

Types:

• Complex carbohydrates: starches (grains, potatoes, legumes) and high-fiber foods (whole grains, some vegetables and fruits).
• Simple carbohydrates: single and double sugar molecules found in fruits, milk, and added to sweets and beverages.

Whole grains vs. refined grains:

Whole grains	Refined grains
Contain bran, endosperm, and germ	Only endosperm remains
High in fiber, vitamins, minerals	Lower in fiber and nutrients
Examples: oats, quinoa, brown rice, whole-grain bread	Examples: white bread, white rice, regular pasta

Glycemic index:

• Measures how quickly foods raise blood glucose.
• High glycemic index: fast rise (simple carbs, starches).
• Low glycemic index: slower rise (complex carbs, especially high-fiber).

Fiber:

• A non-digestible carbohydrate that slows blood glucose rise and aids digestion.
• Over 90% of females and 97% of males do not meet recommended fiber intake.
• Found in vegetables, fruit, and whole grains.

Added sugar:

• Most adults consume more than recommended (<10% of daily calories).
• Main sources: beverages (soda, juice, sweetened drinks) and desserts.

Recommendation: 45–65% of total daily calories from carbohydrates, emphasizing whole grains, vegetables, and fruit.

🥩 Protein

Protein: macronutrients that provide energy (4 Cal/g) and serve as key structural components of the body.

Roles:

• Structural: blood plasma proteins, hemoglobin, coagulation factors, cell membranes, bone, muscle.
• Functional: enzymes, some hormones, antibodies.
• Regulation: water balance and pH balance.
• Critical for growth and repair.

Amino acids:

• Proteins are made of 20 amino acids.
• 9 are essential (must be consumed).
• 11 are non-essential (body can make them).

Complete vs. incomplete protein:

Complete protein	Incomplete protein
Contains all 9 essential amino acids	Missing one or more essential amino acids
Animal products (meat, fish, eggs, dairy)	Most plant sources
Exception: soy is a complete plant protein	Vegetarians/vegans should eat varied plant proteins daily

Recommendation: 10–35% of total daily calories from protein; prioritize lean meats, fish, poultry, tofu, whole grains over processed meats (hot dogs, lunch meats).

🥑 Fat (Lipids)

Fats (lipids): macronutrients that provide energy (9 Cal/g), especially during rest and low-intensity activities, and support insulation, protection, and absorption of fat-soluble vitamins.

Types:

Type	Characteristics	Examples	Recommendation
Saturated fat	Solid at room temperature	Butter, cream, high-fat meats, coconut oil	<10% of daily calories
Unsaturated fat	Liquid at room temperature	Olive oil, canola oil, corn oil, sunflower oil	Trade some saturated for unsaturated
Trans fat	Created by adding hydrogen to unsaturated fats (hydrogenation)	Formerly in partially hydrogenated oils (banned in US in 2018)	As low as possible

Health note:

• Saturated and trans fats are linked to increased cardiovascular disease risk.
• Quality matters: saturated fat from quality meat is better than from burgers, tacos, and desserts.

Cholesterol:

• Dietary cholesterol is not strongly linked to blood cholesterol or cardiovascular disease.
• The 300 mg/day recommendation was removed in 2015.
• Most high-cholesterol foods (except eggs and shrimp) are also high in saturated fat.

Recommendation: 25–35% of daily calories from fat; <10% from saturated fat; minimize trans fats.

💧 Water

Water: a calorie-free macronutrient essential for survival, maintaining blood volume, cellular functions, and body temperature.

• Humans can survive ~50 days without food but only a couple of days without water.
• Total water intake includes plain water, other beverages, and water in food.

Adequate Intake (AI):

• Males (19–30 years): 3.7 L total (3.0 L from beverages).
• Females (19–30 years): 2.7 L total (2.2 L from beverages).

Dehydration effects:

• 3% body weight loss: impairs endurance in cool environments.
• 2% body weight loss: impairs endurance in hot environments.
• Also negatively impacts cognition.

Special note—hyponatremia:

• Ultra-endurance athletes must replenish electrolytes (especially sodium) lost in sweat.
• Hyponatremia = low sodium levels; symptoms include nausea, fatigue, confusion, muscle cramps, and in severe cases seizures or coma.

🧪 Micronutrients: nutrients needed in small amounts

💊 Vitamins

Vitamins: micronutrients that play roles in metabolism, act as antioxidants, assist with red blood cell production, and help maintain nerve, skeletal, and immune functions.

• There are 13 vitamins: A, C, D, E, K, and eight B vitamins.
• Water-soluble: absorbed into bloodstream (B vitamins, vitamin C).
• Fat-soluble: stored in liver and fatty tissue (A, D, E, K).

Non-essential vitamins:

• Vitamin D and K are the only non-essential vitamins.
• Vitamin D deficiency is very common (90% of adults are deficient).
• Vitamin D is important for bone health and calcium absorption.

Key principle:

• Vitamins are best absorbed from food, not supplements.
• Both deficiency and excess can cause negative health outcomes.

⚙️ Minerals

Minerals: micronutrients that aid growth, regulate body functions, and assist in energy release.

Two groups:

Major minerals (≥100 mg/day)	Trace minerals (<100 mg/day)
Calcium, phosphorus, magnesium, sodium, chloride, potassium	Iodine, copper, fluoride, iron, selenium, zinc

Important notes:

• Sodium: Average American consumes 3,400 mg/day; recommendation is ≤2,300 mg/day (1 teaspoon).
• Calcium: ~30% of males and 60% of females are deficient; important for bone density and osteoporosis prevention.
• Iron: Found in hemoglobin; transports oxygen. Iron deficiency affects ~10 million in the US (5 million have anemia). Heme iron (from meat, poultry, fish) is more easily absorbed than non-heme iron (from plants).

Key principle:

• Both deficiency and excess can cause harm.

📐 Dietary Reference Intakes (DRI)

📋 Understanding nutrient recommendations

Dietary Reference Intakes (DRI): reference values for nutrient intake in healthy people.

Four key terms:

Term	Definition
RDA (Recommended Dietary Allowance)	Average intake sufficient to meet nutritional needs of most healthy adults
AI (Adequate Intake)	Used when insufficient data exists for RDA; assumed adequate for most adults
EAR (Estimated Average Requirement)	Intake estimated to meet needs of 50% of healthy people
UL (Tolerable Upper Limit)	Maximum intake before negative effects of overconsumption are expected

⚠️ Fad diets and sustainable eating

🚫 What fad diets are

Fad diet: a weight loss plan that promises dramatic results over a short-term period.

Characteristics:

• Promise fast weight loss.
• Restrict or eliminate entire food groups.
• Use gimmicks and personal anecdotes.
• Fail to acknowledge physical activity.

Examples: Low-carb diets, ketogenic diets, Paleolithic diets, low-fat diets, vegan/vegetarian diets (when used as quick fixes), intermittent fasting (when misused), detox diets.

Exception—intermittent fasting:

• Evidence supports intermittent fasting as a treatment for type 2 diabetes.
• May promote weight loss, decrease insulin resistance, and influence hormones (leptin, adiponectin).

✅ Sustainable weight loss principles

• Monitor calorie intake.
• Consume moderate amounts of complex carbohydrates (fruits, vegetables, whole grains), protein, and fat.
• Use low-calorie-density foods to satisfy hunger.
• Choose foods that taste good and fit your lifestyle.
• Allow space for all foods you can safely consume and enjoy.

🏙️ Food deserts and access to nutrition

🗺️ What food deserts are

Food desert: a low-income community with limited access to affordable and healthy food.

USDA definition:

• Low income: poverty rate ≥20% or median family income <80% of state/metro median.
• Low access:
  • Urban: ≥500 people or 1/3 of population live >1 mile from a large grocery store.
  • Rural: ≥500 people or 1/3 of population live >10 miles from a large grocery store.
• Vehicle availability is also considered.

Connection to social determinants of health:

• Food deserts are environmental conditions that affect health outcomes and quality of life.
• May contribute to diet-related and weight-related health consequences.

🧭 Overview

🧠 One-sentence thesis

Cardiovascular endurance—the body's ability to transport oxygen to working muscles—is essential for health and quality of life, and can be measured and improved through aerobic exercise.

📌 Key points (3–5)

• What it is: cardiovascular endurance is the ability to transport oxygen to working muscles via blood and hemoglobin.
• Why it matters: adequate cardiovascular fitness prevents a downward spiral where low fitness leads to less activity, which further decreases fitness; aerobic exercise reduces premature death risk, especially from cardiovascular disease.
• How the body responds: during exercise, heart rate, stroke volume, breathing rate, blood flow to muscles, and systolic blood pressure all increase to meet oxygen demand.
• How to measure intensity: target heart rate zones (calculated via Traditional or Karvonen methods) or the Talk Test help determine if you're exercising at moderate or vigorous intensity.
• Common confusion: resting heart rate vs. exercise heart rate—bradycardia (<60 bpm) at rest can indicate high fitness, but heart rate naturally rises during exercise; don't confuse resting standards with exercise targets.

🫀 What cardiovascular endurance means

🫀 Core definition

Cardiovascular endurance: the ability of the body to transport oxygen to working muscles.

• This is not just "having a strong heart" in isolation; it involves the heart, lungs, blood vessels, and blood working together.
• The excerpt emphasizes that non-athletes need at least a threshold level for health and quality of life, not just elite performance.

🩸 How oxygen gets delivered

• Oxygen is transported via blood throughout the body.
• The majority binds to hemoglobin found in red blood cells.
• We rely on oxygen to yield energy for bodily work (heart contraction, digestion, exercise).
• Example: when running, working muscles need more blood and oxygen; better cardiovascular fitness means the body can sustain that delivery longer.

💓 Key cardiovascular measures

💓 Heart rate (HR)

Heart rate: the number of times your heart contracts or beats every minute.

• Resting heart rate: typically 50–90 bpm.
• Bradycardia: heart rate less than 60 bpm; can indicate high fitness or, in some cases, a medical concern.
• Tachycardia: heart rate above 100 bpm; can occur during exercise, stress, or due to pathological reasons.
• Don't confuse: a low resting HR in a fit person is normal, but HR naturally rises during exercise.

🩺 Blood pressure

Blood pressure: the pressure put on the blood vessels by the blood traveling through them, caused by the pumping action of the heart.

• Measured in the brachial artery (arm).
• Expressed as two numbers: systolic/diastolic.
  • Systolic (top number): pressure during ventricular contraction.
  • Diastolic (bottom number): pressure during ventricular relaxation.
• Hypertension (high blood pressure) increases risk of heart attack or stroke.
• For borderline high blood pressure, physical activity, weight management, and nutrition can help prevent progression; always follow physician recommendations.

🫁 Breathing rate

• At rest: about 15 breaths per minute.
• During maximal exercise: can increase to 40–60 breaths per minute.
• Each breath also brings in a greater volume of air during exercise.

🏃 What happens during exercise

🏃 Cardiovascular changes from rest to exercise

At rest, the cardiovascular system operates at a steady pace; during exercise, demand increases dramatically.

Measure	At rest	During exercise
Heart rate	60–80 bpm	Increases
Stroke volume	Baseline	Increases (more blood per beat)
Blood to muscles	15–20% of output	Up to 80–85% at maximal exercise
Breathing rate	~15 breaths/min	Up to 40–60 breaths/min
Systolic blood pressure	Baseline	Increases

• Stroke volume: the amount of blood leaving the heart with each contraction; increases during exercise.
• The heart contracts more frequently and pumps more blood per beat.
• Blood flow patterns shift: dramatically more blood goes to working muscles.

🔄 Why these changes occur

• The body increases cardiovascular activity to deliver more oxygen to working muscles.
• Without sufficient oxygen delivery, you cannot maintain exercise intensity.
• Example: someone more cardiovascularly fit can sustain a running pace longer because their system delivers oxygen more efficiently.

📉 Why cardiovascular endurance matters

📉 The downward spiral of inactivity

• If someone is inactive and has very low cardiovascular endurance, even low-level activity becomes challenging.
• As fitness decreases, the person does less (avoids stairs, minimizes movement).
• This creates a cycle: less activity → lower fitness → even less activity.
• Example: everyday tasks like removing snow from a car or chasing a loose pet become difficult or risky.

💪 Benefits of aerobic exercise

Aerobic exercise: exercise that maintains or improves cardiovascular endurance (requires oxygen).

• Participating in aerobic activities decreases the chance of premature death from all causes, primarily cardiovascular disease.
• ACSM recommendations for healthy adults (18–65):
  • Minimum 150 min/week of moderate-intensity aerobic exercise (e.g., 30 min, 5 times/week), OR
  • 60 min/week of vigorous exercise (e.g., 20 min, 3 times/week).
• Don't confuse: the narrative of declining fitness is common but not inevitable—cardiovascular endurance can be improved.

🎯 Measuring exercise intensity

🎯 Target heart rate (THR) zones

Two main methods to calculate your target heart rate for exercise:

🧮 Traditional Method

1. Estimate age-predicted maximal heart rate: 220 – age = predicted HRmax (in bpm).
2. Multiply HRmax by a percentage to find your target range.
   • Moderate intensity: 64–<76% of HRmax.
   • Vigorous intensity: 77–95% of HRmax.
3. Example for a 20-year-old:
   • HRmax = 220 – 20 = 200 bpm.
   • Moderate THR = 200 × 0.64 = 128 bpm (lower end); 200 × 0.76 = 152 bpm (upper end).
   • Target range: 128–152 bpm.

Note: This is an estimation; a true HRmax requires a graded exercise test to maximal exertion, which is time-consuming and not always safe or practical.

🧮 Karvonen Method

Takes Heart Rate Reserve (HRR) into account: HRR = HRmax – HRrest.

1. Find predicted HRmax: 220 – age.
2. Measure resting HR (ideally first thing in the morning, or after 5 min of rest).
3. Calculate HRR: HRmax – resting HR.
4. Target HR = resting HR + (% intensity × HRR).
   • Moderate intensity: 40–<59% HRR.
   • Vigorous intensity: 60–<89% HRR.
5. Example for a 20-year-old with resting HR of 60 bpm:
   • HRmax = 200 bpm; HRR = 200 – 60 = 140 bpm.
   • Moderate THR = 60 + (0.40 × 140) = 116 bpm (lower); 60 + (0.59 × 140) = 143 bpm (upper).
   • Target range: 116–143 bpm.

Benefit: The Karvonen method accounts for cardiovascular fitness (via resting HR), not just age.

🗣️ Talk Test

A simple alternative to calculate intensity:

• Moderate intensity: you can talk conversationally but not sing (too out of breath to sing).
• Vigorous intensity: you cannot talk conversationally (too short of breath).

Don't confuse: the Talk Test is an estimation, not a precise measurement like THR.

📊 Assessing cardiovascular fitness

📊 Gold standard: VO2max test

VO2max test: assesses maximal aerobic or cardiovascular capacity—the maximal amount of oxygen an individual can consume during maximal cardiovascular exercise.

• Requires a metabolic cart and trained personnel.
• Often not practical or safe; less fit individuals may stop before reaching true VO2max.
• Because of these limitations, other valid and reliable tests exist.

📊 Practical test: Cooper 1.5-mile walk/run

Preparation:

• Ensure it is safe to participate (refer to PAR-Q).
• Warm up by walking or jogging.

Assessment:

• Walk, jog, or run 1.5 miles as quickly as possible (ideally on a track or measured flat distance).
• Record your time.
• Use provided charts (broken down by age and sex) to determine your cardiovascular fitness category (percentile rank).

Calculating estimated VO2max from your time:

1. Convert time from min:sec to a decimal.
2. VO2max = (483 / time) + 3.5.
3. Compare your result to the provided VO2max percentile charts.

Note: The Cooper test is one method; other options include the Astrand Bike Test and Harvard Step Test if the 1.5-mile test is not safe or practical.

---

Key Terms/Phrases

• Cardiovascular Endurance
• Oxygen transportation
• Heart Rate (Bradycardia, Tachycardia)
• Blood pressure (systolic, diastolic)
• Breathing rate
• Target Heart Rate
• Age predicted Maximum heart rate
• VO2max

🧭 Overview

🧠 One-sentence thesis

Resistance training improves muscular strength and endurance, which makes daily activities easier and helps prevent, manage, or slow the progression of chronic diseases like osteoporosis, obesity, and diabetes.

📌 Key points (3–5)

• Two main types of muscular fitness: muscular strength (ability to overcome resistance) vs. muscular endurance (ability to resist fatigue).
• Training differences: strength training uses heavy weight with low repetitions (1-5 reps at 60-80% of 1RM), while endurance training uses lighter weight with high repetitions (15-25 reps at ~50% of 1RM).
• Health benefits beyond performance: resistance training makes activities of daily living (ADLs) easier and is particularly beneficial for managing osteoporosis, obesity, and diabetes.
• Common confusion: don't confuse the different resistance training goals—hypertrophy (size), power (speed), strength (force), and endurance (fatigue resistance) require different training approaches.
• Minimum recommendations: full-body resistance training at least 2-3 times per week, with 48 hours rest between working the same muscle groups.

💪 Core definitions and concepts

💪 Muscular strength

Muscular strength: the ability of skeletal muscles to overcome resistance.

• This is about maximum force a muscle or muscle group can exert.
• Measured by one-repetition maximum (1RM)—the weight someone can correctly lift one time with maximal effort.
• Example: if someone can bench press 100 lb exactly once (and no more), their 1RM for bench press is 100 lb.

🔁 Muscular endurance

Muscular endurance: the ability of skeletal muscle to resist fatigue.

• This is about sustaining effort over repeated contractions or holding a contraction.
• Measured by tests like the YMCA bench press test (as many reps as possible at 30 reps/min), push-up test, or curl-up test.
• Example: completing 30 push-ups in a row demonstrates greater endurance than completing only 10.

🔍 Related training types (mentioned but not the focus)

Training type	Goal	Notes
Muscular power	Overcome force at speed	Beneficial for sport (e.g., Olympic lifts); beyond scope of this text
Muscular hypertrophy	Increase muscle size	Think bodybuilder; some variations from strength/endurance training

🏋️ Types of muscle contractions

🏋️ Dynamic contractions

• Cause joint movement.
• Two subtypes:
  • Concentric: muscle fiber shortens (e.g., raising the weight during a bicep curl).
  • Eccentric: muscle fiber lengthens (e.g., lowering the weight during a bicep curl).
• Many movements have both a concentric and eccentric phase.

🧱 Static (isometric) contractions

• No joint movement; muscle fiber length doesn't change.
• Example: holding a plank—muscles contract but joints don't move.

🩺 Why resistance training matters

🩺 Makes daily life easier

• Greater muscular strength and endurance make activities of daily living (ADLs) less stressful.
• ADLs are everyday tasks like carrying groceries, climbing stairs, or lifting objects.

🩺 Chronic disease prevention and management

The excerpt highlights three primary conditions where resistance training is particularly beneficial:

Condition	How resistance training helps
Osteoporosis	Weight-bearing exercise maximizes bone density early in life and prevents loss in middle-aged and older adults; especially important for females due to steeper bone density decrease after menopause
Obesity	Increasing muscle mass (part of fat-free mass) increases resting metabolic rate, leading to more energy expenditure at rest
Diabetes	Resistance training helps manage and slow progression (specific mechanisms not detailed in excerpt)

• Osteopenia: age-related loss in bone mass.
• Osteoporosis: severe decrease in bone mass leading to bone fragility and fractures.
• Fat-free tissue is more metabolically active than fatty tissue, so more muscle = higher resting energy expenditure.

📋 Training recommendations

📋 Frequency and recovery

• Minimum: full-body resistance training at least 2-3 times per week (when no contraindications exist).
• Recovery rule: avoid working the same muscle groups on back-to-back days; give 48 hours between working the same muscle group.
• You can train on consecutive days if you work different muscle groups.
• Example: train upper body Monday, lower body Tuesday, upper body Wednesday.

📋 Exercise selection

• First priority: multi-joint and compound movements (activating more than one muscle group).
  • Examples: chest presses, squats, back extensions, crunches.
• Secondary: single-joint movements are acceptable to add.
  • Examples: bicep curls, calf raises.

📋 Sets and repetitions

Sets: bouts of exercise.

Repetitions: the number of complete movements within a set.

For muscular strength:

• Relatively heavy weights (60-80% of 1RM).
• Low repetitions (1-5 reps).
• Rest 1-3 minutes between sets (depending on experience).

For muscular endurance:

• Relatively lighter weight (~50% of 1RM).
• High repetitions (15-25 reps).
• Less rest between sets.

Volume:

• Ideally 2-4 sets per muscle group (4 is more beneficial than fewer).
• Even a single set is beneficial—something is better than nothing.

📋 Intensity and 1RM

One repetition maximum (1RM): a weight someone can correctly lift (specific to the movement) with one effort.

• Resistance is expressed as a percentage of someone's 1RM.
• Example: if 1RM bench press is 100 lb, then 75% of 1RM = 75 lb.
• Assessing 1RM: warm up, select a comfortable starting weight, continuously add weight until reaching a weight that can only be moved once.
• Safety note: individuals with metabolic disease, pulmonary disease, or cardiovascular disease risk should use a 15 RM test instead of 1RM. Other conditions may also contraindicate heavy lifting.
• Alternative: multiple RM tests can estimate 1RM (e.g., if someone moves 80 lb for 8 reps and cannot do more, estimated 1RM is 100 lb).

🧪 Assessing muscular fitness

🧪 Strength assessments

• 1RM test: most common method; measures maximum weight lifted once with correct form.
• Multiple RM test: can estimate 1RM; safer for some populations.
• Hand grip strength test: can estimate overall muscle strength; uses a handgrip dynamometer.
  • Contraindication: individuals with elevated blood pressure or hypertension should NOT participate.
  • Protocol: standing with elbow extended or at 90 degrees, squeeze as hard as possible, complete 3 times per hand with 30 seconds rest, record highest score for each hand.

🧪 Endurance assessments

• Tests require repeated muscle contractions or holding a sustained contraction.
• YMCA bench press test: as many correct reps as possible at 30 reps/min; uses 80 lb for males, 35 lb for females.
• Push-up test: maximal correct repetitions without break or form breakdown.
  • ACSM version: males do standard push-ups; females do modified (knees on ground).
  • Adams et al. (2022) alternative: standard push-up norms for females 18-24 (acknowledges that many females can complete standard push-ups).
• Curl-up test: complete as many correct curl-ups as possible at metronome cadence (40 beats/min) up to 75 reps.
  • Distance: 12 cm for under 45 years; 8 cm for 45+ years.
  • Curl forward 30 degrees to move hands from first tape line to second.

🧪 Important testing notes

• Always warm up before assessments.
• Standards are broken down by sex due to physiological differences.
• Modified versions exist for those who struggle with standard protocols—a great starting point for training.

🧭 Overview

🧠 One-sentence thesis

Flexibility—the ability to move a joint through its complete range of motion—is essential for joint health, injury prevention, and daily function, and can be improved through regular stretching programs targeting all major joints.

📌 Key points (3–5)

• What flexibility is: the ability to move a joint through its complete ROM (range of motion); it is joint-specific, so improving one joint doesn't automatically improve another.
• Why flexibility matters: adequate flexibility prevents joint deterioration, supports daily activities, reduces injury risk, and improves balance and posture; both too little and too much flexibility can increase injury risk.
• How to improve it: regular stretching (at least 2–3 times per week) improves flexibility; transient gains appear immediately, chronic improvements in 3–4 weeks.
• Types of stretching: static (hold at end point), dynamic (controlled movement through ROM), ballistic (bouncing motion), and PNF (contract-relax with assistance).
• Common confusion: hypermobile (greater than normal ROM) vs. hypomobile (below normal ROM)—both extremes can increase injury risk, not just low flexibility.

🧩 Core concept: What flexibility is

🧩 Definition and scope

Flexibility: the ability to move a joint through its complete ROM (range of motion).

ROM (range of motion): the complete mobility possible at a joint.

• Flexibility is joint-specific: stretching one joint (e.g., hamstring) does not improve flexibility in another joint (e.g., shoulder).
• This is why a full-body flexibility program is necessary to achieve ideal ROM at all major joints.

🔧 What determines flexibility

According to the excerpt, flexibility at each joint depends on:

• Stretchability and distensibility of the joint capsule itself
• Muscle temperature (how warm the associated muscles are)
• Muscle viscosity
• Tightness of tissues, ligaments, and tendons around the joint
• Other factors: age, physical activity level, sex, previous injuries, and genetics

🎯 Why flexibility matters

🎯 Benefits of adequate flexibility

The excerpt lists many reasons adequate flexibility is important:

• Joint health: poor flexibility puts too much stress on joints, leading to deterioration and pain
• Athletic performance and daily activities (ADLs): adequate ROM supports both
• Injury and pain prevention: prevents arthritis, low back pain, muscle cramps
• Stability and balance: maintains or improves both
• Posture and relaxation: improves body position and provides relaxation
• Mobility: potentially improves impaired mobility

⚠️ The flexibility sweet spot

• Too little flexibility (hypomobile): below-normal ROM increases injury risk
• Too much flexibility (hypermobile): greater-than-normal ROM also increases injury risk due to decreased joint stability
• Don't confuse: the goal is not maximum flexibility, but adequate flexibility within a healthy range.

🏋️ Types of stretching

🧘 Static stretching

Static stretching: stretching to an end point and holding.

• How to do it: hold a single stretch for 10–30 seconds (or 30–60 seconds for older adults); the stretch should be felt but not painful.
• Why it's common: effective, safe, and easy to do; most commonly prescribed form.
• Recommendation: repeat each stretch 2–3 times for a total of 60 seconds combined.
• Example: reach toward your toes and hold the position without bouncing.

🏃 Dynamic stretching

Dynamic stretching: moving a joint through its ROM during the stretch.

• How it differs from static: instead of holding at an end point, you are in motion, aiming to increase the ROM covered with each movement.
• Key characteristics: movement is slow, controlled, and often exaggerated.
• Safety note: safe and effective but requires more coordination and balance.
• Example: controlled leg swings that gradually increase in range with each repetition.

⚡ Ballistic stretching

Ballistic stretching: uses a bouncing motion to create force behind the stretch.

• Risk: increased likelihood of injury; not commonly recommended for the general population.
• When it may be appropriate: when properly performed, may be effective for individuals in sports and activities that utilize ballistic movements.
• Don't confuse: ballistic (bouncing) vs. dynamic (controlled movement)—ballistic has higher injury risk.

🤝 Proprioceptive neuromuscular facilitation (PNF)

PNF stretching: typically involves an isometric contraction (muscle contraction without change in muscle length) phase, followed by a static stretch phase.

• How it works: the most common form is contract-relax stretching.
• Process: contract phase → stretch phase → (optional) repeat contract → second stretch phase (usually can stretch further).
• Assistance: typically involves the help of another person.
• Variations: there are different forms of PNF stretching.

📋 Stretching recommendations

📋 Frequency and timing

Aspect	Recommendation	Reason
Frequency	At least 2–3 times per week; up to 7 days per week is safe	Improves flexibility; more frequent is ideal
When to stretch	After exercise (after cool-down) while muscles are still warm	Stretching may temporarily decrease power and strength; doing it after avoids this issue
Warm-up requirement	Muscles must be warm before stretching	Raises muscle temperature and increases blood flow

📋 Technique and targets

• Target: major muscle-tendon units
• Repetitions: ideally repeat 2–4 times per muscle group
• Choice of technique: any of the four types can be used, but:
  • Static stretching is most common for most individuals
  • Ballistic is not ideal for everyone
  • Dynamic can be challenging for those lacking balance and coordination

⏱️ Timeline for improvement

• Transient improvements: can be seen immediately after stretching
• Chronic improvements: can be noted in as little as 3–4 weeks with consistent participation

🧪 Assessing flexibility

🧪 Why assessment is joint-specific

The excerpt emphasizes that flexibility is specific to each joint, so assessing one joint does not tell you about another. Two examples are provided:

🦵 YMCA V Sit and Reach Test

• What it assesses: hamstring and lower back flexibility
• Setup: tape on floor, ruler perpendicular to tape, sitting with feet 8–12 inches apart, heels touching tape line
• Procedure: palms down, hands parallel, reach forward slowly as far as possible, hold 2 seconds, repeat twice, record best score
• Note: fitness category standards differ by sex and age (percentile tables provided in excerpt)

💪 Apley's Scratch Test

• What it assesses: shoulder girdle ROM
• Part 1: raise one arm up, bend elbow, rotate outward, reach for opposite shoulder blade (or down spine)
• Part 2: put one arm behind back (low), bend elbow, rotate inward, reach up back toward opposite shoulder blade (or up spine)
• Evaluation: good mobility = ROM close to same on both sides and middle of shoulder blade is reached; limitation = ROM not close on both sides or middle of shoulder blade not reached
• Important: trunk should not rotate, no excessive lower back arching

Don't confuse: these two tests measure completely different joints and cannot substitute for each other.

🧭 Overview

🧠 One-sentence thesis

Body composition—the ratio of fat mass to fat-free mass—is a better indicator of health than body weight alone, and while both too much and too little body fat carry health risks, body composition is only one component of overall health and should not be the sole focus.

📌 Key points (3–5)

• What body composition measures: the ratio of fat mass to fat-free mass, typically expressed as body fat percentage; the remainder is bone, muscle, organs, water, etc.
• Why body fat percentage matters more than weight: two people with the same weight can have very different body compositions; excess fat tissue increases disease risk, while muscle mass does not.
• Common confusion—overweight vs. obese: overweight refers to body weight above the recommended range for height; obesity specifically means excess body fat (adipose tissue), which is the actual health concern.
• Essential vs. excess body fat: body fat is necessary for organ function, thermoregulation, and energy storage; essential fat is 3–5% in males and 8–12% in females, but both underfat and overfat conditions carry serious health risks.
• Limitations of common tools: BMI compares weight to height but does not assess body composition, making it less reliable for athletic individuals with higher muscle mass; waist circumference and other methods provide additional context.

🧬 What body composition is and why it matters

🧬 Definition and expression

Body composition: the ratio of fat mass to fat-free mass.

• Often expressed as body fat percentage: the percentage of total body that is fat tissue.
• The remainder (100% minus body fat %) includes bone, muscle, organs, teeth, connective tissue, and body water.
• Example: if someone has 25% body fat, 25% of their body is adipose tissue and 75% is everything else.

🩺 Why body fat is necessary

• Body fat is essential for:
  • Proper function of the nervous system, brain, heart, lungs, and mammary glands.
  • Protection of organs.
  • Thermoregulation (temperature control).
  • Energy storage.
  • Cell membrane structure.
• Essential fat (bare minimum for function):
  • Males: 3–5%
  • Females: 8–12% (higher due to reproductive needs, including uterus and breast tissue).

⚖️ Ideal body fat ranges

The excerpt provides age- and sex-specific ranges from Gallagher et al. (2000):

Sex	Age 20–39	Age 40–59	Age 60–79
Females	21–33%	23–34%	24–35%
Males	8–19%	11–21%	13–24%

• Below these ranges = underfat.
• Above these ranges = overfat or obese categories.

⚠️ Health risks of too much or too little body fat

⚠️ Risks of excess body fat

• Too much body fat is associated with chronic diseases:
  • Hypertension (high blood pressure).
  • Metabolic syndrome.
  • Dyslipidemia (unbalanced lipids/cholesterol).
  • Type 2 diabetes.
  • Cardiovascular disease, stroke, and heart attack.

⚠️ Risks of being underfat

• Being underweight increases risks including:
  • Stunted growth in children.
  • Respiratory and other infections.
  • Osteoporosis and bone fractures.
  • Cardiovascular disease.
  • Hormonal imbalance leading to fertility issues in both sexes.
  • Ovulation dysfunction and amenorrhea in females.
  • Depression.
  • Increased risk of premature death compared to healthy-weight individuals.

🔍 Don't confuse: weight vs. fat

• Body weight is "the mass or quantity of heaviness of an individual" (expressed in pounds or kilograms).
• Weight alone does not tell us body composition.
• Excess weight due to excess fat tissue is very different from excess weight due to muscle mass.
• The former increases disease risk; the latter is often a result of skeletal muscle training.
• Example: two individuals of the same sex, age, weight, and height can have very different body compositions.

📏 Tools for assessing body composition and their limitations

📏 Body Mass Index (BMI)

BMI: a tool that compares weight to height.

• Formula: BMI = Weight (in kg) / Height² (in meters).
  • To convert pounds to kg, divide by 2.2.
  • To convert inches to meters: 1 inch = 2.54 cm; 1 cm = 0.01 meters.
• BMI categories (kg/m²):
  • Underweight: <18.5
  • Normal: 18.5–24.9
  • Overweight: 25.0–29.9
  • Obesity: ≥30.0
• Health problems related to obesity increase after BMI of 25 kg/m².

⚠️ Limitations of BMI

• BMI does not assess body composition.
• Two individuals with the same BMI can have very different body compositions.
• Limitations are more pronounced in athletic individuals with higher-than-normal muscle mass.
• BMI is noninvasive and widely used, but it is important to understand its limitations.

📐 Waist circumference

• Why it matters: where body fat is stored affects health risk.
  • Visceral fat: fat around organs; linked to greater risk of metabolic syndrome.
  • Subcutaneous fat: fat under the skin; less risky than visceral fat.
  • Android obesity: excess fat in the abdominal/torso/trunk region; higher risk of chronic illnesses.
  • Gynoid obesity: excess fat in hips and thighs; lower risk than android obesity.
• How to measure:
  • Use a cloth tape directly above the iliac crest.
  • Do not compress the skin.
  • Take two measurements; if difference is ≤5mm, average them.
• Risk thresholds (CDC):
  • Males: >40 inches increases risk.
  • Females: >35 inches increases risk.

🔬 Methods to measure body fat

The excerpt describes several methods, each with different benefits (precision vs. convenience):

Method	How it works	Notes
Densitometry	Measures body density using body volume (via hydrostatic/underwater weighing or air plethysmography) and body mass (weight).	Highly accurate; requires more equipment.
DEXA (Dual-energy X-ray absorptiometry)	Uses a DEXA machine to measure bone density and overall body composition.	Highly accurate; requires specialized equipment.
Skinfold fat thickness	Uses skinfold calipers to measure thickness of skinfold fat.	Less expensive equipment; requires training for accuracy.
Bioelectrical impedance (BIA)	Uses electrical current to measure conductance through the body; water (mostly in fat-free mass) conducts electricity, so fat-free mass speeds conduction and fat mass slows it.	Requires little training; relatively inexpensive; can be handheld devices or bathroom scales.

🏥 Overweight, obesity, and the obesity epidemic

🏥 Definitions

Overweight: total body weight above the recommended weight for good health (based on height).

Obesity: "a complex disease involving having too much body fat."

• The concern with overweight is that it does not address body fat specifically—weight alone is not the problem.
• Obesity specifically refers to excess adipose (fat) tissue, which is the actual health concern.
• Don't confuse: excess weight due to muscle mass vs. excess weight due to fat tissue.

🌍 The obesity epidemic

• In the US (2022 CDC data):
  • Every state and territory had >20% adult obesity prevalence.
  • 19 states had 35–40% prevalence.
  • 3 states had >40% prevalence.
  • BMI is the tool used to categorize individuals as obese (BMI >30.0 kg/m²).
• Globally:
  • The World Health Organization estimates 115 million individuals in developing countries are dealing with obesity-related health issues.
• Why BMI is used for large-group data:
  • BMI is not the best measure of obesity, but it is beneficial for large-group data.
  • Results are more accurate with non-athletic individuals (athletes tend to have greater muscle mass).

⚖️ Balancing concern with well-being

• While the obesity epidemic is a serious problem, being overly concerned about body weight or body fat to the point that it is all-consuming is not healthy.
• Too much attention and concern may lead to:
  • Overtraining.
  • Disordered eating.
  • Relative energy deficiency in sport (RED-S).
• Body composition is only one indicator of disease risk; also consider:
  • Physical activity.
  • Nutrition.
  • Other areas of fitness.
  • Mental health.
• There is not one ideal body weight, shape, or size.

🧪 Practical considerations for assessment

🧪 When to assess body composition

• It can be reasonable for athletes to pay more attention to body composition than overall body weight or body size.
• However, if doing a body composition assessment will have a negative effect on an individual (mentally, emotionally, or behaviorally), the assessment should not be completed.

🧪 Optional assessment activities

The excerpt describes three optional activities:

1. BMI calculation and classification: use the formula and compare to standard categories.
2. Waist circumference measurement and classification: measure above the iliac crest, take two measurements, average if difference ≤5mm, and compare to risk criteria.
3. Bioelectrical impedance (BIA): follow instrument-specific instructions, then compare results to ideal body fat ranges or American Council on Exercise (ACE) standards.

ACE body fat % standards (excerpt provides partial data):

Sex	Essential Fat	Athletic
Females	10–13%	14–20%
Males	2–5%	6–13%

• Recommendation: no less than 10–13% body fat in females and 3% in males (The Cooper Institute, 2009).

🧪 Self-reflection

• Reflect on assessment results (if completed).
• Reflect on the importance of body fat and the risks of too little or too much.
• Consider lifestyle choices that promote healthy body composition.

🎯 Key takeaways

🎯 Body composition vs. body weight

• Body composition (ratio of fat mass to fat-free mass) is a better indicator of health than body weight alone.
• Weight does not take composition into account; it is simply mass or heaviness.

🎯 Essential vs. excess body fat

• Body fat is necessary for bodily function, but both too much and too little carry serious health risks.
• Essential fat is the bare minimum needed for function; ideal ranges vary by sex and age.

🎯 Tools and their limitations

• BMI is widely used but does not assess body composition; it is less reliable for athletic individuals.
• Waist circumference provides additional context about fat distribution and disease risk.
• Various methods exist to measure body fat, each with trade-offs between precision and convenience.

🎯 Obesity as a public health concern

• Obesity (excess body fat) is a major health concern in the US and globally, associated with many chronic illnesses.
• However, body composition is only one component of health; mental health, physical activity, and nutrition are also important.

🎯 Avoiding unhealthy focus

• Too much focus on weight and appearance can lead to overtraining, disordered eating, and RED-S.
• There is no single ideal body weight, shape, or size.
• Assessments should not be completed if they will have a negative mental, emotional, or behavioral effect.

🧭 Overview

🧠 One-sentence thesis

Stress, sleep, and self-care are interconnected aspects of health where understanding the body's stress response, sleep regulation mechanisms, and proactive self-care practices can help manage both acute and chronic stressors and promote overall well-being.

📌 Key points (3–5)

• Stress triggers a universal physiological response: regardless of the stressor's nature (major disaster or minor inconvenience), the body activates the same fight-or-flight systems involving the sympathetic nervous system and hormones like cortisol and adrenaline.
• Acute vs chronic stress: short-term (acute) stress is manageable, but long-term (chronic) stress continuously activates the stress response and can lead to serious health consequences including cardiovascular disease, impaired immunity, and fertility issues.
• Common confusion—distress vs eustress: not all stress is harmful; distress results from being overwhelmed, while eustress comes from challenging but worthwhile tasks (e.g., a presentation you'll feel good about afterward).
• Sleep is regulated by two mechanisms: circadian rhythms (24-hour light-dark cycle) and homeostatic sleep drive (adenosine buildup creating sleep pressure throughout the day).
• Self-care is broader than relaxation: it encompasses awareness, self-control, and self-reliance to maintain health across all wellness dimensions—not just spa visits, but also scheduling appointments, managing time, and getting adequate sleep.

💥 Understanding Stress and the Body's Response

💥 What stress is

Stress: "a state of worry or mental tension caused by a difficult situation" (WHO).

• The stressor is the situation or cause of the stress.
• The excerpt explains that a stressor threatens homeostasis, and the stress response is the body's effort to regain balance.
• Stressors vary widely in magnitude:
  • Major: natural disasters, sudden loss of a loved one
  • Minor: running late
• Important point: while stressors differ greatly, the body's response systems are the same.

⚡ The fight-or-flight response

When a stressor is perceived, the body activates the sympathetic nervous system:

Initial trigger:

• Neurotransmitter norepinephrine (noradrenaline) is released
• This is the same system activated during exercise

Endocrine (hormonal) cascade:

• The sympathetic nervous system triggers hormone release:
  • Epinephrine (adrenaline)
  • Norepinephrine (noradrenaline)
  • Cortisol
• These hormones tell the body to continue the reaction until the stressor is gone

Downstream physiological responses:

• Increased heart rate
• Increased blood pressure
• Increased breathing rate
• Airway dilation
• Pupil dilation
• Blood diverted to muscles and away from skin (skin may appear pale)
• Liver converts stored glycogen into glucose for energy

Key insight: These responses occur whether the threat is real or merely perceived.

⏱️ Types of Stress: Duration and Quality

⏱️ Acute vs chronic stress

Type	Duration	Examples	Health impact
Acute stress	Short-term	Vehicle approaching, loud noise, public speaking, upcoming exam	Manageable; we are well-equipped to handle small doses
Chronic stress	Long-term	Tumultuous home/work environment, ongoing medical or financial stress	Serious effects: continuous nervous system activation leads to multiple health problems

Chronic stress consequences:

• Tension headaches
• Inflammation of the circulatory system
• Hypertension, heart attack, stroke
• Impaired immune system function
• Changes in appetite and gastrointestinal function
• Decreased sexual drive
• Fertility issues (both males and females)
• Menstrual dysfunction (females)

😊 Distress vs eustress

Distress: stress resulting from "being overwhelmed by demands, losses, or perceived threats."

Eustress: stress resulting from "challenging but attainable and enjoyable or worthwhile tasks."

How to distinguish:

• Distress leaves you feeling overwhelmed and negative
  • Example: an argument with a friend
• Eustress comes from positive challenges you'll feel good about completing
  • Example: feeling stress before giving a presentation that is a good opportunity

Don't confuse: The presence of stress doesn't automatically mean harm—the quality and context matter.

📚 Allostatic load

Allostatic load: the compilation of chronic stress that builds up over time.

• Explains why someone might react strongly to a seemingly minor stressor
• When life stressors exceed one's ability to cope, allostatic overload may result
• Causes continuous activation of the stress response
• Results in physical "wear and tear" from chronic stress
• Can have negative health impacts

Example: A small change in plans that would normally cause minimal stress triggers a major reaction because of accumulated stress over time.

🛠️ Managing Stress

🛠️ Practical coping strategies

The excerpt emphasizes that everyone will face stressful situations and provides tools to deal with stress:

• Doing physical activity
• Getting enough sleep
• Meditating
• Eating well
• Doing enjoyable activities
• Talking to someone you trust
• Connecting with others (family, friends, community, faith connections)
• Taking breaks from stressors when possible (e.g., don't watch distressing news repeatedly)

Important warning: Avoid using alcohol or drugs to cope—they may provide short-term relief but worsen stress long-term.

When to seek help: If you are struggling to manage stress, reach out to a professional.

😴 Sleep: Regulation and Importance

😴 Why sleep matters

Sleep is often overlooked in lifestyle change discussions (compared to nutrition, physical activity, or quitting smoking/drinking).

Current sleep deficit:

• Roughly 33% of adults don't get enough sleep
• An even greater percentage of adolescents lack adequate sleep

Health consequences of sleep deprivation and sleep disorders:

• Increased risk of: hypertension, diabetes, obesity, depression, heart attack, stroke
• Decreased productivity
• Increased healthcare needs
• Increased chance of injury
• Serious disasters caused by severely sleep-deprived individuals
• In 2021: 682 deaths associated with "drowsy-driving"

🌓 Circadian rhythms

Circadian rhythms: "the physical, mental, and behavioral changes an organism experiences over a 24-hour cycle."

How they work:

• Many factors influence circadian rhythms (eating, physical activity)
• Biggest influence: the light-dark cycle
• Bodies naturally want to wake during light hours and sleep during dark hours
• The hormone melatonin is produced when it's dark, triggering systems to prepare for sleep

Disruptions:

• Overnight shift work
• Staying up very late
• Sleep changes from night shift work can cause loss of connection with the light-dark cycle, altering circadian rhythms
• Artificial light from lamps or tech devices may alter the sleep-wake cycle

💤 Homeostatic sleep drive

Homeostatic sleep drive: sleep pressure that builds up from the time we wake until we go to sleep.

Mechanism:

• Sleep pressure increases the longer we are awake
• Caused by a buildup of adenosine in the brain
• After a good night's sleep, pressure is low and begins increasing again through waking hours

How to maintain strong sleep drive:

• Wake at a consistent time
• Stay awake until ready for bed
• Avoid daytime naps: they decrease sleep pressure and can make it hard to fall asleep at night
• Limit caffeine: it blocks adenosine receptors, altering sleep drive

Don't confuse: Circadian rhythms (external light-dark cycle influence) vs homeostatic sleep drive (internal adenosine buildup)—both work together to regulate sleep.

🧘 Self-Care: A Holistic Approach

🧘 What self-care really means

Self-care: "the ability to care for oneself through awareness, self-control, and self-reliance in order to achieve, maintain, or promote optimal health and well-being."

Why the definition is broad:

• The exact explanation is unclear because of "difficulty integrating the diverse definitions developed over time across disciplines"
• The above definition synthesizes 31 different articles

Core essence: Taking care of yourself.

🌈 Beyond relaxation and luxury

Common misconception: Self-care is only spa visits or lavish trips.

Reality—self-care is not always relaxing, fun, or extravagant:

• Scheduling necessary appointments
• Going for a walk to reduce stress
• Completing tasks that have been weighing on your mind
• Learning time management skills
• Getting enough sleep

Connection to wellness dimensions: The definition incorporates "well-being," so working toward improvement in any wellness area counts as self-care:

• Emotional wellness
• Physical wellness
• Vocational (occupational) wellness
• Social wellness
• Spiritual wellness
• Intellectual wellness
• Environmental wellness
• Financial wellness

Example: Improving financial wellness by creating a budget is self-care, even though it's not traditionally "relaxing."