Foundations of Health and Human Performance

Endocrine System

System of glands that secretes hormones to regulate body function; exercise both affects and is affected by hormones

Nervous system

Communication network of the body; exercise influences sympathetic and parasympathetic activity.

Cardiorespiratory system:

Combined cardiovascular and respiratory systems that transport oxygen and remove carbon dioxide

Cardiovascular system

Heart, blood, and blood vessels; transports oxygen and nutrients.

Respiratory system:

Lungs and airways; brings in oxygen and removes carbon dioxide.

Musculoskeletal system

Bones, muscles, joints, tendons, ligaments, cartilage, and connective tissue that support, protect, and move the body.

Type I fibers:

Slow-twitch fibers; produce tension slowly, resist fatigue, and rely more on aerobic metabolism

Type II fibers:

Fast-twitch fibers; produce force quickly, fatigue faster, and rely more on anaerobic metabolism

Muscular endurance

Ability to perform repeated contractions against a submaximal resistance.

Muscular strength

Maximum force a muscle or muscle group can exert in one effort with proper form.

Muscular power

Ability to produce high force quickly; greatest force in the shortest time

Muscular hypertrophy

Enlargement of skeletal muscle fibers, usually from resistance training.

Hyperplasia

Increase in number of muscle fibers; controversial and unlikely in humans

Atrophy

Decrease in muscle mass.

Agility

Ability to stop, start, and rapidly change direction in response to a stimulus.

Speed

Distance covered per unit time.

Flexibility

Range of motion around a joint.

Balance

Ability to maintain static or dynamic equilibrium.

Stability

Ability to return to a desired position after a disturbance.

Anthropometrics

Measurement of the human body, such as height, weight, and girths

BMI

Body mass index; weight relative to height.

Body composition:

Relative proportions of fat mass and lean tissue, often discussed as body fat percentage

Aerobic exercise

Exercise that requires oxygen for metabolism.

Anaerobic exercise

Exercise that does not rely primarily on oxygen availability during performance.

VO2max

Highest rate of oxygen transport and use at maximal effort; measured in mL/kg/min

Anaerobic threshold

Point where normal oxygen intake can no longer meet demand and fatigue rises quickly.

ATP-PC system

Anaerobic energy system for very high-intensity efforts lasting about 10- 15 seconds.

Glycolytic system

Anaerobic energy system supporting moderate-to-high intensity work up to about 3 minutes.

Oxidative system

Aerobic system used for long-duration energy production.

1RM

Maximum amount of weight that can be lifted once with proper form.

Resting heart rate

Heart rate at rest, measured in beats per minute.

Heart rate reserve:

Difference between max heart rate and resting heart rate.

Blood pressure

Force of blood against vessel walls; recorded as systolic/diastolic.

HDL

High-density lipoprotein; “good” cholesterol.

LDL

Low-density lipoprotein; “bad” cholesterol.

Energy expenditure

Total energy cost of maintaining life and performing activity.

Resistance training

Working against resistive loads to improve health, fitness, and performance.

Early adaptations of Resistance Training

First 6-12 weeks are dominated mainly by neural changes

Later adaptations with Resistance Training

With longer training, hypertrophy and structural changes contribute more to strength and power gains

Motor unit

A motor neuron and all the muscle fibers it innervates

Motor unit recruitment

Activating more motor units to produce more force

Rate coding

Increasing motor neuron firing rate to increase force

Synchronization

Motor units firing more together; may improve force production.

Size principle

Smaller motor units are recruited first; larger units are added as force demands rise.

Key takeaway

Strength gains early in training come from better recruitment, firing rate, coordination, and neural efficiency.

Hypertrophy:

Increase in muscle fiber cross-sectional area from larger actin and myosin content

Fiber-type shift

Resistance training may shift Type IIx fibers toward Type IIa, making them slightly more oxidative and fatigue resistant.

Type II response

Type II fibers generally hypertrophy more than Type I fibers

Bone mineral density:

Resistance training can increase BMD because heavier muscular forces place more stress on bone

Best bone-loading lifts

Multi-joint lifts that load the spine or hip directly or indirectly, such as squats, deadlifts, cleans, snatches, jerks, and presses

Metabolic emphasis

Resistance training mainly stresses phosphagen and glycolytic pathways.

Cardiovascular effect

: Usually does not raise VO2max as much as aerobic training, but can improve running economy and local muscular endurance

Body composition

Hypertrophy increases fat-free mass and can reduce body fat percentage, especially when training volume raises caloric expenditure

Motor performance:

Can improve sprinting, jumping, throwing, kicking, and running economy when training is sport-specific.

Specificity

The body adapts specifically to the way it is trained.

Sex

Relative strength differences are mostly tied to body size and hormone profile; muscle tissue itself can adapt similarly.

Age

Aging is linked to sarcopenia and lower fast-twitch fiber capacity

Genetics

: Fiber-type makeup helps determine hypertrophy and performance ceiling

Cardiac output

Amount of blood pumped per minute; stroke volume times heart rate

Stroke volume

Blood ejected with each heartbeat; rises until moderate intensity, then usually plateaus.

Heart rate

Increases roughly linearly with exercise intensity

Oxygen uptake (VO2):

Amount of oxygen consumed by tissues; rises with active muscle mass and intensity

Systolic blood pressure

Typically increases during aerobic exercise

Diastolic blood pressure

Usually stays the same or decreases slightly during exercise

Vasodilation:

Widening of vessels to increase blood flow to active tissue.

Minute ventilation

Volume of air breathed each minute; rises because respiratory rate and tidal volume increase

Cardiovascular

Higher maximal cardiac output, higher stroke volume, lower resting and submax heart rate, higher VO2max, and greater capillary density.

Respiratory

Usually moderate changes; at submax workloads tidal volume increases and breathing frequency may decrease

Muscular aerobic capacity

Greater ability to exercise at a higher percentage of VO2max with more glycogen sparing and better fat use

Cellular changes

More and larger mitochondria, more myoglobin, and improved oxygen extraction and ATP production

Fiber changes

Type I fibers improve most; Type IIx may gradually shift toward Type IIa

Bone and connective tissue

Weight-bearing aerobic work can increase bone mass if intensity is high enough.

Body composition

Usually lowers body fat percentage, with little effect on fat-free mass

Altitude with aerobic adaptation

Can change oxygen availability and training response

Smoking with aerobic adaptation

Reduces respiratory and cardiovascular efficiency

Blood Doping

Artificially boosts oxygen-carrying capacity but is banned and unethical.

Genetic ceiling

Each person has an upper limit to aerobic capacity.

Age and sex

Older adults and females generally have lower relative aerobic capacity than younger males.

Job expectations in Personal Training

Recruit clients, build relationships, assess needs, design programs, and guide implementation safely

Client recruitment in Personal Training

Results, consistency, referrals, and social proof matter more than excessive promotion

Mavens in Personal Training

Trusted professionals such as doctors, baristas, or real-estate agents who can refer clients

Needs analysis

First listen to what the client wants and needs before prescribing exercise.

Stages of change

Precontemplation, contemplation, preparation, action, and maintenance

SMART objectives in Personal Training

Specific, measurable, action-oriented, realistic, and timed

Process goal

Focuses on behavior or technique.

Performance goal

Focuses on personal improvement or a measurable performance outcome

Outcome goal:

Focuses on final result, often with social comparison.

Waiver

A signed waiver is essential when money changes hands, though it is not complete protection

Establish rapport

Be welcoming, responsive, and credible without being boastful

Do not over-coach

Give 1-2 cues at a time and teach basics before advanced details

Sequential coaching

Start with simple fundamentals, reinforce success, then add new details gradually

Patience

Technique learning takes time; calm correction works better than overload

Oreo critique

Positive comment, constructive correction, positive comment.

Group fitness instructor

Leads intentionally designed exercise classes for multiple participants

Difference from personal training:

Less individual assessment, less individualized programming, and more broad verbal cueing

PAR-Q

Preparticipation screening form used to flag medical concerns before exercise

Class design

Match class purpose, participant ability, equipment, room setup, music, time, and temperature

FITT in group fitness

Frequency, intensity, time, and type can guide class structure

Order of exercises

Usually large to small muscle groups, with cardio and recovery placed intentionally

Modifications

Every class should include easier and harder versions by changing load, range of motion, tempo, or exercise choice