Untitled Flashcards Set

What is health according to the World Health Organization (WHO)?

Health is a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity.

What are chronic diseases and why are they important?

Chronic diseases persist over a long duration and are the leading public health burden worldwide, accounting for approximately 60% of deaths globally each year.

What do the leading causes of death in the U.S. include today?

Current leading causes of death include cardiovascular disease (40%), cancer (23%), stroke (6%), and diabetes (3%).

What are the 5 health-related components of fitness?

Cardiovascular endurance, muscular strength, muscular endurance, flexibility, and body composition.

What are the ACSM recommended physical activity guidelines?

150 minutes of moderate-intensity aerobic activity OR 75 minutes of vigorous-intensity aerobic activity per week, plus muscle-strengthening activities on 2 days.

Why are not all obese individuals the same?

Some obese individuals are metabolically healthy while others are not; active obese individuals have a lower risk of mortality compared to sedentary normal-weight individuals.

Define physical activity and exercise.

Physical Activity: Any bodily movement produced by skeletal muscles that results in substantial increase in energy expenditure. Exercise: A structured and planned subset of physical activity aimed at improving fitness.

How can heart rate estimate energy expenditure and exercise intensity?

Heart rate correlates with energy expenditure and can be measured using % of VO2 Max, % of Heart Rate Max (HRmax), and Metabolic Equivalents (METs).

What defines light, moderate, and vigorous intensity exercise?

Light Intensity:

What percentage of Americans do not meet physical activity recommendations?

75% of Americans do not meet physical activity recommendations; 25% engage in no physical activity at all.

What are the different types of muscles?

Skeletal (voluntary), cardiac (involuntary), and smooth (involuntary).

What are the basic structural components of muscle?

Muscle → Muscle Fiber → Myofibril → Sarcomere (the functional unit).

What are the characteristics of muscle fiber types?

Type I: High endurance, fatigue-resistant; Type IIa: Moderate endurance, more forceful contractions; Type IIx: Powerful but fatigues quickly.

What is a motor unit?

A motor unit consists of a motor neuron and all muscle fibers it innervates.

What is an action potential?

A brief electrical signal that travels down a neuron, leading to muscle contraction.

What occurs in the cross-bridge cycle?

Myosin binds to actin, the power stroke occurs, cross-bridge detachment happens when ATP binds myosin, and ATP hydrolysis resets myosin.

What does the size principle of motor unit recruitment refer to?

Small motor units are recruited first, followed by larger units as more force is needed, allowing for fine motor control.

What is the significance of myostatin?

Myostatin is a protein that partially blocks the function of satellite cells; blocking it can enhance muscle growth.

What does muscular fitness include?

Muscular fitness encompasses both muscular strength and muscular endurance.

What factors determine strength?

Strength is determined by muscle size and the ability of the nervous system to recruit motor units.

How do strength gains differ between men, women, old, and young individuals?

Strength gains are generally similar across genders and ages, but often relate to initial strength levels and genetic potential.

What physiological adaptations occur following resistance training?

Neural adaptations, muscle hypertrophy, and improvements in bone and connective tissue.

What are the major components of the cardiac cycle?

The cardiac cycle includes the events of systole (contraction) and diastole (relaxation).

Describe the components of the cardiac conduction system.

The Sinoatrial (SA) node, Atrioventricular (AV) node, and Purkinje fibers are key components, transmitting electrical impulses for heart contractions.

How is heart rate regulated at rest and during exercise?

Parasympathetic innervation slows HR; sympathetic innervation increases HR in proportion to exercise intensity.

What happens to blood flow during exercise?

Blood is redistributed to active muscles while reducing flow to non-essential organs.

How is oxygen transported in blood?

98% of oxygen is bound to hemoglobin and 2% is dissolved in plasma.

What is VO2 max?

VO2 max is the maximal capacity to transport and utilize oxygen, influenced by age, sex, training, and genetics.

What is the significance of the FITT principle in exercise prescription?

FITT stands for Frequency, Intensity, Time, and Type, essential for designing effective exercise programs.

What are the two common types of field tests for assessing muscular fitness?

Push-Up Test for upper body muscular endurance and Curl-Up Test for abdominal muscular endurance.

What do the terms essential and non-essential fat refer to?

Essential fat is necessary for body functions; non-essential fat serves as storage.

What distinguishes direct from indirect body composition measures?

Direct measures involve dissection (impractical), while indirect methods include skinfolds, DXA, and BIA.

How is body fat percentage calculated using the Siri Equation?

%BF = (495 / Body Density) - 450.