Exercise Physiology Lecture Notes Review

Flashcards covering key concepts from exercise physiology lecture notes, including acute responses, chronic adaptations, energy systems, muscular system, cardiovascular system, respiratory system, thermoregulation, and nutritional considerations.

What are acute responses to exercise?

Immediate physiological changes that occur during a single bout of exercise.

What are chronic adaptations to training?

Long-term physiological changes that occur due to regular exercise over time.

What is homeostasis and why is it important during exercise?

The body's ability to maintain a stable internal environment despite external changes.

Which body systems must work together seamlessly during physical activity?

The muscular, cardiovascular, respiratory, and nervous systems.

What is the phosphagen system (ATP-PCr system)?

Provides immediate energy for high-intensity activities lasting up to 10 seconds.

What is aerobic metabolism and how does it work?

Provides energy for longer-duration activities lasting over two minutes, requiring oxygen to produce ATP.

How can training enhance the phosphagen system?

Sprint training can increase stored ATP and phosphocreatine levels in muscles.

How can training enhance anaerobic glycolysis?

High-intensity interval training (HIIT) can improve lactate threshold.

How can training enhance aerobic metabolism?

Endurance training increases mitochondrial density in muscle cells.

What are the three types of muscles, and which is the focus in exercise physiology?

Skeletal, cardiac, and smooth muscles; exercise physiology primarily focuses on skeletal muscles.

What are the characteristics of slow-twitch muscle fibers (Type I)?

Rich in mitochondria and myoglobin, highly efficient at using oxygen, and have high resistance to fatigue.

What are the characteristics of fast-twitch muscle fibers (Type II)?

Can be further divided into Type IIa (fast oxidative) and Type IIb (fast glycolytic); primarily rely on anaerobic metabolism for quick bursts of energy.

How does muscle contraction begin at the neuromuscular junction?

A motor neuron sends an electrical impulse to the neuromuscular junction, releasing acetylcholine (ACh).

What is the role of an action potential in muscle contraction?

Electrical impulse that triggers the release of calcium ions from the sarcoplasmic reticulum.

How does calcium facilitate cross-bridge cycling in muscle contraction?

Calcium binds to troponin, causing tropomyosin to move away from actin binding sites, allowing myosin heads to form cross-bridges and pull actin filaments.

How are motor units recruited during exercise?

Motor units are recruited based on the force required; smaller units are activated first for low-intensity activities, while larger units are recruited as intensity increases.

How does strength training affect muscle characteristics?

Resistance training stimulates fast-twitch fibers, leading to muscle size increase (hypertrophy) and greater force production.

How does endurance training affect muscle characteristics?

Endurance training enhances aerobic capacity by improving slow-twitch fiber efficiency, increasing mitochondrial density, and improving oxygen delivery.

How does heart rate respond to exercise?

Increases significantly during exercise; rises to over 150 beats per minute during vigorous activity like sprinting.

What is stroke volume, and how does it change during exercise?

Refers to the amount of blood pumped by the heart with each beat; increases due to enhanced venous return and increased contractility.

What is cardiac output, and how does it respond to exercise?

Calculated as heart rate multiplied by stroke volume (CO = HR × SV); can increase up to 20 liters per minute in elite athletes during intense exercise.

What are the long-term cardiovascular adaptations from regular aerobic training related to heart size?

The left ventricle becomes larger and stronger, allowing for greater stroke volume.

What are the long-term cardiovascular adaptations from regular aerobic training related to resting heart rate?

Trained individuals often have lower resting heart rates due to improved efficiency in their cardiovascular systems.

What are the long-term cardiovascular adaptations from regular aerobic training related to capillary density?

Regular training increases capillary networks in muscle tissues, improving oxygen delivery at a cellular level.

What is the role of the nasal cavity in the respiratory system?

Filters, warms, and humidifies incoming air.

What is the function of the bronchi and bronchioles?

Branching airways that lead to the alveoli where gas exchange occurs.

How does breathing rate change during exercise?

As exercise intensity rises, so does the breathing rate (e.g., increasing from 12-20 breaths per minute at rest to 35-45 breaths per minute during vigorous activity).

What is tidal volume, and how does it change during exercise?

Tidal volume refers to the amount of air inhaled or exhaled with each breath; it increases to allow for greater air exchange (e.g., increasing from 500 mL at rest to 2-3 liters during intense exercise).

How does oxygen uptake (VO2) change during exercise?

The amount of oxygen consumed by the body during physical activity increases as exercise intensity rises.

How does carbon dioxide production (VCO2) change during exercise?

muscles work harder, they produce more carbon dioxide as a byproduct of metabolism, which the respiratory system must efficiently eliminate.

What are the long-term adaptations to the respiratory system related to lung capacity?

Training can lead to improved lung volumes and capacities, allowing for greater oxygen intake during exercise.

What are the long-term adaptations to the respiratory system related to alveolar efficiency?

Regular training improves gas exchange efficiency at the alveolar level, increasing oxygen saturation in blood.

What are the primary mechanisms of heat loss during exercise?

Evaporation (sweating), conduction, and convection.

Name Physiological Responses to Heat Stress

Increased Heart Rate, Sweating Response and Maintaining Hydration.

Name Physiological Responses to Cold Exposure

Shivering and Vasoconstriction.

Name Macronutrients that provide the energy required for physical activity

Carbohydrates, Proteins, and Fats.

Why is Hydration vital for exercise?

Water regulates body temperature, transports nutrients, and removes waste products.

Example Micronutrient benefits for Athletes

Iron is crucial for oxygen transport in the blood; athletes with low iron levels may experience fatigue and decreased performance.

Why is Meal Timing important relative to physical activity?

Consuming a balanced meal or snack containing carbohydrates and protein about 1-3 hours before exercise can enhance performance, and Eating a meal rich in carbohydrates and protein within 30 minutes after exercise can help replenish glycogen stores and promote muscle recovery.