Unit 3: Exercise physiology Flashcards
(25 cards)
What is the difference between a response and an adaptation to physical activity?
Response: Acute, temporary change during physical activity. Adaptation: Chronic, structural or functional change due to repeated exposure to exercise.
How does physical activity challenge homeostasis?
It increases demands on all body systems, requiring them to adjust functionally to maintain internal balance.
What are the major types of muscle contractions?
- Isometric: Static, no length change.
- Concentric: Muscle shortens.
- Eccentric: Muscle lengthens under tension.
- Isotonic: Constant load, changing muscle length.
- Isokinetic: Constant speed contractions.
Define strength and its main categories.
Strength = Neuromuscular ability to resist or produce force.
Categories: * Maximum strength * Speed strength * Explosive strength * Endurance strength
Why do eccentric contractions produce more force but carry greater risk?
They allow higher force generation but cause greater tissue stress, leading to more damage.
How does the endocrine system respond to exercise?
- ↑ Adrenaline: ↑ HR, ventilation, cardiac output.
- ↑ Cortisol: Mobilizes energy.
- ↓ Insulin: Enhances muscle glucose uptake.
- ↑ Glucagon: Promotes liver glycogenolysis.
- ↑ Testosterone: Promotes protein synthesis.
What are myokines and exerkines?
- Myokines: Cytokines released by contracting skeletal muscle.
- Exerkines: Signaling molecules from multiple tissues during exercise.
What are the respiratory responses to exercise?
- ↑ Ventilation rate & depth.
- Mechanisms: Anticipatory neural input, sympathetic activation, chemoreceptor feedback.
How does cardiac output (Q) increase during exercise?
Q = HR × SV; ↑ HR via sympathetic stimulation + Bainbridge reflex; ↑ SV via stronger myocardial contraction.
What is the role of functional sympatholysis in exercise?
It allows localized vasodilation and increased blood flow in active muscles.
What is VO₂ and how is it calculated?
VO₂ = Q × (a-v O₂ difference); Represents O₂ consumption.
What is exercise-induced hypoalgesia (EIH)?
Temporary reduction in pain sensitivity after exercise, involving endogenous opioid and non-opioid pathways.
Explain DOMS and its causes.
Delayed Onset Muscle Soreness: Pain post-exercise caused by eccentric contractions leading to microtrauma.
What are the neural adaptations to resistance training?
- ↑ Motor unit recruitment.
- ↑ Firing rate.
- Better coordination.
What causes muscle hypertrophy?
↑ Protein synthesis in muscle fibers triggered by mechanical load + hormones.
What is the significance of the testosterone/cortisol (T/C) ratio?
Marker of training status; high ratio indicates anabolic state.
Describe sympathetic and parasympathetic overtraining syndromes (OTS).
- Sympathetic OTS: ↑ Resting HR, insomnia.
- Parasympathetic OTS: Fatigue, depression.
How do the respiratory muscles adapt to training?
- ↑ Strength and endurance.
- ↑ Capillary density.
- Better ventilatory efficiency.
How does the heart adapt to exercise?
- Resting HR ↓ due to ↑ parasympathetic tone.
- SV ↑ due to stronger contractions.
What vascular changes occur with training?
- Angiogenesis: More capillaries.
- ↑ Vessel diameter.
What is 1RM and how is it used in strength training?
1 Repetition Maximum: Maximum weight lifted once; used to prescribe intensity for training goals.
How should strength training be adapted for older adults?
Adjust intensity carefully; focus on preventing sarcopenia.
What is VO₂max and why is it important in endurance training?
Maximum oxygen uptake during intense exercise; reflects aerobic fitness.
What is the difference between VO₂max and VO₂peak?
VO₂max: Max O₂ consumption at maximal effort; VO₂peak: Max O₂ consumed during a specific test.
