Anatomy, Physiology and Exercise Physiology
Anatomy, physiology and exercise physiology tests how the body is built and how it responds to exercise: bones, joints, muscles, the heart, lungs, blood, energy systems and thermoregulation. You must link structure to function and acute responses to chronic adaptations.
Core rules
- Skeletal system: 206 bones in the adult; axial skeleton protects organs, appendicular skeleton enables movement. Joint type determines range: hinge (elbow), ball-and-socket (hip), pivot (atlas–axis).
- Muscular system: agonist produces movement, antagonist opposes, synergist stabilises, fixator fixes origin. Muscle contraction follows all-or-none for a motor unit; gradation comes from recruitment and frequency.
- Cardiorespiratory: cardiac output = heart rate × stroke volume. During exercise, HR, SV and a–vO2 difference rise; ventilation rises mainly through rate and depth.
- Energy: ATP–PC is immediate (≈10 s), glycolysis short-term (≈2 min), oxidative long-term. Fat use rises as intensity falls and duration rises.
Worked example
At rest: HR 60 bpm, SV 70 mL → Q = 4.2 L/min. During running: HR 150, SV 110 mL → Q = 16.5 L/min. Reasoning: Q rises because both HR and SV increase; SV plateaus near maximal intensity, so further rises depend mainly on HR. Oxygen uptake also depends on a–vO2 difference.
Traps
- Confusing ventilation (air movement) with respiration (gas exchange).
- Saying lactate causes fatigue; H+ accumulation and other factors contribute.
- Mixing acute responses with chronic adaptations (e.g., bradycardia at rest is chronic).
- Reversing systolic and diastolic pressure.