Exercise Physiology Flashcards
(10 cards)
What is the role of ATP in muscle contraction?
ATP provides energy for the myosin head to attach to actin, perform the power-stroke, and release the cross-bridge for continued muscle contraction.
What are the three methods of ATP synthesis?
Phosphocreatine system (anaerobic), Anaerobic glycolysis, and Aerobic oxidative phosphorylation.
When is the phosphocreatine system primarily used?
During the initial 2–10 seconds of high-intensity exercise for quick and powerful energy.
What is the primary energy system used during sustained, moderate activity?
Aerobic ATP synthesis through oxidative phosphorylation.
Define oxygen delivery (DO2) in the context of exercise physiology.
Oxygen delivery is the amount of oxygen transported to tissues, calculated as Cardiac Output × Arterial Oxygen Content.
What factors influence oxygen uptake (VO2)?
Muscle blood flow, capillary and mitochondrial density, Hb-O2 affinity, muscle mass, fibre type, and nutrient availability.
What changes occur in respiratory function during exercise?
Minute ventilation increases significantly, depth of breath increases before rate, and respiratory muscle VO2 usage increases.
How does cardiac output respond to exercise?
It increases up to 5 times, with heart rate increasing linearly and stroke volume increasing then plateauing.
How does peripheral circulation adapt during exercise?
Blood is redirected to muscles, skin blood flow increases, and arterioles vasodilate to enhance blood flow.
What are long-term adaptations to endurance training?
Increased capillary and mitochondrial density, improved enzyme activity, and enhanced oxygen utilisation.
