Topic overview

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During exercise, heart rate and stroke volume rise, increasing cardiac output, while blood flow shifts toward active skeletal muscle. Oxygen consumption and ventilation increase; VO₂ max reflects aerobic fitness, and the ventilatory threshold marks a change in the breathing response. Multiple energy systems contribute, with fuel use varying by exercise intensity. After activity, excess post-exercise oxygen consumption supports recovery processes. The lesson also distinguishes slow and fast muscle fibers and compares adaptations to aerobic and resistance training. Further topics include acute hormonal responses, temperature regulation and fluid balance, exercise at altitude, and additional considerations such as cardiac morphology, overtraining, aging, and female physiology.