Heavy resistance exercise is known to elicit acute physiologic responses. These acute responses can either increase (post-activation potentiation [PAP]) or decrease (fatigue) performance. There is limited investigation on the effects of PAP and fatigue during performance of exercise sessions involving multi-joint tasks. The research in this dissertation investigated the acute physiologic responses during high-power resistance exercise, the associated changes in performance and the effects on inter-segmental coordination. In men, performance increases following the onset of exercise, followed by a decrease as additional exercise is performed. In women, performance does not increase significantly, however decreases when additional volume is performed. PAP and fatigue responses were greater in men than women. This gender difference may be associated with ability to recruit higher threshold motor units. PAP was associated with regulatory light chain phosphorylation and a rightward shift in the EMG frequency spectrum. Fatigue was associated with a leftward shift in the EMG frequency spectrum. This is the first study investigating the physiologic mechanisms of PAP and fatigue during multi-joint exercise. The effects of PAP and fatigue on inter-segmental coordination was dependent on relative intensity. This corroborates previous research, and indicates that coordinative structure of multi-joint exercise changes as a function of relative intensity and contractile history. This research has implications on the design of resistance exercise programs. The differences between men and women suggest that exercise programs should be gender specific. Men should maximize performance by manipulating external resistance to account for PAP and fatigue, whereas women are capable of performing a higher volume of exercise. Additionally, women should perform exercise that requires recruitment of higher threshold motor units. The changes in coordinative structure with PAP suggest that transfer of training to performance of other tasks may be optimized when the appropriate relative intensity is selected. Conversely, fatigue negatively affects coordinative structure, which may lead to injury