Novel methods of acutely improving an individual’s athletic performance are regularly utilised in an effort to gain unique advantages in competitive contexts. One such method is post-activation potentiation (PAP). Eccentric resistance exercise has been demonstrated to have unique properties to that of traditional resistance methods. Few studies have investigated the effects eccentric resistance exercise may have on potentiating physiological characteristics such as force, speed, and power. This thesis aims to: (1) review and synthesise existing literature regarding physiological and neuromuscular underpinnings of PAP and eccentric exercise (Chapter One); (2) examine test-retest reliability of the test conditions used to measure physiological aspects pertinent to athletic populations (Chapter Two); and (3), investigate the acute effects isokinetic eccentric resistance exercise has on expressions of force, speed, and power (Chapter Three). Chapter Four discusses and summarises key findings of the studies undertaken, outlining strengths and limitations, and provides recommendations for future research. As part of the literature review in Chapter One, research regarding the pertinent variables of PAP and eccentric exercise was examined. While there is a consensus that PAP can occur and that eccentric exercise can have superior adaptive qualities to traditional exercise methods, it is evident there is little quantification for what training volumes, recovery periods, and individual characteristics are most conducive to the application of eccentric exercise to elicit PAP. Chapter Two examined the inter-day reliability of the drop-jump, loaded counter-movement jump, and six-second peak power test metrics using equipment from OptoJumpᵀᴹ, Kinetic Performance Technology, and Wattbike Ltd. The experimental set-up and metrics were found to be reliable (<10% CV) for measuring flight time, relative power, and jump height in the drop jump; jump height and peak velocity for the lighter loaded counter-movement jump (25 kg); jump height, peak power, peak force, peak velocity and peak relative power for the heavier loaded counter-movement jump (45 kg); and peak power, relative power, peak cadence and cadence at which peak power occurred in the six-second peak power test. In Chapter Three, 19 resistance trained males completed three sessions of drop jumps, loaded counter-movement jumps, and six-second peak power cycling tests pre- and post-interventions using an isokinetic eccentric ergometer to induce PAP or a concentric cycling control. Measures of relative power in heavier loaded counter-movement jumps were found to be significantly improved (0.02) with moderate effect sizes found in time to peak power (0.80) and cadence at which peak power occurred (0.92) in the six-second peak power cycling test. Results from this research demonstrate a need for higher quality methodological studies to be undertaken examining variables involved in novel training methods such as PAP and eccentric resistance training including volume, intensity, recovery times, and individual characteristics required for beneficial adaptations in this population.