Exercise at higher intensities and longer durations have the most robust evidence supporting their role in EIH. This is true of both long-duration aerobic training as well as high-intensity anaerobic training. This type of activity, however, may not be the most practical type of activity prescribed in a clinical population, especially in people with painful conditions, due to decreased conditioning and tolerance. Beyond long-duration and/or high-intensity aerobic exercise, there is growing evidence supporting the use of other forms and intensities of exercise that may induce EIH. Alternative forms of exercise, such as isometric stabilization, have been shown to decrease pain in a population of patients with low back pain. Koltyn and Arbogast investigated acute effects of exercise on pain perception and found that a single bout of resistance exercise at 75% of maximum intensity produces significant increases in pain thresholds and reductions in pain ratings.11 EIH can also occur during and following short duration (e.g., 1.5-5 min) and lower intensity (e.g., 15-50% max) isometric exercise. Along with high-intensity training, long-duration/low-intensity isometric contractions also have been found to produce an analgesic response. Studies have suggested different post-exercise pain responses in chronic pain populations compared to healthy controls, however questions still remain over the influence of various exercise intensities, protocols or types of contractions. Slater, et al examined the effects of eccentric exercise versus combined concentric-eccentric exercise at an intensity of 30% of max voluntary contraction (MVC) showed a significant increase in pain thresholds for both exercise protocols. Their study highlighted the need for further research to examine if changes also occur in response to single exercise modes. To date, no studies have compared EIH produced by isometric and concentric exercises at similar intensities and duration. Furthermore, little research in EIH has compared various forms of exercise to non-exercising controls.