The Effect of Pomegranate Juice Supplementation on Strength and Soreness After Eccentric Exercise Trombold JR, Reinfeld AS, Casler JR, and Coyle EF. J Strength Cond Res. 2011 July; 25(7): 1782-1788. https://www.ncbi.nlm.nih.gov/pubmed/21659887 Both strength reduction and delayed-onset muscle soreness is common following eccentric exercise especially between 24-48 hours postexercise. Attenuation of this weakness and muscle soreness, through dietary supplements (NSAIDS, vitamin E, etc) has been studied, yet an optimal treatment has yet to be identified. Therefore, Trombold and colleagues completed a study to determine if supplementation with pomegranate juice improved recovery of skeletal muscle strength, and decreased muscle soreness, after eccentric exercise in subject who routinely performed resistance training. Seventeen resistance trained male subjects were included in a double-blind, counterbalanced, placebo-controlled crossover experiment receiving either pomegranate juice (PJ) or placebo (PLA). The subjects were instructed to “maintain their normal diet and current level of physical activity, refrain from consumption of anti-inflammatory or antioxidant supplements.” Each subject ingested 125 ml of either, PJ or PLA, twice daily while continuing their normal weight training routine from days 1 through 6. On day 7, each subject performed a 1 repetition maximum isometric elbow flexion and knee extension. On day 8, each subject performed 3 sets of 20 unilateral eccentric elbow flexion exercises, using a Biodex isokinetic dynamometer, and 6 sets of 10 unilateral eccentric knee extension exercises using a Cybex leg extension machine and load cell. A higher number of sets were used to fatigue the knee extensor muscles due to increased fatigue capacity because of its ambulatory nature. Immediately after exercise, all subjects consumed of an additional bottle (250 ml) of PJ or PLA. Measurements of subjective muscle soreness, through the use of a visual analog scale, and isometric strength were examined. These results were recorded immediately before exercise and 2 hours, 24 hours, 48 hours, 72 hours, 96 hours and 168 hours postexercise. The authors reported that during the 2 to 168 hour postexercise period the PJ group showed significant reduction in elbow flexion muscle soreness (p = 0.006) and elevated elbow strength (p = 0.031) compared to the PLA group. However, strength and soreness scores for the knee extensor muscles were not significantly different. Overall, this study illustrates an ergogenic effect of pomegranate juice supplemntation to attenuate elbow flexor muscles in resistance-trained individuals following eccentric exercise. The authors attribute this to high levels of polyphenols found in pomegranate juice, as the results are in agreement with other polyphenol supplementation studies. These compounds are thought to stabilize cell membranes, as well as, promote an anti-inflammatory process. This study is limited, however, by the fact that only a significant difference was found in the elbow flexion muscles and not the knee extensors. Perhaps this can be attributed to the size difference in the two muscle groups. With both muscle groups being tested on the same subject it may be that the PJ had a greater impact on the elbow flexors due to their smaller size compared to the knee extensor muscle group. Clearly, more research needs to be completed to fully understand why the knee extensors did not respond to the level of the elbow flexors, and furthermore, if this phenomenon holds true to the rest of the body. If further research demonstrates significant results in other muscle groups, this supplementation could become an excellent tool for clinicians to use to reduce the effects of muscle soreness and weakness following intense bouts of eccentric training. Is this something that you have heard of or currently recommend to your athletes? If so, how you seen a positive effect? If not, how do you advise your athletes in attenuating these postexercise detriments? Written by: Kyle Harris Reviewed by: Stephen Thomas