The Effect of Caffeine Ingestion on Delayed Onset Muscle Soreness.Hurley, Caitlin F.; Hatfield, Disa L.; Riebe, DeborahJournal of Strength & Conditioning Research: Post Acceptance: September 3, 2013 doi: 10.1097/JSC.0000000000000220 Original Investigation: PDF Only Abstract Abstract The beneficial effects of caffeine on aerobic activity and resistance training performance are well documented. However, less is known concerning caffeine's potential role in reducing perception of pain and soreness during exercise. In addition, there is no information regarding the effects of caffeine on delayed onset muscle soreness. The primary purpose of this study was to examine the effect of caffeine ingestion on muscle soreness, blood enzyme activity, and performance following a bout of elbow flexion/extension exercise. Nine low caffeine consuming males (body mass: 76.68 +/- 8.13kg; height: 179.18 +/- 9.35cm; age: 20 +/- 1 yr) were randomly assigned to ingest either caffeine or placebo one hour prior to completing 4 sets of 10 bicep curls on a preacher bench, followed by a fifth set in which subjects completed as many repetitions as possible. Soreness and soreness on palpation intensity was measured using three, 0-10 visual analog scales prior to exercise, and 24, 48, 72, 96 and 120 hours post exercise. Following a washout period, subjects crossed-over to the other treatment group. Caffeine ingestion resulted in significantly (p <=0.05) lower levels of soreness on day 2 and day 3 compared to placebo. Total repetitions in the final set of exercise increased with caffeine ingestion compared to placebo. This study demonstrates that caffeine ingestion immediately before an upper-body resistance training out enhances performance. A further beneficial effect of sustained caffeine ingestion in the days following the exercise bout is an attenuation of delayed onset muscle soreness (DOMS ). This decreased perception of soreness in the days following a strenuous resistance training workout may allow individuals to increase the number of training sessions in a given time period. Copyright (C) 2017 by the National Strength & Conditioning Association.