The effect of exercise induced muscle damage (EIMD) on outdoor running performance

Abstract

This study examined the effect of exercise-induced muscle damage (EIMD) elicited by a bout of plyometrics on outdoor running performance. Seventeen males (mean ± SD: age 37 ± 8 years, height 180 ± 5.3 cm, body mass 75.4 ± 7.5 kg) were recruited from running and triathlon clubs within Cheshire. They were randomly assigned to the treatment (n = 8) or control group (n = 9) with the study adopting a randomized, controlled, repeated measures design. Before and 48 hours after treatment the subjects underwent testing on EIMD markers (muscle thigh circumference, muscle function and muscle soreness) and ran a 5 km outdoor time-trial. During the time-trial speed, heart rate and RPE were measured at each kilometre along with blood lactate at the finish. On completion of the 5 km run the treatment group completed a bout of 10 x 10 drop jumps from a 35 cm bench to elicit EIMD. Multiple independent t-tests along with multiple two-way and three-way ANOVAs were used for analysis. Muscle soreness significantly increased within the treatment group after EIMD (p<0.05), however no significant change occurred in muscle circumference and force production (p>0.05). During the time-trial RPE, heart rate, average running speed and blood lactate did not significantly change in the treatment group (p>0.05). Although average running speed did not significantly change, a decrease was observed with a significantly slower time-trial completion times between the two groups (p<0.05). In conclusion, EIMD significantly affects endurance performance among well-trained athletes through an altered perception of effort.