Manipulating the Extent of Delayed Onset Muscle Soreness

This is the authors' abstract. We don't add key points for this paper.

PURPOSE: Our purpose was to determine if three discrete levels of soreness can be identified using various magnitudes of eccentric triceps exercise in non-resistance trained, college-aged subjects. METHODS: Twelve male and 12 female subjects were randomly assigned to a 20-, 40-, or 60-repetition group. Subjects performed maximal eccentric triceps contraction at 90°·s[[Unsupported Character - ˉ]]1 on a Cybex isokinetic dynamometer. Measurement of peak torque (PT), arm circumference (2, 6, and 9 cm), relaxed arm angle (RANG), elbow range of motion (ROM), descriptor differential scale (DDS) (sensation and unpleasantness), and creatine kinase (CK) were done at baseline and 24, 48, 72, and 96 h post-soreness induction. A univariate ANOVA on group was also completed after collapsing all time periods and excluding baseline to eliminate a dampening effect of baseline values on group data. RESULTS: A reduction in PT was proportionate to the amount of exercise, as strength decreased by 13.6%, 32.9%, and 47.3% following 20-, 40- and 60-repetitions, respectively, compared to baseline. Arm circumference (2 cm) was significantly different between the 20- and 60- repetition groups, whereas RANG was significantly different between the 20- and 40 and 60 repetition groups. In addition, 60 repetitions reduced ROM more than 20 repetitions. DDS (sensation) was similar for all three groups, but DDS (unpleasantness) was significantly different between the 20 and 60 repetition groups, as was CK. Changes in all variables except CK peaked at 48 h and did not return to baseline until 96 h. CONCLUSION: DOMS can be manipulated into three discrete levels as measured by strength loss (PT) and into two levels when assessed with changes in ROM, RANG, and DDS (unpleasantness). This information may be helpful to researchers, as well as health care and exercise professionals, when assessing treatment and prevention strategies for DOMS.