The effect of warm-up on delayed onset muscle soreness.

Purpose: The aim of this experiment was to investigate if a warm-up period prior to eccentric exercise has a preventive effect on the increased sensitivity to pain, and the loss of force, associated with delayed onset muscle soreness (DOMS). Methods: Twenty-four subjects were randomly assigned into a warm-up group (N=12) or a control group (N=12). The warm-up group completed 20 minutes of ergometer cycling, with an intensity of 60-70 % of estimated maximal heart rate, prior to eccentric exercise, while the control group did not perform warm-up prior to the eccentric exercise. DOMS was induced by completing 5 sets of 10 forward lunges (eccentric exercise). The outcome measures were: subjective evaluation of pain on a 100 mm. visual analogue scale (VAS), a pressure-pain threshold (PPT) on various locations of the m. rectus femoris, and isometric maximal voluntary contraction force (MVC), collected prior to exercise, 24-and 48 hours following exercise. Results: Both groups had significantly lower PPT in the distal region of the m. rectus femoris 24 hours following eccentric exercise. However, only the control group had a significant decrease in PPT in the proximal region of the m. rectus femoris. In addition, the warm-up group developed significantly less pain than the control group in the proximal region of the m. rectus femoris between baseline and 24 hours following exercise. Both groups had a significant decrease in MVC, and more pain (VAS) following exercise. Moreover, there were no significant differences between groups in MVC and VAS 24 and 48 hours following exercise. Conclusion: Our results suggest that warm-up prior to eccentric exercise might have a preventive effect on DOMS measured as the pressure pain threshold. The preventive effect seems to be most prominent in the proximal region of the muscle 24 hours following exercise. Key words: Warm-up, delayed onset muscle soreness, DOMS, eccentric exercise, pressure-pain threshold, PPT, visual analogue scale, VAS, maximal voluntary contraction forc