Effects of ultrasound and trolamine salicylate phonophoresis on delayed-onset muscle soreness.

The purpose of this study was to determine the effects of ultrasound and phonophoresis using an anti-inflammatory-analgesic cream (trolamine salicylate) on delayed-onset muscle soreness (DOMS). Repeated eccentric contractions were used to induce DOMS in the elbow flexors of 40 college-aged women. Subjects were then assigned randomly to one of four groups: (1) group 1 (n = 10) received sham ultrasound using placebo cream, (2) group 2 (n = 10) received sham ultrasound using trolamine salicylate cream, (3) group 3 (n = 10) received ultrasound using placebo cream, and (4) group 4 (n = 10) received ultrasound using trolamine salicylate cream. Subjects were treated on 3 consecutive days. Muscle soreness and active elbow range of motion were assessed daily prior to each treatment. The subjects in group 3 experienced an increase in DOMS, whereas no increase in soreness was observed in the subjects in group 4. The authors concluded that ultrasound enhanced the development of DOMS but that this enhancement was offset by the anti-inflammatory-analgesic action of salicylate phonophoresis. These findings suggest that salicylate phonophoresis may be useful in clinical situations in which it is desirable to administer ultrasound without increasing inflammation.