Continuous low-level heat wrap therapy for the prevention and early phase treatment of delayed-onset muscle soreness of the low back: a randomized controlled trial.

OBJECTIVE

To evaluate the effects of continuous low-level heat wrap therapy for the prevention and early phase treatment (ie, 0-48 h postexercise) of delayed-onset muscle soreness (DOMS) of the low back.

DESIGN

Two prospective randomized controlled trials.

SETTING

Outpatient medical facility.

PARTICIPANTS

Sixty-seven subjects asymptomatic of back pain and in good general health (mean age, 23.5+/-6.6 y).

INTERVENTIONS

Participants performed vigorous eccentric exercise to experimentally induce low back DOMS. Participants were assigned to 1 of 2 substudies (prevention and treatment) and randomized to 1 of 2 treatment groups within each substudy: prevention study (heat wrap, n=17; control [nontarget muscle stretch], n=18) and treatment study (heat wrap, n=16; cold pack, n=16). Interventions were administered 4 hours before and 4 hours after exercise in the prevention study and between hours 18 to 42 postexercise in the treatment study.

MAIN OUTCOME MEASURES

To coincide with the expected occurrence of peak symptoms related to exercise-induced low back DOMS, hour 24 postexercise was considered primary. Pain intensity (prevention) and pain relief (treatment) were primary measures, and self-reported physical function and disability were secondary measures.

RESULTS

In the prevention study, at hour 24 postexercise, pain intensity, disability, and deficits in self-reported physical function in subjects with the heat wrap were reduced by 47% (P<.001), 52.3% (P=.029), and 45% (P=.013), respectively, compared with the control group. At hour 24 in the treatment study, postexercise, pain relief with the heat wrap was 138% greater (P=.026) than with the cold pack; there were no differences between the groups in changes in self-reported physical function and disability.

CONCLUSIONS

In this small study, continuous low-level heat wrap therapy was of significant benefit in the prevention and early phase treatment of low back DOMS.