Low intensity monochromatic infrared therapy: A preliminary study of the effects of a novel treatment unit upon experimental muscle soreness

Background and Objective: The current study (for which ethical approval was obtained) sought to assess the effect of low intensity monochromatic infra red therapy (LIMIRT) on experimentally induced delayed onset muscle sorenes s (DOMS). Study Design/Materials and Methods: Healthy volunteers were recruited (n = 24, 12M:12F) and randomly allocated under strict double blind conditions to one of three experimental groups (n = 8, 4M:4F): Control, Placebo, or Trea tment (840 nm; 3.0 J cm(-2), pulse frequency 1 kHz). DOMS was induced in a standardised manner in the biceps brachii of the nondominant arm. Subjects attended on 5 consecutive days during which the degree of pain and function al impairment was assessed. Results: Analysis of results by using nonparametric Freidman and Kruskal-Wa llis H tests (with relevant post hoc tests) revealed significant difference s (P < 0.05) between Control and LIMIRT treatment groups for pain and tende rness scores. Despite trends in favour of the Treatment group, analysis fai led to show any significant differences between the LIMIRT treatment and Pl acebo groups for all variables except mechanical pain threshold points 3-6 on day 2. Conclusion: The results of the current study suggest that LIMIRT is ineffec tive in the management of DOMS at the parameters investigated. Lasers Surg. Med. 28:33-39, 2001. (C) 2001 Wiley-Liss, Inc.