Objectives: To investigate the effects of multiple cryotherapy applications after muscle injury on markers of oxidative stress.
Methods: Following cryolesion-induced skeletal muscle injury in rats, ice was applied at the injured site for 30 minutes, three times per day, on the day of injury, and for 2 days after injury. To determine the effect of the cryotherapy treatment on markers of oxidative stress, biochemical analyses were performed 3, 7, and 14 days after injury.
Results: Compared with non-treated animals, cryotherapy reduced dichlorofluorescein at 7 and 14 days post-injury and thiobarbituric acid reactive substances levels at 3 and 7 days post-injury (P < 0.05). Additionally, cryotherapy maintained methyl thiazol tetrazolium reduction levels compared to the control group at all analyzed time points (P > 0.05), whereas non-treated groups demonstrated lower levels than the control group (P < 0.05). Superoxide dismutase activity at 7 and 14 days post-injury and catalase activity at 3 days post-injury were lower in cryotherapy groups compared with non-treated groups (P < 0.05). Cryotherapy prevented the reduction of non-protein thiol levels and maintained within control group level, at 3 days post-injury (P = 0.92).
Discussion: Cryotherapy reduced the production of reactive oxygen species after muscle injury, resulting in an attenuated response of the antioxidant system. These findings suggest that using multiple cryotherapy applications is efficient to reduce oxidative stress.
Keywords: Oxidative stress; antioxidants; cryotherapy; physical therapy; regeneration; skeletal muscle; therapeutics.