The impact of blood flow restricted electrical stimulations on recovery from muscle damage.

Background: Both electrical stimulations (E-STIM) and blood flow restriction (BFR) have been shown to treat symptoms of exercise-induced muscle damage, but little is known about their combined effects which was the purpose of this study.

Methods: Individuals completed one set of eccentric elbow flexion exercises to induce muscle damage. Forty-eight hours later, E-STIM was applied using an interferential current administered to both arms for 20 min; however, only one arm completed the E-STIM protocol while also undergoing repeated bouts of BFR (full occlusion for 2 min separated by a 1-min rest intervals). Discomfort and isometric strength were assessed immediately before the damaging exercise, immediately before the treatments, and 0, 10, and 30 min posttreatment.

Results: A total of 22 individuals (11 females) completed the study. There were no interactions with respect to discomfort (BF  = 0.008) or isometric strength (BF  = 0.009) indicating that the addition of BFR did not alter the effectiveness of E-STIM. There was a main effect of time indicating that the damaging exercise was successful at depressing torque (pre: 284 N, post: 199 N; BF  = 2.70e9) and inducing discomfort (pre: 0 au, post: 6.4 au; BF  = 3.21e17). While isometric strength did not recover with the E-STIM treatments, discomfort was reduced at each the immediate post (5.3 au; BF  = 56 294) 10-min post (5.0 au; BF  = 46 163), and 30-min post (4.9 au; BF  = 707 600) time points.

Conclusion: E-STIM may be useful for treating discomfort, but does not appear capable of recovering strength associated with muscle damage. The efficacy of E-STIM would not appear to be enhanced if performed under BFR.