Effects of Stochastic Resonance on Sensorimotor Performance during Exercise-Induced Muscle Damage

The aim of this study was to assess the effects of stochastic resonance (SR) stimulation on sensorimotor performance during an episode of exercise-induced muscle damage (EIMD). Thirty four men (age: 21.3 (±2.6) years; height 1.78 (±0.06) m; body mass 72.3 (±7.4) kg (mean (±SD)) gave their informed consent to participate in this study.Sensorimotor performance (error in replicating a target force) of the knee flexors was assessed prior to, and at 0.5 and 48 h after (i) a treatment condition involving a single-leg EIMD conditioning of the non-preferred leg, with concomitant responses to (ii) randomised presentation of SR, no SR and placebo conditions. Results showed a significant ANOVA interaction for sensorimotor performance amongst factors of condition (control period; EIMD), time (pre; post 0.5 h; post 48 h) and stimuli (SR; no SR; placebo) (F[1.5,29.3] = 5.7; p < 0.01). While scores during an antecedent control period had remained relatively constant, the EIMD protocol had elicited increased error in replicating a target force for the knee flexors of the non-preferred leg over time (worsened sensorimotor performance) that had been most prominent at 48 h after exercise, but whose negative effects had been ameliorated under conditions of SR (5.6 ± 3.1% (no SR) versus 3.7 ± 2.3% (SR) (pre) and 10.3 ± 4.2% (no SR) versus 8.1 ± 5.1% (SR) (48 h), respectively; F[1,36] = 6.0; p < 0.01). In conclusion, this study has shown that SR conditioning-related increases in the sensorimotor performance of the hamstring muscle group led to some protection from performance loss following EIMD.