The effects of one session of roller massage on recovery from exercise-induced muscle damage: A randomized controlled trial.

BACKGROUND/OBJECTIVE: Roller massage has become a popular intervention in sports settings in order to treat muscle soreness and stiffness, as well as improving post-exercise recovery, although there is limited evidence for these assumptions. Therefore, the purpose of this study was to evaluate the effects of a single session of roller massage, applied with a controlled force after an exercise-induced muscle damage protocol, on muscle recovery. METHODS: A randomized controlled study was performed using a repeated-measures design. Thirty-six young men completed four sets of six eccentric actions of elbow flexors at 90°/s with a 90s rest interval between sets. Participants were randomly assigned into one of three groups: 1) Roller massage (n = 12), 2) Sham (n = 12), and 3) Control (n = 12). Maximal isometric voluntary contraction (MIVC), delayed-onset muscle soreness (DOMS), range of motion (ROM), and muscle thickness were measured at baseline, and at 24, 48, and 72 h post exercise. RESULTS: There was no significant group by time interaction for MIVC (p = 0.090) and ROM (p = 0.416). Also, although there was a significant group by time interaction for muscle thickness (p = 0.028), post hoc test did not find significant difference between groups (p > 0.05). DOMS was recovered at 72 h for roller massage (p < 0.001) and control (p < 0.001) groups, while the Sham group did not recover from DOMS across 72 h (p < 0.001). There was also no significant difference between groups in DOMS at any time (p > 0.05). CONCLUSIONS: A single session of roller massage applied on elbow flexors had no effect on recovery of MIVC, muscle swelling, ROM and DOMS.

Skinfold thickness affects the isometric knee extension torque evoked by Neuromuscular Electrical Stimulation.

BACKGROUND: Subcutaneous adipose tissue may influence the transmission of electrical stimuli through to the skin, thus affecting both evoked torque and comfort perception associated with neuromuscular electrical stimulation (NMES). This could seriously affect the effectiveness of NMES for either rehabilitation or sports purposes. OBJECTIVE: To investigate the effects of skinfold thickness (SFT) on maximal NMES current intensity, NMES-evoked torque, and NMES-induced discomfort. METHOD: First, we compared NMES current intensity, NMES-induced discomfort, and NMES-evoked torque between two subgroups of subjects with thicker (n=10; 20.7 mm) vs. thinner (n=10; 29.4 mm) SFT. Second, we correlated SFT to NMES current intensity, NMES-induced discomfort, and NMES-evoked knee extension torque in 20 healthy women. The NMES-evoked torque was normalized to the maximal voluntary contraction (MVC) torque. The discomfort induced by NMES was assessed with a visual analog scale (VAS). RESULTS: NMES-evoked torque was 27.5% lower in subjects with thicker SFT (p=0.01) while maximal current intensity was 24.2% lower in subjects with thinner SFT (p=0.01). A positive correlation was found between current intensity and SFT (r=0.540, p=0.017). A negative correlation was found between NMES-evoked torque and SFT (r=-0.563, p=0.012). No significant correlation was observed between discomfort scores and SFT (rs=0.15, p=0.53). CONCLUSION: These results suggest that the amount of subcutaneous adipose tissue (as reflected by skinfold thickness) affected NMES current intensity and NMES-evoked torque, but had no effect on discomfort perception. Our findings may help physical therapists to better understand the impact of SFT on NMES and to design more rational stimulation strategies.

Skinfold thickness affects the isometric knee extension torque evoked by Neuromuscular Electrical Stimulation

BACKGROUND: Subcutaneous adipose tissue may influence the transmission of electrical stimuli through to the skin, thus affecting both evoked torque and comfort perception associated with neuromuscular electrical stimulation (NMES). This could seriously affect the effectiveness of NMES for either rehabilitation or sports purposes. OBJECTIVE: To investigate the effects of skinfold thickness (SFT) on maximal NMES current intensity, NMES-evoked torque, and NMES-induced discomfort. METHOD: First, we compared NMES current intensity, NMES-induced discomfort, and NMES-evoked torque between two subgroups of subjects with thicker (n=10; 20.7 mm) vs. thinner (n=10; 29.4 mm) SFT. Second, we correlated SFT to NMES current intensity, NMES-induced discomfort, and NMES-evoked knee extension torque in 20 healthy women. The NMES-evoked torque was normalized to the maximal voluntary contraction (MVC) torque. The discomfort induced by NMES was assessed with a visual analog scale (VAS). RESULTS: NMES-evoked torque was 27.5% lower in subjects with thicker SFT (p=0.01) while maximal current intensity was 24.2% lower in subjects with thinner SFT (p=0.01). A positive correlation was found between current intensity and SFT (r=0.540, p=0.017). A negative correlation was found between NMES-evoked torque and SFT (r=-0.563, p=0.012). No significant correlation was observed between discomfort scores and SFT (rs=0.15, p=0.53). CONCLUSION: These results suggest that the amount of subcutaneous adipose tissue (as reflected by skinfold thickness) affected NMES current intensity and NMES-evoked torque, but had no effect on discomfort perception. Our findings may help physical therapists to better understand the impact of SFT on NMES and to design more rational stimulation strategies.