Hypoalgesic effects of a blood flow restriction technique at moderate intensity with or without motor imagery: a single-blind randomized controlled trial.

PURPOSE: The main objective was to assess the hypoalgesic effect of adding blood flow restriction (BFR) training with or without motor imagery (MI) to moderate-intensity exercise. The secondary objective was to analyse the correlations of the pain pressure thresholds (PPTs) regarding perceived pain intensity, perceived fatigue, and cuff pressure discomfort. METHODS: A sample of 42 asymptomatic participants were randomly assigned to 3 groups: control group (CG), BFR group, and BFR with MI group. All participants performed a squat exercise at an intensity of 60% of 1RM. For the BFR groups, blood occlusion occurred at 80% of maximal arterial occlusive pressure. Local, bilateral, and distal PPT were assessed pre-intervention, post-intervention and 48 h post-intervention. The perceived fatigue was assessed post-intervention, and pain intensity was assessed only 48 h post-intervention. RESULTS: There were intragroup differences in the CG and BFR + MI group in the local PPT between the pre-intervention and post-intervention measurements (p = 0.039, d= -0.32 and p = 0.009, d= -0.46, respectively) and only in the CG in the bilateral PPT (p = 0.002, d= -0.41). The CG and BFR group showed significant differences at 48 h post-intervention, with a decrease in local PPT (p = 0.009, d = 0.51 and p = 0.049, d = 0.43, respectively) and bilateral PPT (p = 0.004, d = 0.53 and p = 0.021, d = 0.46, respectively). There was a negative moderate correlation between local PPT at the post-intervention time and perceived discomfort of the occlusion device only in the BFR group (r=-0.54, p = 0.045). CONCLUSION: Moderate-intensity resistance training with high occlusion did not generate hypoalgesia but did appear to generate a hyperalgesic response within 48 h after the intervention.

Effectiveness of motor imagery and action observation on functional variables: An umbrella and mapping review with meta-meta-analysis.

To assess the current evidence on motor imagery (MI) and action observation (AO) and their influence on functional variables. We conducted 3 meta-meta-analyses (MMA) to determine the effectiveness of MI and AO on arm functionality, performance on activities of daily living and gait mobility in stroke patients. For arm functionality, MMA revealed a statistically significant large effect size (standardised mean difference [SMD] = 1.05; 95 % CI 0.50-1.60; p<.001) but with evidence of heterogeneity (Q=55.67, p<.001, I2=93 %). For arm performance in activities of daily living, MMA revealed a significantly large effect size (SMD=1.76; 95 % CI 1.10-2.43; p<.001) but also with evidence of heterogeneity (Q=1.62, p=.44, I2=90 %). MMA showed no significant effects favouring intervention regarding gait mobility. The results of the systematic reviews showed that movement representation techniques combined with the usual treatment have a positive impact on improving function, with a very low to moderate quality of evidence for all variables except for range of motion in acute disorders and strength. MI and AO showed positive results for improving functional variables.

Effect of brain training through visual mirror feedback, action observation and motor imagery on orofacial sensorimotor variables: A single-blind randomized controlled trial.

OBJECTIVES: The main objective was to evaluate the effects of action observation (AO), visual mirror feedback (VMF) and motor imagery (MI), combined with an oro-facial exercise programme, on sensorimotor variables in asymptomatic participants. METHODS: We designed a randomised, single-blind, controlled trial that included 52 asymptomatic participants who were randomly assigned to 4 groups, 13 to each of the VMF, MI and AO groups and 13 to the control group (CG), which only performed the exercise programme. The primary outcomes were pain pressure sensitivity and tongue muscle strength. The secondary outcomes were maximum mouth opening, tongue length and the ability to generate mental motor images. Each group underwent a 3-session intervention using their respective exercise. Measurements were performed before starting the intervention and after each of the 3 sessions (pre, mid1, mid2 and post). RESULTS: ANOVA revealed significant changes in PPTs in the masseter muscle region in the MI and AO groups in the pre-post and mid1-post changes. ANOVA revealed significant differences in tongue muscle strength in the anterior direction only in the AO group in the pre-mid2 and pre-post changes. CONCLUSIONS: AO and MI, in conjunction with exercise, could induce changes in PPTs for the masseter muscle. In addition, only AO produced changes in tongue muscle strength. More research is needed to determine the role of brain representation techniques in the oro-facial region and transferring this exercise to the rehabilitation setting.