The use of sub-tetanic low intensity neuromuscular electrical stimulation (NMES) with the aim of promoting recovery from exercise has increased in recent years. The goal of this systematic review was to assess the effects of NMES on exercise recovery. A computerised database search of PubMed, CINAHL Plus, Sport Discus and Cochrane Library electronic databases was conducted for the time period Jan 1 1970 to Mar 8 2012. Only studies which used healthy uninjured humans and motor-threshold electrical stimulation compared to at least one other recovery modality for the purpose of promoting recovery from exercise were eligible for selection. Thirteen studies met the inclusion criteria and were included for analysis (11 randomised crossover trials (RXT’s), 1 randomised control trial (RCT) and 1 classified as other (OTH)). A quality assessment rating of the studies was performed using an extended version of The Cochrane Collaboration’s Tool for Assessing Risk of Bias. Because of the heterogeneity of the study protocols, a qualitative review (best evidence synthesis) was performed for all outcomes, while the results for blood lactate (BLa) were included as well in a meta-analysis. Eight studies were classified as high quality, 4 as medium quality, and one as low quality. Three studies found a positive outcome for a subjective measure of muscle pain, 3 for BLa, one for lowering creatine kinase, and only one for a performance parameter. The meta-analysis did not show any evidence in favour of NMES vs. active (ACT) and mixed evidence vs. passive (PAS) recovery for BLa.
In conclusion, although there may be some subjective benefits for post-exercise recovery, evidence is not convincing to support NMES for improving resultant performance.