The acute effects of neuromuscular electrical stimulation on coagulation and cardiovascular factors

Neuromuscular electrical stimulation (NMES) can potentially be used to prevent venous thromboembolism; however, its impact on coagulation-related factors remains poorly understood. We aimed to investigate the acute effects on coagulation- and cardiovascular factors immediately after a 2-h NMES session. Levels of overall hemostatic potential (OHP), fibrinogen, factor VIII, and Olink proteomic cardiovascular factors were assessed before and after the NMES session in 36 healthy participants (20 males and 16 females) with a mean age of 31.9 yr. NMES was administered using integrated textile electrodes in pants (NMES pants). Mean intensities during the quadriceps, hamstrings, and gluteus muscle stimulation were 16.5, 20.5, and 25.4 mA, respectively, corresponding to submaximal intensity levels with acceptable discomfort (just below 4 on the visual analogue scale [VAS], 0-10). The NMES session resulted in a significant increase in mean (SD) OHP [94.4 (28.3) to 103 (31.0)], and overall coagulation potential [292 (50.4) to 307(49.8)], and a decrease in overall fibrinolytic potential [68.2 (5.46) to 67.1 (5.20)]. These changes were highly correlated with the increase in fibrinogen (all <i>R</i> > 0.7, <i>P</i> ≤ 0.001), but not with the increase in factor VIII. In addition, 18 of 92 cardiovascular proteins, specifically those involved in regulating inflammation and extracellular matrix remodeling, were influenced by NMES; however, low correlations were found between the changes in these proteins and OHP analyses. In conclusion, the NMES session resulted in a slight increase in the coagulative state, mirroring that seen after a bout of regular exercise. The changes observed in cardiovascular factors, which are mostly not directly related to coagulation, suggest that NMES may subsequently modulate inflammatory responses, warranting further investigation.<b>NEW & NOTEWORTHY</b> The immediate response to a 2-h neuromuscular electrical stimulation (NMES) session, delivered at an acceptable level of discomfort using NMES-pants, marginally increases the coagulative state, similar to what is observed after regular physical exercise. This change is not expected to significantly increase the risk of blood clotting, as all factors remain within the normal reference range. Interestingly, NMES simultaneously appears to affect proteins that regulate the transition of inflammation into an anti-inflammatory response.