Comparing the effects of 25-minute electrical muscle stimulation vs. 90-minute full-body resistance training on body composition and strength: A 20-week intervention

Objectives: Electromyostimulation (EMS) and traditional resistance training (TradRT) are widely used methods for improving muscle strength and body composition. However, comparative studies employing a multi-week longitudinal design remain limited. This study aimed to investigate the effects of 20 weeks of EMS vs. TradRT on body composition and strength performance in physically active adults.

Methods: Forty-six participants were randomly assigned to either the EMS group (n = 22) or the TradRT group (n = 24). The EMS group performed twice-weekly, 25-min whole-body EMS sessions, while the TradRT group completed twice-weekly, 90-min full-body resistance training sessions.

Results: Assessments of body weight, body mass index (BMI), fat percentage, and maximal strength were conducted at baseline, 10 weeks, and 20 weeks. A significant time effect was observed for all variables (p < 0.001), indicating improvements in both groups. However, group x time interactions revealed distinct adaptation patterns. The TradRT group exhibited greater reductions in body fat percentage and superior strength gains in bench press, leg press, shoulder press, and triceps pushdown, and abdominal strength. Conversely, the EMS group showed greater reductions in body weight and BMI. No significant interaction effect was observed for biceps curl strength. Both EMS and TradRT were effective in improving strength and body composition, but TradRT led to greater strength development and fat reduction, while EMS was more effective for weight and BMI reduction. Conclusions: These findings suggest that EMS may serve as a viable alternative for individuals unable to engage in high-load resistance training, whereas TradRT remains superior for maximizing strength and fat loss.