Effects of Different Volumes of Resistance Training on Body Composition, Peak Power, and Muscle Thickness in Untrained Healthy Women

The study aimed to investigate the effect of different resistance training volume (low-, moderate, and high) on body composition, maximal strength, peak power, and muscle thickness in untrained women over eight weeks. The study is a three-arm, randomized controlled trial, 45 female college students participated, fit the specific inclusion criteria like age between 18-65 and being untrained. Exclusion criteria included the use of performance-enhancing drugs or recent resistance training.

Participants were randomly assigned to one of three groups: low-volume training (LVT) with three sessions weekly, moderate-volume training (MVT) with four sessions weekly, and high-volume training (HVT) with five sessions weekly. Each session comprised 12 exercises. Split split-strength training method was applied. After participants' 1RM maximums were determined, training loads were calculated separately for each participant. All workouts were conducted by certified trainers to ensure they were performed in the correct training format. Each training session lasted approximately 60 minutes. The weekly training loads of all participants were increased by 5%. In the LVT group, 3 sets of 8-12 repetitions of: between sets interval: 120 seconds (3 days/wk), in the MVT group, 3 sets of 8-12 repetitions of: between sets interval: 120 seconds (4 days/wk), in the HVT group, 3 sets of 8-12 repetitions of: between sets interval: 120 seconds exercises (5 days/wk) were performed.

Results and data analysis involved anthropometric measurements, muscle thickness via ultrasound, and peak power from the vertical jump test. Statistical significance was set at p < 0.05, and effect sizes were calculated with Partial Eta Squared values.