Machines versus Free Weights

Abstract

Resistance exercise reduces the risk of chronic disease and promotes numerous health benefits. Due to the low rates of participation in resistance exercise, research is needed to create a more positive affective response from exercise. This has been shown to increase rates of adherence in aerobic exercise. PURPOSE: To compare the affective responses of performing resistance exercise on machines (MA) and free weights (FW). METHODS: Novice participants (4 Males: 20.8±0.5yrs; 75.2±17kg; 180±2.4cm; 14 Females: 25.7±9.8yrs; 67.9±19kg; 163±5.6cm) completed a MA workout consisting of the leg press, row, chest press, and leg curl and a FW workout consisting of a goblet squat, row, bench press, and stiff leg deadlift. Each exercise was performed at 80% 10RM for 3 sets of 9-11 repetitions with 90 secs of rest between each set. Feeling Scale (FS) and Felt Arousal Scale (FAS) were assessed before exercise, after the completion of the 7th repetition of the 2nd set of each exercise, after the 3rd set of each exercise, immediately after, 30 min after, and 60 min after. RESULTS: Repeated measures ANOVA from before to after exercise revealed a condition x time interaction for FS where FS in the MA condition increased immediately and 60 minutes following exercise, there was no change across time for FW, and FS for MA was significantly higher at 60 minutes following exercise than FW, F(3, 51) = 3.26, p = 0.040. For FAS before and after exercise, FAS significantly increased immediately following exercise and then decreased to below exercise levels at 30 and 60 min regardless of condition, F(3, 51) = 11.91, p < 0.001. Repeated measures ANOVA for RPE during the exercise revealed a condition x time interaction where RPE was higher in FW for all exercises except those of the chest where RPE was higher for MA, F(7, 119) = 3.285, p = 0.015. CONCLUSION: The more positive affective response from the MA workout immediately and 60 minutes after exercise suggests that MA exercises may be better for novice lifters when beginning a resistance training regimen.