Cardiorespiratory Adaptations to a Heart Rate Based High Intensity Parallel Squat Resistance Training Program

Abstract

Typical resistance training (RT) does not result in improvements in peak oxygen consumption (VO2peak) in young adults. PURPOSE: To investigate the effects of a 12-week parallel squat resistance training program utilizing aerobic training principles and heart rate training ranges on VO2peak. METHODS: The RT program was designed to comply with ACSM minimal guidelines for increasing cardiorespiratory fitness. Young adult males (n=9) performed parallel squats 3 times per week on non-consecutive days. Each training session consisted of 10 sets of parallel squats with rest periods being determined by HR. The sets were performed as follows: Set 1 = 20 repetitions (reps) at 20% one repetition maximum (1RM); set 2 = 20 reps at 25% 1RM; set 3 = 20 reps at 25% 1RM; set 4 = 20 reps at 30% 1RM; set 5 = 20 reps at 35% 1RM; set 6 = 18 reps at 50% 1RM; set 7 = 15 reps at 65% 1RM; set 8 = 12 reps at 70% 1RM; set 9 = 10 reps at 75% 1RM; set 10 = 8 reps at 80% 1RM. Heart rate was maintained at 55–75% of maximal HR during all training sessions, and sessions lasted 20–30 minutes. Pre- and post training testing included a 1RM parallel squat, an incremental cycle ergometer test to exhaustion (VO2peak), a submaximal cycle ergometer test (VO2submax) at 125 watts, body composition (BC), and thigh cross-sectional area (CSA). A one-way MANOVA revealed a significant within subjects effect of the training program on multiple dependent measures (p = 0.05). Follow-up univariate contrasts were performed to evaluate pre- to post test differences. RESULTS: Group mean data analysis showed a significant 36% increase in 1RM (pre-training = 240.0 ± 62.45 lbs., post training = 324.44± 79.31 lbs., change = 84.44 ± 25.55 lbs.; p =< 0.001), a significant 7.5% increase in CSA (pre-training = 154.66 ± 22.64 cm2, post training = 166.28 ± 23.08 cm2, change = 11.62 ± 7.31 cm2; p = 0.001), and a 6.52% significant decrease in VO2submaxat 125 watts (pre-training = 25.22 ± 2.65 ml/kg/min, post training = 23.57 ± 2.62 ml/kg/min, change = −1.64 ± 1.45 ml/kg/min; p = 0.01). No significant changes were observed in submaximal HR at 125 watts, body weight, or BC. CONCLUSION: Twelve weeks of resistance training, even when designed to comply with ACSM guidelines for increasing cardiorespiratory fitness, increases strength and enhances submaximal exercise performance, but does not result in a significant increase in VO2peak in young adult males.