2009 Studies & Research Blog

We have all heard of resistance type circuit training (CT) and its benefits in relation to the post training elevations in metabolic rate. A new study conducted by Chtara et al. studied whether combining endurance training with CT impacted strength and power.

The parameters they assessed pre- and post-trial were the half squat for maximal strength, the 1-leg half squat and hip extension for strength endurance, and a 5-jump countermovement jump test for explosive strength and power.

To study these variations in training protocols, they assigned college students to 1 of 5 groups: no training controls (C, n = 9), endurance training (E, n = 10), circuit training (S, n = 9), endurance before circuit training in the same session, (E+S, n = 10), and circuit before endurance training in the same session (S+E, n = 10).  

They had the subjects perform 2 sessions per week for 12 weeks. Resistance-type circuit training targeted strength endurance (weeks 1-6) and explosive strength and power (weeks 7-12). Endurance training sessions included 5 repetitions run at the velocity associated equal to 50% and 60 % VO2max.

They found out that the group that performed CT alone had the better improvements in all strength and power tests. Thus, the implications of this research suggests that if strength and power are your goals, then it might be beneficial to avoid endurance events or keep them at a minimum and stick to resistance based workouts such as CT only.

Reference:

Chtara M, Chaouachi A, Levin GT, Chaouachi M, Chamari K, Amri M, Laursen PB. Effect of Concurrent Endurance and Circuit Resistance Training Sequence on Muscular Strength and Power Development. J Strength Cond Res. 2008 Jun 9.