ABSTRACT
Introduction:
Circuit training is a model of resistance exercise that allows a varied combination of overload and therefore, requires more information to understand the anaerobic glycolytic demand during its execution.
Objective:
The objective was to compare two weight training protocols with (Tconv) and without (Tcirc) pause between performances, regarding the blood lactate ([la]) response.
Methods:
Eleven men (21.0±2.3 years old, 76.7±5.4 kg, 179.5±7.0 cm) underwent to one-maximum repetition test (1RM). Tconv and Tcirc were prescribed at 60%1RM, 12 repetitions, three laps with 300 s rest for Tcirc and three series of exercise with 180 s rest for Tconv. The exercises that comprised both training protocols were bench press, unilateral leg extension, shoulder press, double leg curl, high pulley, leg press 45º, seated row and hack-squat. The ANOVA (Bonferroni post-hoc) test compared [la] at the 1st, 3rd e 5th minute after the Tcirc laps and after each Tconv series. The independent t-test compared the means of the lactate peak between Tcirc and Tconv. In all analyzes the level of significance was set at P≤0.05.
Results:
Differences were observed for the [la] between the 1st (10.6±1.0 mmol/l) and 2nd lap (13.5±1.8 mmol/l, P=0.01), and between 1st and 3rd lap (15.0±2.5 mmol/L, P<0.01) in the Tcirc. During Tconv, the highest mean peak values of [la] were observed in high pulley (11.2±2.2 mmol/l) and leg-press 45º (11.9±2.6 mmol/l) exercises. There was a difference (P<0.01) when comparing the [la] between after Tconv (12.8±2.2 mmol/l) and Tcirc (15.9±2.0 mmol/l).
Conclusion:
Tcirc demands greater glycolytic response, emphasizing its effectiveness to increasing anaerobic muscle capacity. Furthermore, the non-intermittent execution of Tcirc can explain its greater glycolytic demand, since Tconv and Tcirc were proportionally designed regarding the volume and load protocol. Level of Evidence I; Diagnostic studies - Investigating a Diagnostic Test.
Keywords:
Circuit-based exercise; Lactic acid; Resistance training.
