Comparação do custo energético, pico do lactato sanguíneo, percepção subjetiva do esforço e atividade eletromiográfica nos exercícios resistidos em plataformas estável e instável

Abstract

The metabolic impact on energy cost (EC) of resistance exercise (RE) is little known to date in the scientific literature. The various possibilities for organizing training, using different unstable surfaces (US), electromyographic (EMG) activity and the measurement of the anaerobic component in EC, which is often overlooked in studies on RE, can change the value of EC. This study aimed to: 1) compare the acute effect of RE on the circuit training method (CTM) in stable surfaces (SS) and US on the EC, peak blood lactate (PBL) and perceived exertion (PE); 2) compare the EMG activity and strength in 15 repetition maximum bench press and squat free PE and PI. The sample consisted of 20 healthy men (24.65 ± 3.48 years old, 1.79 ± 0.08 m, 80.61 ± 9.14 kg and 11.86 ± 3.49% fat). In the first study we proposed a circuit with seven RS on a SS and an US. We found a higher total EC on US vs. SS (p = 0.01) and total PE (p = 0.02), but the PBL was higher on the SS vs. the US (p = 0.05). We can conclude that the use of US in the CTM is a great alternative for individuals seeking greater energy demand in the RE. In the second study, it was found that the value of the load lifted in the free squat on the SS was significantly higher than on the US (p = 0.001), a difference not found in the bench press (p = 0.231). Regarding the EMG activity, no significant differences were observed in the anterior deltoid (p = 0.06), pectoralis major (p = 0.14), biceps femoris (p = 0.50) and vastuslateralis (p = 0.76) on both surfaces. The US produces a similar EMG activity in relation to SS even using a lower load.