ABSTRACT
Recent studies have observed that stretching applied to antagonist muscles can promote improvement in agonist muscle performance. The purpose of this study was to investigate the effect of different numbers of interset proprioceptive neuromuscular facilitation (PNF) stretching for the antagonists on the total number of repetitions completed for the agonists (quadriceps) in the leg extension exercise. Fourteen physically active individuals (age: 29.35 ± 10.5 years; body mass: 79.1 ± 11.34 kg; height: 170.4 ± 8.7 cm) participated in this study. The following experimental protocols were performed: 1) Traditional protocol (Traditional) - without previous stretching; 2) PNF with lesser duration (PNF1-3 sets of 20 secs.); 3) PNF with greater duration (PNF2-3 sets of 30 secs.). Within the experimental protocols (PNF1 and PNF2), stretching exercises for the antagonists were performed before and between the four sets of the unilateral leg extension exercise. All tests were performed on the dominant limb only. The results showed that there was a significant difference in the total number of repetitions for the PNF2 protocol versus the Traditional protocol (p = 0.026). However, there was no significant difference between the PNF1 protocol versus the Traditional protocol (p = 0.577). In conclusion, in the leg extension exercise, an extended duration of interset PNF stretching for the hamstrings, promoted greater contractile performance for the quadriceps as demonstrated by significantly greater total repetitions over four sets.
ABSTRACT
ABSTRACT: Filho, MM, Venturini, GRdO, Moreira, OC, Leitão, L, Mira, PA, Castro, JB, Aidar, FJ, Novaes, JdS, Vianna, JM, and Caputo Ferreira, ME. Effects of different types of resistance training and detraining on functional capacity, muscle strength, and power in older women: A randomized controlled study. J Strength Cond Res 36(4): 984-990, 2022-Resistance training (RT) increases muscle strength, power, and functional capacity (FC) of older women. However, these benefits can be lost partially or totally with detraining. This study aimed to compare the effect of 20 weeks of different types of RT and 4 weeks of detraining on muscle strength, power, and FC in older women. Ninety-five older women were randomly divided into 4 experimental groups (strength endurance, power, absolute strength, and relative strength training) and 1 control group (CG). We assessed muscle strength (10RM test) and muscle power of the lower (countermovement jump) and upper limbs (medicine ball pitch). Functional capacity was assessed by the Senior Fitness Test, which comprises the following tests: 30-second arm curl, 30-second chair stand, back scratch, chair sit and reach, 8-foot up and go, and 6-minute walk. The experiment lasted 24 weeks (familiarization: 2 weeks; neural adaptation: 6 weeks; specific training: 12 weeks; and detraining: 4 weeks). Muscle strength, lower and upper limb power (all p < 0.05), 30-second arm curl, 30-second chair stand, 8-foot up and go, 6-minute walk (all p < 0.001), and lower limb flexibility (p = 0.002) improved in all experimental groups after training and CG showed no differences in any of these variables. After detraining, muscle strength, lower and upper limb power (p < 0.05 for all), and FC decreased in comparison to the end of RT (30-second arm curl, 30-second chair stand, 8-foot up and go, 6-minute walk, and lower limb flexibility, p < 0.05 for all). Although the FC of the subjects has been reduced after 4 weeks of detraining, it was maintained at higher levels in comparison to baseline. These results suggested that older women can be submitted to different types of RT to achieve improvements in general fitness.
