چکیده:
Introduction: Traditional resistance training increases
strength and power; however, exercises that use the entire
range of motion (ROM) may not provide the optimal
stimulus for enhancing sports performance. The purpose of
this investigation was to compare partial ROM vs. full ROM
lower-body resistance training on hormonal responses and
muscle strength in young women.
Material & Methods: Fourteen young women (age 26.9 ± 5.1
years, height 166.7 ± 5.1 cm, and body mass 62.5 ± 11.8 kg)
voluntary to participate in this study. Volunteers were
randomly assigned to 2 groups: (a) full ROM (FROM; n =
7) or (b) partial ROM (PROM; n = 7). The subjects in
FROM group were introduced to perform hamstring with
machine, squat, dead lift and leg press with 60 to 80 percent
of one repetition maximum (1RM), 3 days a week for 8
weeks. The subjects in PROM group were introduced to
perform that same training with first half ROM and second
half ROM with 50 to 80 percent of 1RM, 3 days a week for 8 weeks. Maximal strength was measured by 1RM before and
after the intervention and growth hormone (GH),
testosterone (Ts), cortisol (Cor) and testosterone to cortisol
ratio (Ts/Cor ratio) were measured at baseline and
immediately and 30 min after the last season of training.
Results: The results indicated that muscle strength in each
station were increased significantly after both of training
methods (P<0.05) and no significant differences were
observed between FROM and PROM methods. Repeatedmeasure
analyses of variance revealed that GH and Ts levels
had not significant changes after the FROM or PROM
resistance training; however, Ts/Cor ratio was increased and
Cor levels were decreased after both of training methods
(P<0.05). For hormonal responses, no significant differences
were observed between FROM or PROM resistance training.
Conclusions: The results suggest that muscle strength and
hormonal responses can be improved with both FROM and
PROM resistance training and there is no significant
difference between these methods.
خلاصه ماشینی:
The influence of variable range of motion training on hormonal responses and muscle strength Reihaneh Esmaeeldokht1 Received: 23 March 2019/ Accepted: 12 May 2019 (1) MS in Exercise Physiology, Department of Exercise physiology, Marvdasht branch, Islamic Azad University, Marvdasht, Iran.
com Abstract Introduction: Traditional resistance training increases strength and power; however, exercises that use the entire range of motion (ROM) may not provide the optimal stimulus for enhancing sports performance.
full ROM lower-body resistance training on hormonal responses and muscle strength in young women.
Although some studies that have investigated the acute effects of performing partial or full ROM (PROM or FROM) strength training have suggested that lifting through a FROM is superior for strength gains when compared with lifting with PROM or mixed ROM (7), but the other studies reported that exercises that use the entire ROM may not provide the optimal stimulus for enhancing sports performance (8,9).
Paired-sample t-test revealed that maximum strength in each station (hamstring with machine, squat, dead lift and leg press) was increased significantly after 8 weeks of FROM and PROM resistance training (P Table 2.
The results of this study suggest that muscle strength and katabolic effect of hormones such as Cor can be improved with both FROM and PROM resistance training.
The results of present study indicated that both of FROM and PROM resistance training equally increases strength gains and hormonal responses can be improved with both of these methods.