Abstract:
Introduction: Instability resistance training (IRT) is a combination of unique training movements aimed at improving strength, endurance, coordination, flexibility, power, and core stability within a single workout. The aim of present study was to comparison the effect of instability vs. high-volume resistance training (HVRT) on thigh muscles hypertrophy and hormonal adaptations.Material & Methods: Based on physical health screening, twenty middle-aged men (aged: 26.5 ± 3.6 years; ± SD) selected as the subject. The subjects divided into two groups randomly: HVRT group (n=10) or IRT group (n=10). The subjects in the HVRT group were performed biceps brachii, triceps, chest press, lat pull down, side lateral raise, leg press, dead lift, squat, hamstring and calf sitting with 6 to 10 RMs1in 4 sets and 1 min rest between sets for 8 weeks. The subjects in the IRT group were performed total resistance exercise (TRX) suspension training with 10 rep in 2 sets and20 second rest between the sets for 8 weeks. Paired-sample t-test, independent- sample t-test, wilcoxon and Mann-witneyU teases were use for data analyzing.Results: The results indicated that quadriceps and total thigh muscles cross-sectional area (CSA) were increased after two types of resistance training (P<0.05) and hamstrings CSA was increased only after HVRT method. The data indicated that growth hormone (GH) and testosterone concentration and testosterone/cortisol ratio were increased after HVRT and IRT methods (P<0.05), however for cortisol levels no significant changes were observed.Conclusions: In conclusion, it seems that instability and high volume resistance training-induced changes in anabolic hormones contribute in thigh muscles hypertrophy in untrained men.
Machine summary:
Effects of instability versus high-volume resistance training on thigh muscle cross-sectional area and hormonal adaptations Nooshin Mehrpuya1 and Mehrzad Moghadasi2* Received: 3 November 2018 / Accepted: 11 January 2019 (1) MS student in exercise physiology, Department of Exercise physiology, Marvdasht branch, Islamic Azad University, Marvdasht, Iran.
high-volume resistance training (HVRT) on thigh muscles hypertrophy and hormonal adaptations.
The subjects in the IRT group were performed total resistance exercise (TRX) suspension training with 10 rep in 2 sets and20 second rest between the sets for 8 weeks.
Results: The results indicated that quadriceps and total thigh muscles cross-sectional area (CSA) were increased after two types of resistance training (P Keywords: High volume resistance training, Instability resistance training, TRX training, Hypertrophy, Hormone 1.
A high training volume is associated with an augmented anabolic hormone response to exercise (13,14) that thought to provide an enhanced stimulus for muscle hypertrophy (15,16).
Discussion Resistance training is the most effective way for achieving an acute increase in the concentration of anabolic hormones, which in turn stimulates strength and muscle hypertrophy (24,25).
The amount or time of acute hormonal responses after resistance training may be related to gaining of muscle strength and hypertrophy (26).
Our results indicated that quadriceps CSA and total thigh muscle CSA were increased after 8 weeks HVRT and IRT methods, however hamstring CSA was increased only after HVRT method (P Resistance training, especially among initially untrained healthy subjects, leads to functional and structural adaptations in the neuromuscular system.