Effects of 6 Weeks of Traditional Resistance Training or High Intensity Interval Resistance Training on Body Composition, Aerobic Power and Strength in Healthy Young Subjects: A Randomized Parallel Trial

Abstract

Consistent practice of physical activity has well known positive effects on general health; however, time for exercise remains one major barrier for many. An acute bout of high intensity interval resistance training (HIIRT) increases acute resting energy expenditure (REE) and decreases respiratory ratio (RR), suggesting its potential role on weight loss and increased fatty acid oxidation. The aim of this study was to test the long-term effect of HIIRT on body composition, lipid profile and muscle strength using a randomized parallel trial. Twenty healthy young adults (22.15 ± 1.95 years) were randomized to perform either a HIIRT (N = 11) protocol, consisting of three sets of 6 repetitions at 6 repetition maximum (RM) and then 20 seconds of rest between repetitions until exhaustion repeated for 3 times with 2′30″ rest between sets or a traditional training (TRT, N = 9) protocol of 3 sets of 15 reps with 75 sec of rest between sets. Body composition, resting energy metabolism, aerobic capacity, muscle strength and blood measurements were taken before and after 8 weeks of training. Both protocols enhanced muscle strength, but only HIIRT improved endurance strength performance (+22.07%, p < 0.05) and lean body mass (+2.82%, p < 0.05). REE and RR were unaltered as lipid profile. HIIRT represents a valid training method to improve muscle strength and mass, but its role on body weight control was not confirmed.

Using Machines or Free Weights for Resistance Training in Novice Males? A Randomized Parallel Trial

“…In the present study, significant increases in upper arm, thigh, and chest circumferences were found for all RT groups when comparing pre-, mid-, and post-intervention outcomes over the 10-week RT program applied. This positive change over time in these anthropometric estimations of muscle size is an expected result as a 10-week RT program should be sufficiently long to induce hypertrophic effects in the untrained [19,[29][30][31]. Seynnes et al (2006) observed that changes in muscle size were already detectable after three weeks of RT in recreationally active young healthy males [19].…”

“…Seynnes et al (2006) observed that changes in muscle size were already detectable after three weeks of RT in recreationally active young healthy males [19]. Interestingly, in the study of Moro et al (2020) hypertrophic effects were only observed in recreationally active men who engaged in 8 weeks of high intensity interval RT but not in their peers performing traditional RT [31]. Muscular adaptation and the role of fitness level, training volume, intensity, and periodization are indeed topics that can further be explored [32].…”

Effects of a Low-Carbohydrate High-Fat Diet Combined with High-Intensity Interval Training on Body Composition and Maximal Oxygen Uptake: A Systematic Review and Meta-Analysis

“…However, unlike these dietary approaches, exercise interventions, such as high-intensity interval training (HIIT) or resistance training (RT), are known to bring beneficial changes in body function and composition, which imply the combination with exercise may counteract this negative effect. It is now well established from various studies that HIIT or RT improve physical function (e.g., ameliorate insulin resistance [24,25], reduce liver fat accumulation [26,27], decrease cardiovascular disease risk [28,29], improve aerobic capacity [30,31], enhance muscle strength [32], and increase LM and FFM [21,30,33,34] [21 (RCT), 30 (RCT), 33 (RCT), 34 (RCT)]. The benefits of HIIT and RT on LM and FFM are attributed to increased energy expenditure due to muscle contraction, which enhances adipose metabolism in muscle tissue and muscle growth-related factor gene expression [35].…”

Effects of High-Intensity Interval Training Protocols on Liver Enzymes and Wellness in Women

“…The effects of exercise on ALT and AST are less clear in healthy adults. While both aerobic and resistance exercise can decrease ALT in patients with nonalcoholic fatty liver disease [ 10 ], a study by Moro et al [ 11 ] found no change in ALT or AST in healthy young adults following interventions involving high-intensity interval resistance training or resistance training. Furthermore, a study by Skrypnik et al [ 12 ] found that the combination of resistance and endurance training was more effective than endurance training alone in improving liver function in females with abdominal obesity.…”