The Chronic Effects of Low- and High-Intensity Resistance Training on Muscular Fitness in Adolescents

• Published in: PloS one Vol. 11; no. 8; p. e0160650
• Main Authors: Assunção, Ari R, Bottaro, Martim, Ferreira-Junior, João B, Izquierdo, Mikel, Cadore, Eduardo L, Gentil, Paulo
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 10-08-2016; Public Library of Science (PLoS)
• Subjects: Adolescent; Adolescents; Analysis; Biology and Life Sciences; Body composition; Chest; Child development; Children & youth; Chronic effects; College campuses; Endurance; Exercise; Female; Fitness; Health aspects; Health sciences; Humans; Load; Load resistance; Male; Medicine and Health Sciences; Mens health; Muscle, Skeletal - physiology; People and Places; Physical education; Physical Endurance; Physical Fitness; Physical training; Repetition; Resistance training; Resistance Training - methods; Sports training; Strength training; Studies; Teenagers; Training; Weight training; Youth; United States
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0160650

To compare the effects of high-load, low-repetition maximum (LRM) and low-load, high-repetition maximum (HRM) resistance training regimens on muscular fitness in untrained adolescents. Forty-five untrained adolescents of both sexes (13.7±0.8 years; 161.3±7.5 cm, 56.8±13.4 kg) were randomly assigned into one of three groups: 1) LRM (n = 17): volunteers performed three sets of 4-6-repetition maximum (RM); 2) HRM (n = 16): volunteers performed three sets of 12-15 RM; and 3) control (CON, n = 12). Training was performed two times a week for 9 weeks. After training, there were significant increases in 1 RM chest press (LRM = 14.8% and HRM = 14.2%, p<0.05) and squat (LRM = 26.4% and HRM = 25.7%, p<0.05), with no differences between the LRM and HRM groups (p>0.05). Additionally, muscular endurance increased significantly for the chest press (LRM = 14.5% and HRM = 21.8%, p<0.05) and squat test (LRM = 31.4% and HRM = 32.4%, p<0.05) following resistance training, with no difference between the LRM and HRM groups (p>0.05). These results suggest that both high-load, low-repetition and moderate-load, high-repetition resistance training can be prescribed to improve muscular fitness in untrained adolescents.