Energy cost of isolated resistance exercises across low- to high-intensities

• Published in: PloS one Vol. 12; no. 7; p. e0181311
• Main Authors: Reis, Victor Machado, Garrido, Nuno Domingos, Vianna, Jeferson, Sousa, Ana Catarina, Alves, José Vilaça, Marques, Mário Cardoso
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 24.07.2017; Public Library of Science (PLoS)
• Subjects: Adult; Aerobics; Biological Oxygen Demand Analysis; Biology and Life Sciences; Body fat; Body mass; Energy; Energy Metabolism; Estimates; Exercise; Group dynamics; Health aspects; Health sciences; Humans; Isometric exercise; Leg; Male; Males; Measurement; Medicine and Health Sciences; Metabolism; Methods; Muscle, Skeletal - physiology; Oxygen - metabolism; Oxygen Consumption; Physical fitness; Physical Sciences; Physical training; Physiological aspects; Physiology; Research and Analysis Methods; Studies; Vanadium oxides; Weightlifting; Young Adult; Portugal
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0181311

This study aimed to estimate the energy cost across various intensities at eight popular resistance exercises: half squat, 45° inclined leg press, leg extension, horizontal bench press, 45° inclined bench press, lat pull down, triceps extension and biceps curl. 58 males (27.5 ± 4.9 years, 1.78 ± 0.06 m height, 78.67 ± 10.7 kg body mass and 11.4 ± 4.1% estimated body fat) were randomly divided into four groups of 14 subjects each. For each group, two exercises were randomly assigned and on different days, they performed four bouts of 5-min constant-intensity for each of the two assigned exercises: 12%, 16%, 20% and 24% 1-RM. Later, the subjects performed exhaustive bouts at 80% 1-RM in the same two exercises. The mean values of VO2 at the last 30s of exercise at 12, 16, 20 and 24% 1-RM bouts were plotted against relative intensity (% 1-RM) in a simple linear regression mode. The regressions were then used to predict O2 demand for the higher intensity (80% 1-RM). Energy cost rose linearly with exercise intensity in every exercise with the lowest mean values were found in biceps curl and the highest in half squat exercise (p<0.001). Half squat exercise presented significant (p<0.001) higher values of energy cost in all intensities, when compared with the remaining exercises. This study revealed that low-intensity resistance exercise provides energy cost comprised between 3 and 10 kcal∙min-1. Energy cost rose past 20 kcal∙min-1 at 80% 1-RM in leg exercise. In addition, at 80% 1-RM, it was found that upper body exercises are less anaerobic than lower-body exercises.