Isometric strength training lowers the O2 cost of cycling during moderate-intensity exercise

• Published in: European journal of applied physiology Vol. 112; no. 12; pp. 4151 - 4161
• Main Authors: Zoladz, Jerzy A., Szkutnik, Zbigniew, Majerczak, Joanna, Grandys, Marcin, Duda, Krzysztof, Grassi, Bruno
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.12.2012; Springer; Springer Nature B.V
• Subjects: Adult; Bicycling; Biological and medical sciences; Biomedical and Life Sciences; Biomedicine; Exercise; Exercise - physiology; Fundamental and applied biological sciences. Psychology; Human Physiology; Humans; Isometric Contraction; Male; Medical screening; Muscle Strength; Occupational Medicine/Industrial Medicine; Original Article; Oxygen Consumption; Physical fitness; Science education; Sports Medicine; Sports training; Strength training; Vertebrates: body movement. Posture. Locomotion. Flight. Swimming. Physical exercise. Rest. Sports; Poland; Exercise; Oxygen uptake kinetics; Strength training; Muscle force; Physical exercise; Human; Physical training; Muscle strength; Cyclism; Intensity; Oxygen consumption; Sport; Kinetics
• ISSN: 1439-6319; 1439-6327
• DOI: 10.1007/s00421-012-2405-x

The effect of maximal voluntary isometric strength training of knee extensor muscles on pulmonary V′ O 2 on-kinetics, the O 2 cost of cycling and peak oxygen uptake ( V′ O 2peak ) in humans was studied. Seven healthy males (mean ± SD, age 22.3 ± 2.0 years, body weight 75.0 ± 9.2 kg, V′ O 2peak 49.5 ± 3.8 ml kg −1  min −1 ) performed maximal isometric strength training lasting 7 weeks (4 sessions per week). Force during maximal voluntary contraction (MVC) increased by 15 % ( P  < 0.001) after 1 week of training, and by 19 % ( P  < 0.001) after 7 weeks of training. This increase in MVC was accompanied by no significant changes in the time constant of the V′ O 2 on-kinetics during 6 min of moderate and heavy cycling intensities. Strength training resulted in a significant decrease (by ~7 %; P  < 0.02) in the amplitude of the fundamental component of the V′ O 2 on-kinetics, and therefore in a lower O 2 cost of cycling during moderate cycling intensity. The amplitude of the slow component of V′ O 2 on-kinetics during heavy cycling intensity did not change with training. Training had no effect on the V′ O 2peak , whereas the maximal power output reached at V′ O 2peak was slightly but significantly increased ( P  < 0.05). Isometric strength training rapidly (i.e., after 1 week) decreases the O 2 cost of cycling during moderate-intensity exercise, whereas it does not affect the amplitude of the slow component of the V′ O 2 on-kinetics during heavy-intensity exercise. Isometric strength training can have beneficial effects on performance during endurance events.