Endurance training-induced increase in muscle oxidative capacity without loss of muscle mass in younger and older resistance-trained men

• Published in: European journal of applied physiology 2021-11, Vol.121 (11), p.3161-3172
• Main Authors: Hendrickse, Paul William, Venckunas, Tomas, Platkevicius, Justinas, Kairaitis, Ramutis, Kamandulis, Sigitas, Snieckus, Audrius, Stasiulis, Arvydas, Vitkiene, Jolanta, Subocius, Andrejus, Degens, Hans
• Format: Article
• Language: English
• Subjects: Adaptation; Adaptation, Physiological - physiology; Adult; Aerobics; Aged; Biomedical and Life Sciences; Biomedicine; Biopsy; Body mass; Capillaries; Endurance Training; Heart rate; Human Physiology; Humans; Leg - diagnostic imaging; Leg - physiology; Magnetic Resonance Imaging; Male; Muscle contraction; Muscle, Skeletal - diagnostic imaging; Muscle, Skeletal - metabolism; Muscles; Occupational Medicine/Industrial Medicine; Original; Original Article; Oxygen consumption; Oxygen Consumption - physiology; Physical training; Resistance Training; Sports Medicine; Strength training; Succinate dehydrogenase
• ISSN: 1439-6319; 1439-6327
• DOI: 10.1007/s00421-021-04768-4

While concurrent training is regularly used in older populations, the inverse relationship between fibre size and oxidative capacity suggests that endurance training in resistance-trained individuals may result in some loss of resistance training-induced gains in muscle mass, which may be more pronounced in older people. We investigated the impact of superimposed endurance training in younger (28.5 ± 4.8 years; n  = 8) and older (67.5 ± 5.5 years; n  = 7) highly resistance-trained men. Participants underwent a 10-week endurance cycling training programme consisting of five 6-min intervals at 75% max heart rate (HRmax) separated by 4-min intervals at 90% HRmax. The anatomical cross-sectional area (ACSA) of the thigh muscles, as determined with MRI, was 24% smaller in older compared to younger participants ( p