Effects of creatine supplementation and exercise training on fitness in men 55-75 yr old

• Published in: Journal of applied physiology (1985) 2003-08, Vol.95 (2), p.818-828
• Main Authors: Eijnde, Bert O, Van Leemputte, Marc, Goris, Marina, Labarque, Valery, Taes, Youri, Verbessem, Patricia, Vanhees, Luc, Ramaekers, Monique, Vanden Eynde, Bart, Van Schuylenbergh, Reinout, Dom, Rene, Richter, Erik A, Hespel, Peter
• Format: Article
• Language: English
• Subjects: Acids; Administration, Oral; Aged; Biological and medical sciences; Body Composition; Clinical trials; Creatine - administration & dosage; Creatine - blood; Creatine - metabolism; Creatine - urine; Dietary Supplements; Double-Blind Method; Exercise; Exercise Test; Follow-Up Studies; Fundamental and applied biological sciences. Psychology; Histocytochemistry; Humans; Isometric Contraction; Knee; Male; Men; Middle Aged; Muscle, Skeletal - metabolism; Muscle, Skeletal - physiology; Oxygen Consumption; Physical Education and Training; Physical Endurance; Physical Fitness; Time Factors; Vertebrates: body movement. Posture. Locomotion. Flight. Swimming. Physical exercise. Rest. Sports; Weight Lifting
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/japplphysiol.00891.2002

1 Exercise Physiology and Biomechanics Laboratory, Department of Kinesiology, and 3 Cardiorespiratory Rehabilitation Unit, Department of Rehabilitation Sciences, Faculty of Physical Education and Physiotherapy, KU Leuven, B-3001 Leuven; 2 Department of Clinical Chemistry, University of Gent, B-9000 Gent; 4 Neurology Unit, Faculty of Medicine, KU Leuven, B-3000 Leuven, Belgium; and 5 Institute of Exercise and Sports Sciences, University of Copenhagen, DK-2100 Copenhagen, Denmark Submitted 26 September 2002 ; accepted in final form 25 March 2003 effect of oral creatine supplementation (CR; 5 g/day) in conjunction with exercise training on physical fitness was investigated in men between 55 and 75 yr of age ( n = 46). A double-blind randomized placebo-controlled (PL) trial was performed over a 6-mo period. Furthermore, a subgroup ( n = 20) completed a 1-yr follow-up. The training program consisted of cardiorespiratory endurance training as well as moderate resistance training (2–3 sessions/wk). Endurance capacity was evaluated during a maximal incremental bicycle ergometer test, maximal isometric strength of the knee-extensor muscles was assessed by an isokinetic dynamometer, and body composition was assessed by hydrostatic weighing. Furthermore, in a subgroup (PL: n = 13; CR: n = 12) biopsies were taken from m. vastus lateralis to determine total creatine (TCr) content. In PL, 6 mo of training increased peak oxygen uptake rate (+16%; P < 0.05). Fat-free mass slightly increased (+0.3 kg; P < 0.05), whereas percent body fat slightly decreased (-1.2%; P < 0.05). The training intervention did not significantly change either maximal isometric strength or body weight. The responses were independent of CR. Still, compared with PL, TCr was increased by 5% in CR, and this increase was closely correlated with initial muscle creatine content ( r = -0.78; P < 0.05). After a 1-yr follow-up, muscle TCr was not higher in CR than in PL. Furthermore, the other measurements were not affected by CR. It is concluded that long-term creatine intake (5 g/day) in conjunction with exercise training does not beneficially impact physical fitness in men between 55 and 75 yr of age. elderly; muscle strength; endurance capacity Address for reprint requests and other correspondence: P. Hespel, Exercise Physiology and Biomechanics Laboratory, Faculty of Physical Education and Physiotherapy, Tervuursevest 101, B-3001 Leuven, Belgium.