Motor unit firing rates and contractile properties in tibialis anterior of young and old men

• Published in: Journal of applied physiology (1985) 1999-08, Vol.87 (2), p.843-852
• Main Authors: Connelly, Denise M, Rice, Charles L, Roos, Martin R, Vandervoort, Anthony A
• Format: Article
• Language: English
• Subjects: Action Potentials - physiology; Adult; Age Factors; Aged; Aging; Biological and medical sciences; Electric Stimulation; Electromyography; Fundamental and applied biological sciences. Psychology; Humans; Males; Motor Neurons - physiology; Muscle Contraction - physiology; Muscle Fibers, Fast-Twitch - physiology; Muscle, Skeletal - physiology; Muscular system; Neurons; Space life sciences; Striated muscle. Tendons; Vertebrates: osteoarticular system, musculoskeletal system
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/jappl.1999.87.2.843

1  Center for Activity and Ageing, School of Kinesiology, Faculty of Health Sciences, 2  Department of Anatomy and Cell Biology, Faculty of Medicine, and 3  School of Physical Therapy, Faculty of Health Sciences, The University of Western Ontario, London, Ontario, Canada N6A 3K7 The effects of aging on motoneuron firing rates and muscle contractile properties were studied in tibialis anterior muscle by comparing results from six young (20.8 ± 0.8 yr) and six old men (82.0 ± 1.7 yr). For each subject, data were collected from repeated tests over a 2-wk period. Contractile tests included maximal voluntary contraction (MVC) with twitch interpolation and stimulated twitch contractions. The old men had 26% lower MVC torque ( P