Chris J McNeil1, Charles L Rice. 1. Canadian Centre for Activity and Aging, School of Kinesiology, Faculty of Health Sciences, Arthur and Sonia Labatt Health Sciences Building, The University of Western Ontario, London, Ontario, Canada.
Abstract
BACKGROUND: Muscle power is more relevant to the activities of daily living than is isometric strength. However, dynamic contractions have received little attention as they relate to the effect of age on muscle fatigue, particularly in very old persons. Thus, the purpose of this study was to investigate fatigue of the dorsiflexors during a velocity-dependent (isotonic) power task in 12 young (26 years), 12 old (64 years), and 12 very old (84 years) men. METHODS: The fatigue protocol involved 25 maximal (as fast as possible) contractions at a load of 20% maximum isometric strength through a 25 degrees range of motion. Electromyographic signals of the tibialis anterior and soleus muscles were recorded to assess agonist activation and antagonist coactivation, respectively. RESULTS: Fatigability increased progressively with age as muscle power decreased by 13% in young men, 19% in old men, and 24% in very old men. In contrast, agonist activation and antagonist coactivation were unaffected by age. During the fatigue protocol, agonist activity decreased by 3%, 5%, and 4%, whereas antagonist activity increased by 11%, 13%, and 13% in young, old, and very old men, respectively. CONCLUSION: These results demonstrate that older adults are more fatigable than young adults during a velocity-dependent power task. This finding is in contrast to the majority of fatigue data previously reported from less functionally relevant isometric or isokinetic tasks.
BACKGROUND: Muscle power is more relevant to the activities of daily living than is isometric strength. However, dynamic contractions have received little attention as they relate to the effect of age on muscle fatigue, particularly in very old persons. Thus, the purpose of this study was to investigate fatigue of the dorsiflexors during a velocity-dependent (isotonic) power task in 12 young (26 years), 12 old (64 years), and 12 very old (84 years) men. METHODS: The fatigue protocol involved 25 maximal (as fast as possible) contractions at a load of 20% maximum isometric strength through a 25 degrees range of motion. Electromyographic signals of the tibialis anterior and soleus muscles were recorded to assess agonist activation and antagonist coactivation, respectively. RESULTS: Fatigability increased progressively with age as muscle power decreased by 13% in young men, 19% in old men, and 24% in very old men. In contrast, agonist activation and antagonist coactivation were unaffected by age. During the fatigue protocol, agonist activity decreased by 3%, 5%, and 4%, whereas antagonist activity increased by 11%, 13%, and 13% in young, old, and very old men, respectively. CONCLUSION: These results demonstrate that older adults are more fatigable than young adults during a velocity-dependent power task. This finding is in contrast to the majority of fatigue data previously reported from less functionally relevant isometric or isokinetic tasks.
Authors: Neil B Alexander; George E Taffet; Frances McFarland Horne; Basil A Eldadah; Luigi Ferrucci; Susan Nayfield; Stephanie Studenski Journal: J Am Geriatr Soc Date: 2010-05 Impact factor: 5.562
Authors: Gary R Hunter; C Scott Bickel; Pedro Del Corral; Nuala M Byrne; Andrew P Hills; D Enette Larson-Meyer; Marcas M Bamman; Bradley R Newcomer Journal: Eur J Appl Physiol Date: 2010-10-23 Impact factor: 3.078
Authors: Stephen E Alway; Jean L McCrory; Kalen Kearcher; Austen Vickers; Benjamin Frear; Diana L Gilleland; Daniel E Bonner; James M Thomas; David A Donley; Mathew W Lively; Junaith S Mohamed Journal: J Gerontol A Biol Sci Med Sci Date: 2017-11-09 Impact factor: 6.053
Authors: Sonja Vestergaard; Susan G Nayfield; Kushang V Patel; Basil Eldadah; Matteo Cesari; Luigi Ferrucci; Graziano Ceresini; Jack M Guralnik Journal: J Gerontol A Biol Sci Med Sci Date: 2009-01-27 Impact factor: 6.053
Authors: Laura Kyguoliene; Albertas Skurvydas; Nerijus Eimantas; Neringa Baranauskiene; Rasa Steponaviciute; Laura Daniuseviciute; Henrikas Paulauskas; Margarita Cernych; Marius Brazaitis Journal: Exp Brain Res Date: 2018-05-12 Impact factor: 1.972