Neuromuscular Function and Bone Geometry and Strength in Aging

Rantalainen, Timo Neuromuscular function and bone geometry and strength in aging Jyväskylä: University of Jyväskylä, 2010, 87 p. (Studies in Sport, Physical Education and Health ISSN 0356-1070; 148) ISBN 978-951-39-3959-5 (PDF), 978-951-39-3948-9 (nid.) Diss. Finnish summary Osteoporosis, falls and ensuing bone fractures cause individual suffering and economical burden. Pharmacological interventions are not cost effective for preventing these osteoporosis and aging related bone fractures, and therefore non-pharmacological interventions, such as exercise should be considered. The purpose of this thesis was to study the associations between body mass, neuromuscular performance (impulse and power in different types of jumps) and skeletal rigidity in both genders and in young and elderly subjects. The results of the studies suggest that tibial rigidity is related to maximal neuromuscular performance in young and elderly men and women. The association between bone rigidity and neuromuscular performance seemed to be moderate, but site and loading specific. Furthermore, neuromuscular performance adds to the predictive power of regression models beyond that of body mass. The difference in the bone rigidity to loading ratio between young and elderly individuals is bigger than one might expect from the delay in bone adaptation alone, indicating changes in skeletal mehcanosensitivity. However, even in the elderly, habitual explosive exercise seems to be associated with more rigid bones. Individual determinants of neuromuscular performance, such as specific tension, may contribute to increasing skeletal integrity and can be positively manipulated with exercises, which have also shown to be effective in fall prevention.