Open AccessProperties of the vastus lateralis muscle in relation to age and physiological function in master cyclists aged 55–79 years
Author(s) -
Pollock Ross D.,
O'Brien Katie A.,
Daniels Lorna J.,
Nielsen Kathrine B.,
Rowlerson Anthea,
Duggal Niharika A.,
Lazarus Norman R.,
Lord Janet M.,
Philp Andrew,
Harridge Stephen D. R.
Publication year - 2018
Publication title -
aging cell
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.103
H-Index - 140
eISSN - 1474-9726
pISSN - 1474-9718
DOI - 10.1111/acel.12735
Subject(s) - vastus lateralis muscle , isometric exercise , muscle biopsy , biology , medicine , cardiorespiratory fitness , endocrinology , fast twitch muscle , vo2 max , muscle contraction , cohort , zoology , skeletal muscle , biopsy , anatomy , physiology , heart rate , blood pressure
Summary In this study, results are reported from the analyses of vastus lateralis muscle biopsy samples obtained from a subset ( n = 90) of 125 previously phenotyped, highly active male and female cyclists aged 55–79 years in regard to age. We then subsequently attempted to uncover associations between the findings in muscle and in vivo physiological functions. Muscle fibre type and composition ( ATP ase histochemistry), size (morphometry), capillary density (immunohistochemistry) and mitochondrial protein content (Western blot) in relation to age were determined in the biopsy specimens. Aside from an age‐related change in capillary density in males ( r = −.299; p = .02), no other parameter measured in the muscle samples showed an association with age. However, in males type I fibres and capillarity ( p < .05) were significantly associated with training volume, maximal oxygen uptake, oxygen uptake kinetics and ventilatory threshold. In females, the only association observed was between capillarity and training volume ( p < .05). In males, both type II fibre proportion and area ( p < .05) were associated with peak power during sprint cycling and with maximal rate of torque development during a maximal voluntary isometric contraction. Mitochondrial protein content was not associated with any cardiorespiratory parameter in either males or females ( p > .05). We conclude in this highly active cohort, selected to mitigate most of the effects of inactivity, that there is little evidence of age‐related changes in the properties of VL muscle across the age range studied. By contrast, some of these muscle characteristics were correlated with in vivo physiological indices.