RT Journal Article
SR Electronic
T1 Age-related changes in the effects of strength training on lower leg muscles in healthy individuals measured using MRI
JF BMJ Open Sport & Exercise Medicine
JO BMJ OPEN SP EX MED
FD BMJ Publishing Group Ltd
SP e000249
DO 10.1136/bmjsem-2017-000249
VO 3
IS 1
A1 Maria Psatha
A1 Zhiqing Wu
A1 Fiona Gammie
A1 Aivaras Ratkevicius
A1 Henning Wackerhage
A1 Thomas W Redpath
A1 Fiona J Gilbert
A1 Judith R Meakin
A1 Richard M Aspden
YR 2017
UL http://bmjopensem.bmj.com/content/3/1/e000249.abstract
AB Background We previously measured the rate of regaining muscle strength during rehabilitation of lower leg muscles in patients following lower leg casting. Our primary aim in this study was to measure the rate of gain of strength in healthy individuals undergoing a similar training regime. Our secondary aim was to test the ability of MRI to provide a biomarker for muscle function.Methods Men and women were recruited in three age groups: 20–30, 50–65 and over 70 years. Their response to resistance training of the right lower leg twice a week for 8 weeks was monitored using a dynamometer and MRI of tibialis anterior, soleus and gastrocnemius muscles at 2 weekly intervals to measure muscle size (anatomical cross-sectional area (ACSA)) and quality (T2 relaxation). Forty-four volunteers completed the study.Results Baseline strength declined with age. Training had no effect in middle-aged females or in elderly men in dorsiflexion. Other groups significantly increased both plantarflexion and dorsiflexion strength at rates up to 5.5 N m week-1 in young females in plantarflexion and 1.25 N m week-1 in young males in dorsiflexion. No changes were observed in ACSA or T2 in any age group in any muscle.Conclusion Exercise training improves muscle strength in males at all ages except the elderly in dorsiflexion. Responses in females were less clear with variation across age and muscle groups. These results were not reflected in simple MRI measures that do not, therefore, provide a good biomarker for muscle atrophy or the efficacy of rehabilitation.