title: The relationship between lower limb bone and muscle in military recruits, response to physical training, and influence of smoking status.
abstract: The relationship between bone and skeletal muscle mass may be affected by physical training. No studies have prospectively examined the bone and skeletal muscle responses to a short controlled exercise-training programme. We hypothesised that a short exercise-training period would affect muscle and bone mass together.
  
  
  METHODS
  Femoral bone and Rectus femoris Volumes (RFVOL) were determined by magnetic resonance imaging in 215 healthy army recruits, and bone mineral density (BMD) by Dual X-Ray Absorptiometry (DXA) and repeated after 12 weeks of regulated physical training.
  
  
  RESULTS
  Pre-training, RFVOL was smaller in smokers than non-smokers (100.9 ± 20.2 vs. 108.7 ± 24.5, p = 0.018; 96.2 ± 16.9 vs. 104.8 ± 21.3, p = 0.002 for dominant/non-dominant limbs), although increases in RFVOL with training (of 14.2 ± 14.5% and 13.2 ± 15.6%] respectively, p < 0.001) were independent of prior smoking status. Pre-training RFVOL was related to bone cortical volume (r(2) = 0.21 and 0.30, p < 0.001 for dominant and non-dominant legs), and specifically to periosteal (r(2) = 0.21 and 0.23, p < 0.001) volume. Pre-training dominant RFVOL was independently associated with Total Hip BMD (p < 0.001). Training-related increases in RFVOL and bone volumes were related. Whilst smokers demonstrated lower muscle mass than non-smokers, differences were abolished with training. Training-related increases in muscle mass were related to increases in periosteal bone volume in both dominant and non-dominant legs.
authors: 1] UCL Institute for Human Health and Performance, and NIHR University College London Hospitals Biomedical Research Centre, London, UK [2] Division of Respiratory and Critical Care Medicine, University Medicine Cluster, National University Health System, Singapore; Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors: Zudin
authors: Z
authors: Puthucheary
authors: English Institute of Sport, Manchester; and Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences,Northumbria University, Newcastle upon Tyne, UK.
authors: Mehdi
authors: M
authors: Kordi
authors: UCL Institute for Human Health and Performance, and NIHR University College London Hospitals Biomedical Research Centre, London, UK.
authors: Jai
authors: J
authors: Rawal
authors: Hippocrateon Private Hospital, Psaron 6-12, Engomi 2408, Nicosia, Cyprus.
authors: Kyriacos I
authors: KI
authors: Eleftheriou
authors: Scottish National Advanced Heart Failure Service, Golden Jubilee National Hospital, Cydebank, Glasgow, UK.
authors: John
authors: J
authors: Payne
authors: UCL Institute for Human Health and Performance, and NIHR University College London Hospitals Biomedical Research Centre, London, UK.
authors: Hugh E
authors: HE
authors: Montgomery
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D015444:Exercise; D005269:Femur / Q000033:anatomy & histology / Q000502:physiology*; D006801:Humans; D008889:Military Personnel; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000502:physiology*; D012907:Smoking; D055815:Young Adult