Physical activity - Effects on Bone Health, Injury and Recovery

Abstract

This thesis is formed of four elements. The first addresses the effects of weight bearing physical activity on bone mineral density, it examines two populations of middle-aged women – a group of ex-elite athletes and one from the general population. It attempts to address the effects that lifelong adherence to weight-bearing exercise has on bone density.
The second element uses a monozygotic / dizygotic twin-model to determine to what extent bone mineral density is determined by genetics and how much by weight-bearing physical activity. This used a classic twin-model experiment to determine if monozygotic twins, who were highly discordant for exercise levels within their pairs, had different bone densities.
The third chapter deals with the epidemiology of musculoskeletal injuries in British Army recruit training and whether variables, measured at entry to training, could predict those at greatest risk of injury. This would have allowed the recruit trainers to stratify those at greatest risk of injury with a view to modifying training and adapting it to the capacity of the individual recruit and hence reducing injury rates. I used multiple logistic regression techniques and novel artificial intelligence, approaches.
The final study examines the optimal approach to rehabilitation of tibial stress fractures in a recruit training setting, by means of a randomised controlled trial (RCT). It also provided information on the natural history of the injury, its recovery and best diagnostic imaging techniques.
The common thread that links these chapters to form a logical thesis is the question: What is the effect of physical activity on the human skeleton, how do we mitigate against injury and, if this mitigation fails, how do we manage the consequences?

Date of Award	23 Jul 2025
Original language	English
Awarding Institution	University of Bath
Supervisor	James Bilzon (Supervisor) & Dario Cazzola (Supervisor)