Grant: Doctoral Award - Frederick Banting and Charles Best Canada Graduate Scholarships

Osteoporosis is a complex disease in which bones become fragile and are more likely to break. Approximately 2 million Canadians live with osteoporosis, costing our health care system $3.9 billion each year. We do not have a complete understanding of what makes a bone strong; therefore, we are unable to predict if someone is going to suffer a fracture when they fall. Muscles and bones can gain strength from physical activity because they both increase in cross sectional size (girth) and density. The small architecture inside the bone can also increase bone strength, but we do not know if more physical activity or bigger, denser muscles can affect this aspect of bone strength. The role of physical activity, muscle size, strength, and density on bone structure is poorly understood in both men and women, especially in older adults. Our study will examine the roles of physical activity and muscle properties in bone strength in 66 young adult men and women around the age of 30, as well as 147 healthy men and women around 75 years of age. Muscle and bone properties will be measured using state-of-the-art high resolution imaging technologies, mechanical engineering computer models, and various movement tests often used by physical therapists. Physical activity will be assessed by having participants wear a small accelerometer and answer questions about their regular activity. We will focus our predictions about bone micro-architecture on the wrist, a common site for fall related fractures, and the ankle, a weight-bearing bone site. This work will provide new evidence about physical activity and muscle-bone health in both men and women at different ages and will contribute in making better tools for predicting bone strength and risk of fractures. Importantly, these results will guide new fracture prevention and rehabilitation programs to help improve the quality of life and physical functioning of Canadians who suffer with osteoporosis.