Bone and Muscle Development through Exercise and Training in Youth

Full Name: Panagiota Klentrou

Academic Affiliation: Department of Kinesiology, Faculty of Applied Health sciences, Brock University

Position: Professor

Abstract: The pubertal years are recognized as a critical period for optimum physical growth and physiological development. Accumulating a higher peak bone mass during childhood and adolescence is a key determinant of adult skeletal health and infers a protective advantage during the inevitable decline in bone mass that is associated with aging. Thus, any condition accelerating bone formation during this time will result in optimal skeletal development and may protect from osteoporotic fractures later in life. Recent attention has been given to gaining a greater understanding of how modifiable soft tissue components, including lean mass (LM) and fat mass (FM), influence bone properties during childhood and adolescence. According to our longitudinal data, during puberty, muscle strength is a significant determinant of bone strength. However, despite consensus regarding the association of LM with bone mass, there is limited research on how, when and what type of exercise provides optimum stimulus for muscle and bone development during growth. Our current research examines the effects of different exercise modalities and athletic training across pediatric populations. Our intervention studies have shown muscle function improvements in children with Cerebral Palsy, and that exercise training combined with dairy supplementation can have beneficial effects on bone through an increase in LM and a decrease in FM in obese adolescent girls. Recently, we have identified specific cellular pathways that drive the bone anabolic response to plyometric exercise in children while fluctuations in training volume during an Olympic year were found to have inflammatory and bone catabolic effects in elite female rowers. Overall, high impact exercise promotes bone accrual through muscle development in youth while chronic inflammation associated with intense training may negatively affect bone metabolism. Future research focuses on increasing the mechanistic understanding of the manner by which diverse physical stressors alter the integrity of bone and whether protein supplementation following exercise training can mitigate muscle damage and inflammation in pre- and post-pubertal athletes.