Heather McKay, PhD, is an associate professor in the School of Human Kinetics at the University of British Columbia in Vancouver, Canada. She also is adjunct professor in the university's department of medicine and an associate in its Institute of Health Promotion Research. For many years, she has conducted research related to the bone health of women and girls and was involved in one of the earliest studies of amenorrhea in collegiate runners. Dr. McKay was key investigator in the University of Saskatchewan Pediatric Bone Mineral Accrual Study.

Pekka Kannus, MD, PhD, is chief physician and head of the Accident and Trauma Research Center at the UKK Institute in Tampere, Finland. He also is a professor of injury prevention at the University of Tampere and an associate professor of sports medicine at the University of Jyväskylä in Finland. His scientific work has focused on basic and applied research of the musculoskeletal system of the human body. His primary interest is in bone research and prevention of osteoporotic fractures.

Don Bailey, PhD, is a professor at the University of Saskatchewan in Saskatoon, Canada, and the University of Queensland in Brisbane, Australia. During his scientific career, he has studied child growth and development and the relationship between bone mineral accrual and physical activity in the growing years. He directed the landmark Saskatchewan Growth Study, a 10-year investigation of growth and physical fitness in school-age children.

John Wark, MD, PhD, is a professor of medicine at the University of Melbourne in Australia. He is head of the Bone and Mineral Service at the Royal Melbourne Hospital and the director of the Centre of Osteoporosis and Bone Studies at the same leading teaching hospital campus. As both a specialist in endocrinology and an internationally recognized authority on bone metabolism, Dr. Wark covers a wide range of issues regarding bone, nutrition, and physical activity. He was the principal investigator in the first controlled trial of physical activity intervention in schoolgirls.

Kim Bennell, PT, PhD, is an associate professor in the school of physiotherapy and head of the Centre for Sports Medicine Research and Education at the University of Melbourne in Australia. She also is a director of a private physiotherapy clinic that specializes in exercise prescription in the prevention and treatment of osteoporosis. Dr. Bennell earned her reputation in the bone field for her pivotal stress fracture research and work in physical activity and bone mineral in active people. She is the author of the first prospective study of the risk factors for stress fractures. Dr. Bennell is currently undertaking National Health and Medical Research Council funded research on the effect of ballet training in young girls.