Diet and Exercise on Bone

Summary

Deteriorating bone health across the age spectrum is a growing public health concern. Physical activity during the pubertal years has been shown to positively influence bone health in adulthood. In recent years, research has been undertaken on the effect of varying forms of activities on bone development in normally active children, as well as in young competing athletes. They have provided evidence of an overall significant improvement on bone health with physically active lifestyle. However, the optimal timing and type for habitual or intense exercise to bring about the most beneficial change in bone mineral and strength are still under investigation.

Studies on children participating in intense exercise regimes, such as artistic gymnastics, improve our understanding of the effect of high levels of mechanical loading on growing bone. However, the use of a relatively short follow-up and selection of narrow age groups in these studies do not allow full elucidation of development over the entire pubertal growth period. Timing and tempo of growth and maturation, which are known to considerably influence normal bone accrual, vary greatly amongst children.

Our principal aim was to investigate longitudinal differences in bone quantity (BMC, BMD) and bone quality (quantitative ultrasound) between females participating in high impact loading exercise and normally active controls.

Project Status : November 2008

The project data collection is now complete. Analysis of the samples for measurement of vitamin D status has been finished and analysis of these findings are underway.

The first part of the study has been published in the Journal of Bone and Mineral Research.

Dr Janna Nurmi-Lawton has successfully gained her PhD and won several awards including two Young Investigators Awards at the National Osteoporosis Society Conferences and the Student Award at the Nutrition Society Conference.

Further publication of the data is planned.

Project Objectives

The principal aim of this study was to investigate longitudinal differences in bone quantity (BMC, BMD) and bone quality (quantitative ultrasound) between females participating in high impact loading exercise and normally active controls.

The subject-population covered the entire pubertal growth period, hence the timing and tempo of both growth and maturation were carefully controlled.

The second aim was to assess the effect of heredity on bone health through mother-daughter comparison.

Results and Findings

Nurmi-Lawton JA., Baxter-Jones ADJ., Mirwald R., Bishop JA., Taylor P., Cooper C., New SA. Evidence of sustained skeletal benefits from impact-loading exercise in young adolescent females: a 3-year longitudinal study. Journal of Bone and Mineral Research 2004;19:314-322.

Nurmi-Lawton JA., Baxter-Jones ADJ., Mirwald R., Bishop JA., Taylor P., Cooper C., Fraser WD, Lanham-New SA. Altered bone turnover in adolescent females undertaking high-impact loading physical activity. 2008 (Submitted for publication).

Nurmi-Lawton JA, Baxter-Jones A, Taylor P, Cooper C, Bishop J, New S. Dietary balance in physically active and inactive girls. In: Nutritional Aspects of Osteoporosis. 2nd ed. Burckhardt P, Dawson-Hughes B, Heaney R (eds), pp. 431-438. Elsevier Science, USA, 2004.

Nurmi-Lawton JA, Fraser W, Baxter-Jones ADG, Bishop JA, Lowes L, Taylor P, Cooper C, New SA. Evidence of altered bone turnover in adolescent females undertaking high-impact loading exercise. Osteoporosis International 2003; 14(4): S14.

Nurmi-Lawton JA, Baxter-Jones A, Bishop JA, Taylor P, Cooper C, New SA. Skeletal calcium accretion and calcium intake in young females during puberty: data from a 3-year longitudinal study on bone health. Proceedings of the Nutrition Society 2003; 61: 111A.