Intensity of exercise is associated with bone density change in premenopausal women
High-impact exercise is known to be beneficial for bones. However, the optimal amount of exercise is not known. The aim of the present study was to evaluate the association between the intensity of exercise and bone mineral density (BMD).
We performed a 12-month population–based trial with 120 women (aged 35–40 years) randomly assigned to an exercise group or to a control group. The intensity of the physical activity of 64 women was assessed with an accelerometer–based body movement monitor. The daily activity was analyzed at five acceleration levels (0.3–1.0 g, 1.1–2.4 g, 2.5–3.8 g, 3.9–5.3 g, and 5.4–9.2 g). BMD was measured at the hip, spine (L1–L4), and radius by dual-energy x–ray absorptiometry. The calcaneus was measured using quantitative ultrasound.
Physical activity that induced acceleration levels exceeding 3.9 g correlated positively with the BMD change in the hip area (p<0.05–0.001). L1 BMD change correlated positively with activity exceeding 5.4 g (p<0.05) and calcaneal speed of sound with the level of 1.1–2.4 g (p< 0.05). Baseline BMD was negatively associated with the BMD change at the hip.
The intensity of exercise, measured as the acceleration level of physical activity, was significantly correlated with BMD changes. Bone stimulation is reached during normal physical exercise in healthy premenopausal women. In the hip area, the threshold level for improving BMD is less than 100 accelerations per day at levels exceeding 3.9 g.
KeywordsAccelerometry Body movement monitor High-impact exercise Osteoporosis Physical activity Prevention
The authors would like to express their special thanks to Minna Tervo, the physiotherapist in our study team, for her dedication and hard work in supervising the training and testing of our subjects. We thank Pentti Nieminen, Ph.D., for statistical advice, and the staff of the Department of Sports Medicine at Oulu Deaconess Institute for their assistance. Lastly, we gratefully acknowledge the dedicated women who participated in this study. The study was supported by the National Technology Agency of Finland; Newtest Ltd., Oulu, Finland; CCC Group, Oulunsalo, Finland; Fastrax Ltd., Vantaa, Finland; the Juho Vainio Foundation, Helsinki, Finland; Instrumentarium Research Foundation, Helsinki, Finland; the Research Foundation of the Institutes of Sports, Helsinki, Finland; and the Finnish Foundation for Sports Research, Helsinki, Finland. The companies have no control on the conduct or the publication of the study. J. Leppäluoto, T. Jämsä, and R. Korpelainen have a patent application with Newtest Ltd.
- 1.Wolff J (1892) Das Gesetz der Transformation der Knochen. Translation by Maquet P, Furlong R (1986) The law of bone remodelling. Springer, Berlin Heidelberg New YorkGoogle Scholar
- 5.Greendale GA, Barrett–Connor E, Edelstein S, Ingles S, Haile R (1995) Lifetime leisure exercise and osteoporosis. The Rancho Bernardo study. Am J Epidemiol 141:951–959Google Scholar
- 6.Campbell AJ, Robertson MC, Gardner MM, Norton RN, Tilyard MW, Buchner DM (1997) Randomised controlled trial of a general practice programme of home based exercise to prevent falls in elderly women. BMJ 315:1065–69Google Scholar
- 9.Wolff I, van Croonenborg JJ, Kemper HC, Kostense PJ, Twisk JW (1999) The effect of exercise training programs on bone mass: a meta-analysis of published controlled trials in pre- and postmenopausal women. Osteoporos Int 9:1–12Google Scholar
- 10.Wallace BA, Cumming RG (2000) Systematic review of randomized trials of the effect of exercise on bone mass in pre- and postmenopausal women. Calcif Tissue Int 67:10–18Google Scholar
- 11.Kontulainen S, Heinonen A, Kannus P, Pasanen M, Sievänen H, Vuori I (2004) Former exercisers of an 18-month intervention display residual aBMD benefits compared with control women 3.5 years post-intervention: a follow-up of a randomized controlled high-impact trial. Osteoporos Int 15:248–251CrossRefPubMedGoogle Scholar
- 13.Bassey EJ, Rothwell MC, Littlewood JJ, Pye DW (1998) Pre- and postmenopausal women have different bone mineral density responses to the same high-impact exercise. J Bone Miner Res 13:1805–1813Google Scholar
- 15.Kemmler W, Lauber D, Weineck J, Hensen J, Kalender W, Engelke K (2004) Benefits of 2 years of intense exercise on bone density, physical fitness, and blood lipids in early postmenopausal osteopenic women: results of the Erlangen Fitness Osteoporosis Prevention Study (EFOPS). Arch Intern Med 164:1084–1091CrossRefPubMedGoogle Scholar
- 16.Servais SB, Webster JG, Montoye HG (1984) Estmating human energy expenditure using an accelerometer device. J Clin Eng 9:159–171Google Scholar
- 18.Eston RG, Rowlands AV, Ingledew DK (1998) Validity of heart rate, pedometry, and accelerometry for predicting the energy cost of children’s activities. J Appl Physiol 84:362–371Google Scholar
- 19.Menz HB, Lord SR, Fitzpatrick RC (2003) Acceleration patterns of the head and pelvis when walking on level and irregular surfaces. Gait Posture 18:35–46Google Scholar
- 20.Janz KF, Rao S, Baumann H, Schultz JL (2003) Measuring children’s vertical ground reaction forces with accelerometry during walking, running, and jumping: the Iowa bone development study. Pediatr Exerc Sci 15:34–43Google Scholar
- 24.Tuppurainen M, Kroger H, Saarikoski S, Honkanen R, Alhava E (1995) The effect of gynecological risk factors on lumbar and femoral bone mineral density in peri- and postmenopausal women. Maturitas 21:137–145Google Scholar
- 25.Vihriälä E, Saarimaa R, Myllylä R, Jämsä T (2003) A device for long term monitoring of impact loading on the hip. Mol Quantum Acoustics 24:211–224Google Scholar
- 26.Vihriälä E, Oksa J, Karkulehto J, Korpelainen R, Myllylä R, Jämsä T (2004) Reliability of an accelerometry in the assessment of body movements. Technol Health Care 12:122–124Google Scholar
- 30.Kavanagh JJ, Barrett RS, Morrison S (2004) Upper body accelerations during walking in healthy young and elderly men. Gait Posture 20:291–298Google Scholar
- 31.Auvinet B, Berrut G, Touzard C, Moutel L, Collet N, Chaleil D, Barrey E (2002) Reference data for normal subjects obtained with an accelerometric device. Gait Posture 16:124–134Google Scholar
- 33.Auvinet B, Gloria E, Renault G, Barrey E (2002) Runner’s stride analysis: comparison of kinematic and kinetic analyses under field conditiond. Sci Sport 17:92–94Google Scholar
- 34.Bussmann JB, Damen L, Stam HJ (2000) Analysis and decomposition of signals obtained by thigh-fixed uni-axial accelerometry during normal walking. Med Biol Eng Comput 38:632–638Google Scholar
- 35.Auvinet B, Chaleil D, Barrey E (1999) Accelerometric gait analysis for use in hospital outpatients. Revue du Rhumatisme [English edn] 66:389–397Google Scholar
- 39.Turner CH, Owan I, Takano Y (1995) Mechanotransduction in bone: role of strain rate. Am J Physiol 269:E438–E442Google Scholar
- 41.Judex S, Zernicke RF (2000) High-impact exercise and growing bone: relation between high strain rates and enhanced bone formation. J Appl Physiol 88:2183–2191Google Scholar
- 43.Umemura Y, Sogo N, Honda A (2002) Effects of intervals between jumps or bouts on osteogenic response to loading. J Appl Physiol 93:1345–1348Google Scholar