OBJECTIVE: To evaluate the contribution to peak bone mass of exercise, smoking, and calcium intake in adolescents and young adults. DESIGN: Prospective cohort study with end point measurement (bone mineral density) after 11 years' follow up for lifestyle. SETTING: Five university hospital clinics. SUBJECTS: 264 (153 females, 111 males) subjects aged 9 to 18 years at the beginning of the follow up and 20 to 29 years at the time of measurement of bone mineral density. MAIN OUTCOME MEASURE: Bone mineral density of lumbar spine and femoral neck by dual energy x ray absorptiometry; measures of physical activity and smoking and estimates of calcium intake repeated three times during follow up. RESULTS: In the groups with the lowest and highest levels of exercise the femoral bone mineral densities (adjusted for age and weight) were 0.918 and 0.988 g/cm2 for women (P = 0.015, analysis of covariance) and 0.943 and 1.042 g/cm2 for men (P = 0.005), respectively; at the lumbar spine the respective values were 1.045 and 1.131 (P = 0.005) for men. In men the femoral bone mineral densities (adjusted for age, weight, and exercise) were 1.022 and 0.923 g/cm2 for the groups with the lowest and highest values of smoking index (P = 0.054, analysis of covariance). In women the adjusted femoral bone mineral density increased by 4.7% together with increasing calcium intake (P = 0.089, analysis of covariance). In multiple regression analysis on bone mineral density of the femoral neck, weight, exercise, age, and smoking were independent predictors for men; with weight, exercise, and age for women. These predictors together explained 38% of the variance in bone mineral density in women and 46% in men. At the lumbar spine, weight, smoking, and exercise were predictors for men; and only weight for women. CONCLUSIONS: Regular exercise and not smoking is important in achieving maximal peak bone mass in adolescents and young adults.
OBJECTIVE: To evaluate the contribution to peak bone mass of exercise, smoking, and calcium intake in adolescents and young adults. DESIGN: Prospective cohort study with end point measurement (bone mineral density) after 11 years' follow up for lifestyle. SETTING: Five university hospital clinics. SUBJECTS: 264 (153 females, 111 males) subjects aged 9 to 18 years at the beginning of the follow up and 20 to 29 years at the time of measurement of bone mineral density. MAIN OUTCOME MEASURE: Bone mineral density of lumbar spine and femoral neck by dual energy x ray absorptiometry; measures of physical activity and smoking and estimates of calcium intake repeated three times during follow up. RESULTS: In the groups with the lowest and highest levels of exercise the femoral bone mineral densities (adjusted for age and weight) were 0.918 and 0.988 g/cm2 for women (P = 0.015, analysis of covariance) and 0.943 and 1.042 g/cm2 for men (P = 0.005), respectively; at the lumbar spine the respective values were 1.045 and 1.131 (P = 0.005) for men. In men the femoral bone mineral densities (adjusted for age, weight, and exercise) were 1.022 and 0.923 g/cm2 for the groups with the lowest and highest values of smoking index (P = 0.054, analysis of covariance). In women the adjusted femoral bone mineral density increased by 4.7% together with increasing calcium intake (P = 0.089, analysis of covariance). In multiple regression analysis on bone mineral density of the femoral neck, weight, exercise, age, and smoking were independent predictors for men; with weight, exercise, and age for women. These predictors together explained 38% of the variance in bone mineral density in women and 46% in men. At the lumbar spine, weight, smoking, and exercise were predictors for men; and only weight for women. CONCLUSIONS: Regular exercise and not smoking is important in achieving maximal peak bone mass in adolescents and young adults.
Authors: R B Sandler; C W Slemenda; R E LaPorte; J A Cauley; M M Schramm; M L Barresi; A M Kriska Journal: Am J Clin Nutr Date: 1985-08 Impact factor: 7.045
Authors: R Telama; J Viikari; I Välimäki; H Siren-Tiusanen; H K Akerblom; M Uhari; M Dahl; E Pesonen; P L Lähde; M Pietikäinen Journal: Acta Paediatr Scand Suppl Date: 1985