This study examined whether participation in high-impact sports during adolescence and adulthood contributes to bone health in males aged 40 years. Data were analyzed on 154 Belgian men aged 13 years at study onset in 1969 and aged 40 years at the end of the 27-year follow-up. In a second analysis, subjects were divided into three groups according to their sports participation history: participation during adolescence and adulthood in high-impact sports (HH; n=18), participation during adolescence in high-impact sports and during adulthood in nonimpact sports or no sports (HN; n=15), and participation during adolescence and adulthood in nonimpact sports or no sports (NN; n=14). Body mass and impact loading during adulthood were significant predictors of total body bone mineral density (BMD) and lumbar spine BMD. Analysis of variance revealed significant differences for lumbar spine BMD between the HH (1.12 g/cm2) group and the HN (1.01 g/cm2) and NN (0.99 g/cm2) groups (F=5.07, p=0.01). Total body BMD was also higher in the HH group at age 40 years, but not significantly (F=3.17, p=0.0515). Covariance analyses for total body BMD and lumbar spine BMD, with body mass and time spent participating in sports as covariates, confirmed these results. Continued participation in impact sports is beneficial for the skeletal health of males aged 40 years.

The aim of this study was to determine whether high-impact exercises have an osteogenic effect in 21 prepubertal female monozygotic twins aged 8.7 (SD 0.7) years. Bone mineral density (aBMD), bone mineral content (BMC), bone area, and body composition were derived from DXA. Skeletal maturity was assessed by the Tanner-Whitehouse technique. Anthropometric dimensions (28 dimensions) were measured and also used to derive adiposity and muscularity indices, and information about physical activity was obtained by questionnaire. These measurements were taken before and after the exercise period. The exercise program consisted of high-impact exercises. During 9 months, one girl of each twin pair performed the exercises 3 times a week under supervision of a teacher while their sisters served as control group. At baseline there were no differences between the groups. After 9 months, exercisers (Ex) and controls (Con) had similar increases in height and weight. Significant lower adiposity was observed in the exercise group vs the control group. None of the bone indices differed significantly between the two groups. When the analyses were done for a subgroup of twin pairs (n = 12) who did not participate in high-impact sports during their leisure time, significant differences were obtained for aBMD and BMC of the proximal femur in favor of the exercise group. These results indicate that for prepubertal girls who are not involved in sport activities or who are only involved in low-impact sport activities this exercise program has an osteogenic effect on the proximal femur, but for girls who are already involved in high-impact sports this protocol does not have any additional effect on the bone status.

The association between bone mass, body structure, and body composition was explored in 156 men, 40 years of AGE. Bone mineral density (total body, lumbar spine, left arm, and left leg) was obtained by dual-energy X-ray absorptiometry (DXA; Hologic QDR 4500A). Body structure was determined from a battery of anthropometric dimensions with a principal components analysis. Body composition was estimated with DXA. From the 24 anthropometric dimensions, three components were extracted and identified as muscle, fat, and skeletal length. Significant correlations between the muscle component and all BMD measurements (r = 0.28-0.44) were obtained. Except for BMD of the left arm, which correlated significantly, but negatively, with the fat component (r = -0.16), no significant relations were found between the fat component and BMD. There were significant correlations between lean mass, fat mass, and BMD measurements. The correlations were higher between lean mass and BMD (r = 0.22-0.44) than between fat mass and BMD (r = 0.08-0.24). The multiple regression analysis revealed that except for BMD of the left arm only lean mass or the muscle component, and not fat mass or the fat component, were independent predictors of BMD. It is concluded that the principal anthropometric determinant of BMD in middle-aged men is lean mass or muscle.

In premenarcheal girls, bone is partly determined by mass, with lean mass the most important predictor at the femoral sites. In postmenopausal women, lean mass is an important determinant of bone mineral content (BMC) and BMD, but changes in BMD are related to changes in fat. The relation between strength and BMD is mainly attributable to the relation between lean mass and BMD. The contributory effects of soft tissue to bone change over different life periods.

Objective: The purpose of the present study was to analyse the lipid profile in men and women differentiated according to energy expenditure during sports participation (EE SPORT ), energy expenditure during active leisure time (EE ALT ) and overall energy expenditure (EE TOTAL ). Design: The subjects were grouped by sex, age, EE SPORT , EE ALT and EE TOTAL . Group differences were analysed using analyses of covariance with BMI and alcohol consumption as covariates. Setting: Physical activity was assessed using the Flemish Physical Activity Computerised Questionnaire. Fasting blood samples were taken to measure total cholesterol (TC), TAG, HDL-cholesterol (HDL-C), LDL-cholesterol (LDL-C) and the ratio TC:HDL-C. Subjects: The study sample consisted of 1170 Flemish men and women between 18 and 75 years of age. Results: Differences in lipid profile were observed in the younger age group (,45 years), all in favour of the most active group. More specifically, when differentiating by EE ALT and EE TOTAL , men had a healthier lipid profile for TAG, HDL-C and TC:HDL-C. Differentiation according to EE SPORT revealed the same significant results except for TAG. In women significant results for HDL-C, LDL-C and TC:HDL-C were found when differentiated by EE SPORT . Conclusions: Men and women ,45 years of age with higher levels of energy expenditure due to sport show a better lipid profile than their sedentary counterparts. When differentiating subjects according to energy expenditure during active leisure time or overall energy expenditure, only in men was a healthier lipid profile observed in favour of the most active subjects.