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CONTEXT: A high peak bone mineral density (BMD; grams per square centimeter) could reduce the risk of osteoporosis related fractures later in life. OBJECTIVE: This 12-yr longitudinal study investigated whether a high BMD from previous high physical activity is maintained with reduced activity later in life. DESIGN: This was a longitudinal study. PARTICIPANTS: Three groups were investigated with a mean age of 17 yr at baseline; 51 athletes who stopped their active careers during follow-up (former athletes), 16 who were active throughout follow-up (active athletes), and 25 controls. Main Outcome Measures: BMD of the femoral neck, total body, and lumbar spine were examined five times during the 12-yr follow-up period. RESULTS: After adjustment for age, weight, and height, the former athletes were found to have higher BMD at all sites at every follow-up visit except the last one, when compared with controls (P < 0.05). The active athletes were found to have significantly higher BMD at all measured locations when compared with controls throughout the entire study (P < 0.05). From the first to the final follow-up visit, the former athletes were found to have lost more femoral neck BMD than both the active athletes (mean difference, 0.12 g/cm(2); P = 0.003) and controls (mean difference 0.08 g/cm(2); P = 0.02). CONCLUSION: This study suggests that BMD constantly adapts to the present physical activity levels in young men. Thus, increased BMD due to previous high physical activity may not prevent osteoporosis in later years.

Previous research has been inconclusive as to whether high peak bone mineral density (BMD, g/cm(2)) resulting from previous physical activity is retained with reduced activity later in life. The aim of this 12-year longitudinal study was to investigate the association between BMD loss and reduced physical activity (h/wk) at trabecular and cortical bone sites in men. Three groups with a mean age of 17 years at baseline were investigated: i) 51 athletes who discontinued their active careers during the follow-up period (former athletes), ii) 16 athletes who were active throughout the follow-up period (active athletes), and iii) 25 controls. BMD loss at the hip, spine, and pelvis (mainly trabecular bone) was compared to BMD loss at femur, humerus, and legs (mainly cortical bone) during a 12-year follow-up period. Across the total follow-up period in the total cohort, reduced physical activity was more strongly associated with changes at trabecular BMD sites, i.e. hip, spine, and pelvis (B=0.008-0.005 g/cm(2) per weekly hour physical activity (h), p<0.001), than at cortical bone sites, i.e. humerus, legs (B=0.002-0.003 g/cm(2)/h, p<0.05), and femur (p>0.05). At the final follow-up, former athletes showed higher BMD than controls only at the cortical bone sites of the humerus, legs, and femur (difference 0.05-0.10 g/cm(2), p<0.05). In conclusion, this study indicates that predominantly trabecular bone is lost with reduced physical activity levels in young men. Benefits were still evident at the more cortical sites eight years after the discontinuation of an active sports career.

The purpose of the present study was to investigate the influence of different types of weight bearing physical activity on bone gain during an active sports career and to identify any residual benefits in BMD after the active sports career. Beginning at 17 years of age, BMD was measured 5 times, during 12 years, at multiple sites in 19badminton players, 48 ice hockey players and 25 controls. Levels of vitamin D and fatty acids were also evaluated in relation to changes in BMD during the study. During the time the athletes were active, badminton players were found to have gained significantly more BMD in their femoral neck, humerus, and lumbar spine in comparison to control subjects (mean difference = 0.05-0.17 g/cm2, p < 0.05 for all), and significantly more in their legs compared to both ice hockey players and controls (mean difference = 0.03-0.05 g/cm2, p < 0.05). At final follow-up, badminton players had significantly higher BMD of the femoral neck, humerus, lumbar spine and legs (mean difference = 0.08-0.20 g/cm2, p<0.01 for all) than both ice hockey players and controls. Levels of vitamin D and fatty acids were not related to changes in BMD at any bone site (p > 0.05 for all). In summary, the present study suggests that badminton is a more osteogenic sport and therefore related to greater gains in BMD compared to ice hockey. These BMD benefits were partly sustained with reduced activity.

Background: Osteoporosis is a skeletal disease that affects one out of every two women and one out of every five men. The clinical significance of this disease lies in the associated increased risk of fractures that mainly affect the femoral neck, spine, and wrist. One of the strongest risk factors for low-energy fractures is low bone mineral density (BMD, g/cm2). The purpose of this study was to examine the relationship between BMD, self-perceived health, and lifestyle factors in a well-defined cohort of middle-aged men and women.

Methods: The Västerbotten Intervention Project (VIP) is a study that has been ongoing in Västerbotten since 1985. All people in Västerbotten who are 40, 50 and 60 years of age are offered a comprehensive health survey in which a questionnaire is completed and blood pressure and blood lipids are measured. BMD has been measured in the Sports Medicine Unit in Umeå since 1991. As of December 31, 2006, 4,333 women and 2,320 men had been evaluated.  Of these, 1,595 were examined as part of the VIP before their BMD was measured, and these subjects included in the present study.  

Results: The mean age of the investigated cohort was 57 years (range 30-74). After adjusting for age, weight, sex, and follow-up time, self-perceived health (Beta = 0.08, p<0.001), training[ED1]  (Beta = 0.11, p<0.001), snow shoveling (Beta = 0.07, p=0.001), and smoking more than 15 cigarettes per day (Beta =- 0.05, p=0.04) were found to be related to femoral neck BMD. Only self-perceived health, age, and weight were found to be related to spine BMD. Self-perceived health was found to be related to some of the lifestyle factors that were significantly related to BMD, such as training (r = 0.14, p <0.001) and snow shoveling (Beta = 0.15, p <0.001).

Conclusion: In this cohort study, several lifestyle factors related to self-perceived health were also found to be related to bone mineral density in a well-defined cohort of middle-aged men and women.