Comparison between menopause-related changes in bone mineral density of the lumbar spine and the proximal femur in Japanese female athletes: a long-term longitudinal study using dual-energy X-Ray absorptiometry

Changes in Hip Bone Mineral Density and Objectively Measured Physical Activity in Middle-Aged Women: A 6-Year Prospective Study

Purpose.

This study was conducted to determine if physical activity volume (PAv) and intensity (PAi) at baseline influence the likelihood of gaining hip bone mineral density (BMD) over 6 years.

Design and Sample.

In a prospective study, the sample was limited to 244 female nonsmokers, ages 35 to 45 years, and was approximately 90% white.

Setting and Measures.

PAv and PAi were measured in daily living conditions using accelerometers at baseline. BMD, measured by dual energy x-ray absorptiometry, and several confounding factors were measured in the lab.

Analysis.

On the basis of BMD change scores, participants were divided into three categories: BMD loss, minimal change, and BMD gain. Risk ratios were used to show the likelihood of BMD gains over time across different levels of PAv and PAi at baseline.

Results.

Women with higher PAv were more likely to show improvements in hip BMD from baseline to follow-up than their counterparts, as indicated by the Mantel-Haenszel chi-square (χ2mh = 6.1, p = .01). Women with high PAv were 2.50 times (95% CI, 1.19–5.24) more likely to experience hip BMD gains than women with low PAv, and women with moderate PAv were 2.20 times (95% CI, 1.08–4.45) more likely. PAi was not predictive of gains in hip BMD. Adjusting for potential confounders had little influence on the results.

Conclusions.

Middle-aged women with moderate or high levels of PAv are more likely to experience BMD gains at the hip over time compared with those who have low levels of PAv. However, PAi does not appear to influence the likelihood of gaining BMD at the hip over 6 years.

Effect of supervised and home exercise training on bone mineral density among breast cancer patients. A 12-month randomised controlled trial

The ability of combined step aerobic- and circuit-training to prevent bone loss after breast cancer treatments was related to skeletal site and patients' menopausal status. Among premenopausal breast cancer survivors, a 12-month exercise intervention completely prevented bone loss at the femoral neck, whereas no exercise effect was seen at lumbar spine or at neither site in postmenopausal women.

INTRODUCTION

The primary objective of this randomised clinical trial was to determine the preventive effect of supervised weight-bearing jumping exercises and circuit training on bone loss among breast cancer patients.

METHODS

Of 573 breast cancer survivors aged 35-68 years randomly allocated into exercise or control group after adjuvant treatments, 498 (87%) were included in the final analysis. The 12-month exercise intervention comprised weekly supervised step aerobic- and circuit-exercises and similar home training. Bone mineral density (BMD) at lumbar spine and femoral neck were measured by dual-energy X-ray absorptiometry. Physical performance was assessed by 2-km walking and figure-8 running tests, and the amount of physical activity was estimated in metabolic equivalent-hours/week.

RESULTS

In premenopausal women, bone loss at the femoral neck was prevented by exercise, the mean BMD changes being -0.2% among the trainees vs. -1.4% among the controls (p = 0.01). Lumbar bone loss could not be prevented (-1.9% vs. -2.2%). In postmenopausal women, no significant exercise-effect on BMD was found either at the lumbar spine (-1.6% vs. -2.1%) or femoral neck (-1.1% vs. -1.1%).

CONCLUSIONS

This 12-month aerobic jumping and circuit training intervention completely prevented femoral neck bone loss in premenopausal breast cancer patients, whereas no effect on BMD was seen in postmenopausal women.

The effects of Baduanjin qigong in the prevention of bone loss for middle-aged women

This study aimed to assess the efficacy of a 12-week Baduanjin qigong training program in preventing bone loss for middle-aged women. An experimental design was adopted, and subjects were assigned randomly into an experimental group (n = 44) and a control group (n = 43). The experimental group received a 12-week Baduanjin qigong training program, whereas the control group did not. Interleukin-6 (IL-6) and bone mineral density (BMD) were measured before and after the intervention. The results showed significant differences in IL-6 (t = -5.19, p < 0.000) and BMD (t = 1.99, p = 0.049) between the groups. Baduanjin reduced IL-6 and maintained BMD in the experimental group. In conclusion, this study demonstrates promising efficacy of Baduanjin in preventing bone loss commonly occurring in middle-aged women. Thus, Baduanjin is valuable for promoting and maintaining the health status of middle-aged women.

Changes in metacarpal bone mineral density with age and menopause using computed X-ray densitometry in Japanese women: Cross-sectional and longitudinal study

BACKGROUND

Bone mineral density (BMD) loss with age and menopause is widely accepted in elderly women. However, only a few studies have utilized a multiple regression model that includes physical characteristics to assess comprehensive lifetime changes in BMD.

OBJECTIVE

A prospective study was conducted to characterize the normal patterns in metacarpal BMD changes in Japanese women, and to assess the applicability of a fitting model using cross-sectional data compared with longitudinal variability.

SUBJECTS AND METHODS

The study consisted of 5422 healthy women in cross-sectional data and a 1-year follow-up of 359 women. The metacarpal BMD was measured by computed X-ray densitometry. Multiple linear and nonlinear regression analyses were performed in cross-sectional subjects. Nonparametric analysis was used to compare percentage rates of BMD changes between actual and estimated values.

RESULTS

The cross-sectional data showed that the best-fit equation was a nonlinear change model using the variables of age and height in premenopausal women, and years since menopause (YSM), age and height in postmenopausal women. The results of longitudinal data indicated the following. In premenopausal women, the actual BMD changes were greater in the 30-39 age group than the 20-29 age group and were less in the 50-59 group than the 40-49 group. The rates of annual change in BMD between the actual value and estimated value by change model were very similar. In postmenopausal women, the actual changes in BMD indicated that the rapid rate of reduction observed was over 3% at 0-5 YSM and 1.5% at 6-10 YSM, and thereafter showed a slower rate of decline at 11 YSM. The change model represented the trend of actual change in BMD for postmenopausal women, whereas the rates of estimated BMD loss underestimated the actual changes at 1-10 YSM.

CONCLUSION

The change model for premenopausal women using cross-sectional data is beneficial in evaluating the actual metacarpal BMD variability, whereas that for postmenopausal women is insufficient in estimating the longitudinal BMD variability.

Bone density and young athletic women. An update

High-school girls and collegiate women have tremendous opportunities to participate in athletic teams. Young girls are also playing in club and select teams at an early age and often, year-round. There are many benefits for participating in sport and physical activity on both the physical and mental health of girls and women. Decreased risk for heart disease and diabetes mellitus, along with improved self-esteem and body-image, were among the first reported benefits of regular physical activity. In addition, sport participation and physical activity is also associated with bone health. Athletes have a greater bone mineral density compared with non-active and physically active females. The increase in bone mass should reduce the risk of fragility fractures in later life. There appears to be a window of opportunity during the development of peak bone mass in which the bone is especially responsive to weight-bearing physical activity. Impact loading sports such as gymnastics, rugby or volleyball tend to produce a better overall osteogenic response than sports without impact loading such as cycling, rowing and swimming. Relatively little is known about the impact of retiring from athletics on bone density. It appears that former athletes continue to have a higher bone density than non-athletes; however, the rate of bone loss appears to be similar in the femoral neck. The positive impact of sports participation on bone mass can be tempered by nutritional and hormonal status. It is not known whether female athletes need additional calcium compared with the general female population. Due to the increased energy expenditure of exercise and/or the pressure to obtain an optimal training bodyweight, some female athletes may develop low energy availability or an eating disorder and subsequently amenorrhoea and a loss of bone mineral density. The three inter-related clinical disorders are referred to as the 'female athlete triad'. This article presents a review of the relationship between sports training and bone health, specifically bone mineral density, in young athletic women.

Physical training and hormone replacement therapy reduce the decrease in bone mineral density in perimenopausal women: a pilot study

The effects of physical training and hormone replacement therapy (HRT) on bone mineral density in perimenopausal women were studied. Sixty perimenopausal women were randomized to either physical training (n = 20), HRT (n = 20), or control group (n = 20). The study period was 18 months. Bone mineral density (BMD) in the femoral neck and lumbar spine was measured using dual-energy X-ray absorptiometry (DXA). DXA was performed before treatment and after 6 and 18 months. Blood samples for analysis of the bone markers U-deoxypyridinoline and osteocalcin were collected at the same time points. After 18 months, BMD in the spine had not decreased in either the training group or in the HRT group. In the control group, spine BMD had significantly decreased (p = 0.0014). U-Deoxypyridinoline and osteocalcin were increased significantly in the control group (p = 0.0198, p = 0.0295, respectively). No significant changes in bone marker levels were found in the training group or the HRT group. We found that both HRT and physical training can prevent loss of spine BMD in perimenopausal women over a period of 18 months. HRT remains a cornerstone in the treatment of vasomotor symptoms and preservation of BMD. However, HRT can only be used for limited periods of time due to the potential serious adverse effects. This study indicates a beneficial effect of physical activity on spine BMD in the perimenopausal period, and highlights its potential as an alternative to HRT during this period.

How many days per week should rats undergo running exercise to increase BMD?

The aim of the present study was to examine the effect of different frequencies of running exercise on increasing bone mineral density (BMD) and improving bone histomorphology at various sites of the skeleton (tibia, femur, and second lumbar vertebra) in young rats. Twenty-five female Wistar rats, 8 weeks old, were divided into five groups, of 5 animals each according to running load: control group, no running (A group); running load (RL), 4 days per week (d/w; B group); RL, 5 d/w (C group); RL, 6 d/w (D group); and RL, 7 d/w (E group). Rats ran on a treadmill at a speed of 15 m/min for 30 min per day over an 8-week period. The results indicated that the BMD of the tibia in the B, C, D, and E groups and that of the femur in the B and E groups increased significantly over that of the A group. However, the cortical BMD and trabecular BMD of the second lumbar vertebra did not change. In regard to bone histomorphometry of the tibia, a parameter of bone resorption (eroded surface/bone surface) was significantly lower in the B and D groups than in the A group. There were no differences in the parameters of bone formation. Tartaric acid-resistant acid phosphatase (TRACP) values were significantly lower in the B and C groups than in the A group. There were significant increases in body weight in the B group and in muscle weight in the C group. From the data obtained in this study, it was concluded that increases in BMD were obtained by a moderate running load at frequencies of 4 and 5 days per week.

Effect of alendronate and exercise on bone and physical performance of postmenopausal women: a randomized controlled trial

In this randomized, double-blind, placebo-controlled 12-month trial we evaluated effects of weight- bearing jumping exercise and oral alendronate, alone or in combination, on the mass and structure of bone, risk factors for falling (muscle strength and power, postural sway, and dynamic balance), and cardiorespiratory fitness in postmenopausal women. A total of 164 healthy, sedentary, early postmenopausal women were randomly assigned to one of four experimental groups: (1) 5 mg of alendronate daily plus progressive jumping exercise, (2) 5 mg alendronate, (3) placebo plus progressive jumping exercise, or (4) placebo. The primary endpoint was 12-month change in bone mass and geometry (measured with dual-energy X-ray absorptiometry and peripheral computed tomography at several axial and limb sites) and physical performance; the secondary endpoint was change in biochemical markers of bone turnover. The jumping exercise was conducted an average 1.6 +/- 0.9 (mean +/- SD) times a week. Alendronate daily was effective in increasing bone mass at the lumbar spine (alendronate vs placebo 3.5%; 95% CI, 2.2-4.9%) and femoral neck (1.3%; 95% CI, 0.2-2.4%) but did not affect other bone sites. Exercise alone had no effect on bone mass at the lumbar spine or femoral neck; it had neither an additive nor an interactive effect with alendronate at these bone sites. However, at the distal tibia the mean increase of 3.6% (0.3-7.1%) in the section modulus (that is, bone strength) and 3.7% (0.1-7.3%) increase in the ratio of cortical bone to total bone area were statistically significant in the exercise group compared to the nonexercise group, indicating exercise-induced thickening of the bone cortex. Bone turnover was reduced in alendronate groups only. Alendronate had no effect on physical performance while the jumping exercise improved leg extensor power, dynamic balance, and cardiorespiratory fitness. As conclusion Alendronate is effective in increasing bone mass at the lumbar spine and femoral neck, while exercise is effective in increasing the mechanical properties of bone at some of the most loaded bone sites, as well as improving the participants' muscular performance and dynamic balance. Together alendronate and exercise may effectively decrease the risk of osteoporotic fractures.

Hormone replacement therapy and menopause: a review of randomized, double-blind, placebo-controlled trials

Hormone replacement therapy (HRT) is frequently prescribed to healthy women to ameliorate menopausal symptoms. HRT is used long term (> or = 1 year) to prevent chronic disease in older women. The objective of this study was to review the benefits and risks of HRT and studies of menopause or HRT in Taiwan via a MEDLINE search. Recommendations are provided for future HRT research in Taiwan. Randomized, double-blind, placebo-controlled clinical trials are considered the gold standard of scientific evidence. A MEDLINE literature search (January 1966-July 2002) identified 23 papers on trials (> or = 1 year) that met the inclusion criteria. The results showed that various HRT regimens used for more than 1 year caused more harm than good in healthy menopausal women and that there was no benefit for women with coronary artery disease, Alzheimer's disease, hysterectomy, hysterosalpingo-oophorectomy, and ischemic stroke. None of this research was conducted in Taiwan. A MEDLINE search using the key words "estrogen replacement therapy and menopause in Taiwan" identified 16 studies. There was only one, short-term, HRT trial. No evidence suggested benefits from long-term HRT in menopausal women in Taiwan.

The Erlangen Fitness Osteoporosis Prevention Study: a controlled exercise trial in early postmenopausal women with low bone density-first-year results

OBJECTIVE

To investigate the effect of a 2-year vigorous, combined high-impact, strength, and endurance training program on bone mineral density (BMD) determined by dual-energy x-ray absorptiometry (DXA), quantitative computed tomography (QCT), and ultrasound in early postmenopausal women with osteopenia.

DESIGN

Nonrandomized controlled trial, reporting 1-year data.

SETTING

Community.

PARTICIPANTS

Early postmenopausal (1-8y postmenopausal) osteopenic women (DXA T score at lumbar spine or total hip between -1 and -2.5 standard deviations). The exercise group (n=59; mean age, 55.1+/-3.4y) and control group (n=41; mean age, 55.9+/-3.1y) were recruited from community registers.

INTERVENTION

Fourteen months of exercise training, with 2 joint sessions and 2 additional home training sessions. Exercise and control groups were supplemented individually with calcium and cholecalciferol up to 1500mg of calcium and 500IU of vitamin D per day.

MAIN OUTCOMES MEASURES

BMD at the lumbar spine and total hip measured by DXA, isometric maximum strength, and maximal oxygen consumption (VO2max) during a stepwise running test to exhaustion.

RESULTS

Bone density increased significantly at the lumbar spine for the exercise group (1.3%, P<.001) and decreased in the control group (-1.2%, P<.01). Differences at the total hip (-0.3%, not significant vs -0.8%, P<.05) and the femoral neck (-0.8%, P<.05 vs -1.8%, P<.001) were nonsignificant. Changes in isometric maximum strength were significant for each region (grip strength, trunk flexors and extensors, hip flexors, leg adductors and abductors, arm flexors and extensors) in the exercise group (11%-39%) compared with nonrelevant changes (-1.1% to 3.9%) in the control group. Between-group differences were significant (P<.01-.001) for all strength parameters. VO2max increased significantly by 11% (P<.001) in the exercise group but decreased in the control group by 4% (P<.05) while showing significant between-group differences.

CONCLUSION

High-intensity exercise training can have a positive influence on bone density in early postmenopausal osteopenic women.

Forearm bone mineral density by age in 7,620 men and women: the Tromsø study, a population-based study

Population-based studies of adult forearm bone mineral density (BMD) by age are scarce, and standardized reference values are lacking. In this cross-sectional study, men aged 55-74 years, women aged 50-74 years, and representative 5-10% samples of remaining age groups between 25 and 84 years living in Tromsø, Norway, were invited for forearm BMD measurement in 1994-1995. The authors measured 3,062 men and 4,558 women (response rate, 78%) by single x-ray absoptiometry at distal and ultradistal forearm sites. Up to age 50, the mean BMD difference was -0.1% per 1-year age group in both sexes. After age 50, the mean BMD difference per 1-year age group was -0.6% in men and -1.3% (distal) and -1.5% (ultradistal) in women. The BMD by age curve was linear for men throughout senescence, but women had a slope change to -0.7% (distal) and -0.8% (ultradistal) per 1-year age group from the 65- to 69-year age group. BMD levels and BMD by age association in the general population (n = 7,620) and in the population without bone-threatening diseases or medication (n = 5,179) were similar. Only longitudinal studies can clarify whether cohort effects or longitudinal BMD development patterns explain these cross-sectional results.

The side-to-side differences of bone mass at proximal femur in female rhythmic sports gymnasts

This cross-sectional study examined the side-to-side differences of the bone mineral density (BMD) at proximal femora in female rhythmic sports gymnasts (RSGs). The hypothesis on which the study is based is that gymnasts use a different leg in take-off (left leg) and in landing (right leg) and therefore differ in the loading for the left and right legs. The gymnasts made up two groups: the regular group, which consisted of 15 regular players who had trained for about 28 h/week, and the substitutes group, which consisted of 8 substitute players who had trained for about 12 h/week. The control group consisted of 10 nonathletic college women who had not participated in any kind of regular sports activity. BMD (g/cm2) was measured in three hip sites using the XR-26 dual-energy X-ray absorptiometer scanner. Muscle strength at knee extensors (EXT) and flexors (FLX) was examined using an isokinetic dynamometer (CYBEX6000), and the vertical ground reaction force was determined with a force platform during take-off and landing movements. In the regular players, the BMDs of the left leg were significantly higher than those of the right leg at the femoral necks, greater trochanters, and Ward's triangles (p < 0.01 to approximately 0.005). The side-to-side differences were 4.7 to approximately 9.6%. Regarding the strength parameters, the left side was greater than the right side significantly at EXT 60 degrees/s (p < 0.01), although the overall side-to-side difference was small. In the substitutes, the BMDs at the three sites mentioned above were also higher in the left leg than the right, but the side-to-side difference was statistically significant only at Ward's triangles (93%, p < 0.05). The side-to-side difference of strength was not significant. In the controls, there were small left-to-right differences of the BMDs, ranging from -1.8 to 0.5%, which was significantly lower than in the regular players at each site. The overall average strength measurements were larger in the right leg than in the left except at the 120 degrees/s. The side-to-side difference was statistically significant at EXT 30 degrees/s and 60 degrees/s (p < 0.05). The peak force was greater in take-off than in landing, and the unit time force during take-off was significantly greater than that during landing (p < 0.001). In conclusion, regarding the side-to-side difference of the BMD at proximal femora, our results demonstrate: that the left leg for take-off had higher measurements than the right leg for landing in both gymnasts' groups, which accounts for the vertical ground reaction force during take-off being greater than that during landing; that the difference in the regular players group was greater than that in the substitute group, which can be explained because the regular players practiced much more than the substitutes did; and that there was no difference in the control group.