Effect of office-based brief high-impact exercise on bone mineral density in healthy premenopausal women: the Sendai Bone Health Concept Study

Effects of kinect-based virtual reality training on bone mineral density and fracture risk in postmenopausal women with osteopenia: a randomized controlled trial

Osteopenia is a condition characterized by low bone mineral density (BMD) that increases fracture risk, particularly among postmenopausal women (PMW). This study aimed to determine the effects of Kinect-based VRT on BMD and fracture risk in PMW with osteopenia. The study was a prospective, two-arm, parallel-design, randomized controlled trial. The study enrolled 52 participants, 26 randomly assigned to each group. In the experimental group, Kinect-based VRT was provided thrice weekly for 24 weeks for 45 min/session. Both groups were instructed to engage in a daily 30-min walk outdoors. The fracture risk assessment tool (FRAX) was used to calculate fracture risk, and dual-energy X-ray absorptiometry was used to measure lumbar spine and femur neck BMD. Both variables were assessed at baseline and 24 weeks afterwards. After 24 weeks of Kinect-based VRT, the experimental group showed significant BMD increases in the right and left femoral necks and lumbar spine (p value < 0.001). In the control group, the BMD at the right and left femoral necks showed fewer significant changes (p value < 0.022 and 0.004, respectively). In the control group, lumbar spine BMD did not change (p = 0.57). The experimental group showed significantly lower FRAX scores for hip fracture prediction (HFP) and hip prediction of major osteoporotic (HPMO) at both femoral necks (p value < 0.001) than the control group (p = 0.05 and p = 0.01, respectively), but no significant change at the left femoral neck for HFP (p = 0.66) or HPMO (p = 0.26). These findings indicate that a Kinect-based VRT intervention resulted in significantly increased BMD and a reduced fracture risk, as predicted by HFP and HPMO measurements. These improvements were more pronounced in the experimental group than in the control group. Thus, Kinect-based VRT may be utilized as an effective intervention to improve BMD and reduce fracture risk in postmenopausal women with osteopenia.

Skeletal site-specific effects of jump training on bone mineral density in adults: a systematic review and meta-analysis

Preserving or preventing declines in bone mineral density (BMD) is imperative. As jumping is a high-impact bone-loading action, this meta-analysis evaluated the efficacy of jump training to improve BMD and bone turnover relative to non-jumping controls in men and women > 18 years, following Preferred Reported Items for Systematic Reviews and Meta-Analysis guidelines. PubMed and COCHRANE Library databases were searched until February 2022. Fifteen articles (19 jumping-trials) met the predetermined search criteria. Eighteen trials were included for BMD data (n = 666 participants). There was a significant small-moderate effect of jumping on femoral neck BMD (%mean difference: 95%CI, +1.50%: 0.83%; 2.17%, p < 0.0001), that remained significant after sub-analysis by age for both younger (+1.81%: 0.98%; 2.65%) and older adults (+1.03%: 0.02%; 2.03%). BMD of total hip (+1.26%: 0.56%; 1.96% vs + 0.06%: -0.96%; 1.08%), and trochanter (+0.84%: 0.20%; 1.48% vs -0.16%: -1.08%; 0.76%) increased significantly with jump training only in younger adults and non-significantly at the lumbar spine (+0.84%: -0.02%; 1.7% vs -0.09%: -0.96%; 0.77%) only in younger but not older adults, respectively. The BMD response to jump training appears to be site-specific, with the highest sensitivity at the femoral neck. No dose-response effect suggests moderate certainty of a gain in femoral neck BMD when performing the median jump-load of 50 jumps four times weekly.

High-impact jumping mitigates the short-term effects of low energy availability on bone resorption but not formation in regularly menstruating females: A randomized control trial

Low energy availability (LEA) is prevalent in active individuals and negatively impacts bone turnover in young females. High-impact exercise can promote bone health in an energy efficient manner and may benefit bone during periods of LEA. Nineteen regularly menstruating females (aged 18-31 years) participated in two three-day conditions providing 15 (LEA) and 45 kcals kg fat-free mass-1  day-1 (BAL) of energy availability, each beginning 3 ± 1 days following the self-reported onset of menses. Participants either did (LEA+J, n = 10) or did not (LEA, n = 9) perform 20 high-impact jumps twice per day during LEA, with P1NP, β-CTx (circulating biomarkers of bone formation and resorption, respectively) and other markers of LEA measured pre and post in a resting and fasted state. Data are presented as estimated marginal mean ± 95% CI. P1NP was significantly reduced in LEA (71.8 ± 6.1-60.4 ± 6.2 ng mL-1 , p < 0.001, d = 2.36) and LEA+J (93.9 ± 13.4-85.2 ± 12.3 ng mL-1 , p < 0.001, d = 1.66), and these effects were not significantly different (time by condition interaction: p = 0.269). β-CTx was significantly increased in LEA (0.39 ± 0.09-0.46 ± 0.10 ng mL-1 , p = 0.002, d = 1.11) but not in LEA+J (0.65 ± 0.08-0.65 ± 0.08 ng mL-1 , p > 0.999, d = 0.19), and these effects were significantly different (time by condition interaction: p = 0.007). Morning basal bone formation rate is reduced following 3 days LEA, induced via dietary restriction, with or without high-impact jumping in regularly menstruating young females. However, high-impact jumping can prevent an increase in morning basal bone resorption rate and may benefit long-term bone health in individuals repeatedly exposed to such bouts.

Factors predicting long-term physical activity of breast cancer survivors. 5-year-follow-up of the BREX exercise intervention study

BACKGROUND

The benefits of exercise training are well documented among breast cancer (BC) survivors. Patients decrease their physical activity during treatment, and many fail to regain their previous exercise levels. There is therefore a need to define factors supporting long-term physical activity behavior in this patient group, to target supporting interventions aimed at preventing the decline in physical activity (PA).

AIM

The aim of this study was to determine physical and psychosocial factors explaining long-term physical activity after the adjuvant treatments in BC survivors.

METHODS

Four-hundred forty-six BC survivors followed for 5-years within a randomized exercise trial participated. Factors explaining (1) physical activity after the adjuvant treatments and (2) changes in physical activity in long-term were analyzed using linear regression models and general estimating equation models. Pretreatment leisure-time physical activity (LTPA), demographic, and treatment factors, physical fitness, and quality of life (Qol) at baseline were independent factors.

RESULTS

Exercise levels increased during the first year, and thereafter remained mostly stable. Higher LTPA, higher fitness level, better Qol and older age at baseline were associated with higher physical activity level after adjuvant treatments (p < .001) in multivariate analysis. Higher levels of fatigue (p < .008) and better emotional functioning (p = .017) at baseline were the main factors associated with increased physical activity during the follow-up.

CONCLUSION

Previous exercise habits and Qol after adjuvant chemo-, and radiotherapy were the strongest determinants of long-term physical activity levels in breast cancer survivors. Patients with better emotional functioning increased their exercise activity most as did those patients with higher fatigue levels at baseline. Patients suffering from fatigue after adjuvant treatment managed to increase their exercise levels, in contrast to patients with low emotional functioning, and may benefit from physical exercise interventions. Emotionally deprived patients may benefit from psychosocial support to regain their previous exercise levels.

Effects of non-supervised exercise interventions on bone mineral density in adult women: a systematic review and meta‑analysis

Osteoporosis is a major health issue worldwide. This study analyzes the effects of non-supervised osteoporosis prevention programs on bone mineral density. Non-supervised exercise increases femoral neck and lumbar spine bone mineral density in adult women. Thus, it might be effective for preventing or treating osteoporosis or osteopenia in this population.

INTRODUCTION

Osteoporosis is a major health issue worldwide. Social distancing measures due to COVID-19 have hindered the chances to take part in supervised osteoporosis prevention exercise programs. The purpose of the present study is to systematically review and meta-analyze the effects of non-supervised osteoporosis prevention exercise programs on bone mineral density (BMD) in adult women.

METHODS

A comprehensive search of electronic databases (n = 7) was conducted including (a) prospective randomized controlled trials (RCTs) comparing at least one exercise group vs. a control group with sedentary lifestyle or sham exercises; (b) baseline and follow-up BMD values, or BMD changes from baseline, at any skeletal site; (c) women over 30 years old; and (d) non-supervised exercise programs only. Subgroup analyses were performed for menopausal status, intervention duration, type of exercise, and osteopenia/osteoporosis status.

RESULTS

Ten studies were included (n = 668). Random effect analyses showed that unsupervised exercise had beneficial effects on lumbar spine (LS) BMD with standardized mean difference (SMD) = 0.40 (95% confidence interval (CI): 0.03-0.77), and femoral neck (FN) BMD with SMD = 0.51 (95% CI: 0.16-0.85). Unsupervised exercise increased LS (SMD = 0.73 (95% CI: 0.13-1.33)) and FN BMD (SMD = 0.85 (95% CI: 0.33-1.37)) in women with osteopenia/osteoporosis, but not in healthy counterparts.

CONCLUSION

Non-supervised exercise improves FN and LS BMD in adult women. Beneficial effects of exercise on FN and LS BMD might be more pronounced in those with poor bone health compared with healthy counterparts. More RCTs prescribing non-supervised, osteogenic exercise are required in this population. It is necessary to investigate the efficacy of remote/assistive technologies for delivering and monitoring non-supervised exercise interventions.

The Effect of Exercise for the Prevention of Bone Mass After Bariatric Surgery: a Systematic Review and Meta-analysis

We aimed to assess if exercise applied after bariatric surgery (BS) improves bone mineral density (BMD) compared to usual care. Systematic search was conducted up to January 2021. Effect measures were determined using standardized mean difference (SMD) with 95% confidence interval (CI). Certainty evidence was assessed according to GRADE. Four clinical trials encompassing 340 patients were included. Exercise induced a positive BMD effect at total hip (SMD = 0.37 [95% CI 0.02, 0.71]; very low certainty evidence), femoral neck (SMD = 0.63 [95% CI 0.19, 1.06]; low certainty evidence), lumbar spine (SMD = 0.41 [95% CI 0.19, 0.62]; low certainty evidence), and 1/3 radius (SMD = 0.58 [95% CI 0.19, 0.97]; low certainty evidence). Exercise undertaken after BS seems to induce a positive effect on BMD.

Physical activity accumulation along the intensity spectrum differs between children and adults

PURPOSE

Detailed exploration of physical activity accumulation with fine grading along the intensity spectrum has indicated the potential pragmatic utility of such an approach. However, it is currently unclear what sorts of accumulation patterns along particular intensity bands are found in the children and adult populations. Therefore, we conducted a comparison of activity accumulation in specific intensity bands between four distinct populations: children, adults with sedentary lifestyles, habitual joggers, habitual marathon runners.

METHODS

Free-living waist-worn accelerometry records from 28 children aged 7 to 11, and 61 adults aged 25 to 35 were analysed. Activity intensity was evaluated in 5 s non-overlapping epochs as mean amplitude deviation (MAD) and normalised to acceleration intensities corresponding to walking at 3 metabolic equivalents of a task (METs). Adult data were normalised to 0.091 g MAD based on literature, and data from children to 0.170 g MAD based on laboratory experimentation. The normalised epoch values were divided into 100 intensity gradations.

RESULTS

Children accumulated more activity in 0.74 to 1.58 normalised acceleration intensities (all p < 0.005) compared to adults. Adult joggers/runners accumulated more activity in normalised acceleration intensities from 7.1 to 11.1 compared to the other groups (p < 0.008).

CONCLUSION

The primary bulk of children's free-living activities are of relatively low intensity not likely to provoke cardiometabolic improvement. These sorts of explorations could be used in informing intervention development aiming at optimising healthy development. Evidence is mounting to justify randomised controlled trials based on intervention targets identified based on exploring the intensity spectrum.

Effects of Low Energy Availability on Bone Health in Endurance Athletes and High-Impact Exercise as A Potential Countermeasure: A Narrative Review

Endurance athletes expend large amounts of energy in prolonged high-intensity exercise and, due to the weight-sensitive nature of most endurance sports, often practice periods of dietary restriction. The Female Athlete Triad and Relative Energy Deficiency in Sport models consider endurance athletes at high-risk for suffering from low energy availability and associated health complications, including an increased chance of bone stress injury. Several studies have examined the effects of low energy availability on various parameters of bone structure and markers of bone (re)modelling; however, there are differences in findings and research methods and critical summaries are lacking. It is difficult for athletes to reduce energy expenditure or increase energy intake (to restore energy availability) in an environment where performance is a priority. Development of an alternative tool to help protect bone health would be beneficial. High-impact exercise can be highly osteogenic and energy efficient; however, at present, it is rarely utilized to promote bone health in endurance athletes. Therefore, with a view to reducing the prevalence of bone stress injury, the objectives of this review are to evaluate the effects of low energy availability on bone health in endurance athletes and explore whether a high-impact exercise intervention may help to prevent those effects from occurring.

Effects of High-Impact Weight-Bearing Exercise on Bone Mineral Density and Bone Metabolism in Middle-Aged Premenopausal Women: A Randomized Controlled Trial

This study examined the effects of high-impact weight-bearing exercise on bone mineral density (BMD) and bone metabolic markers in middle-aged premenopausal women. Forty middle-aged premenopausal women were initially enrolled, but thirty-one participants (40.34 ± 3.69 years) completed in the study. The subjects were randomly divided into two groups including the high-impact weight-bearing exercise group (HWE, n = 14) and control group (CON, n = 17). The HWE group participated in the exercise for 50 min a day, three days per week for four months, while the CON group maintained their regular lifestyle. The HWE program included 10 different high-impact weight-bearing exercises such as jumping and running. BMD was measured using DXA (Hologic, QDR 4500W, Marlborough, MA, USA). The bone metabolic markers including serum 25-(OH) D, intact parathyroid hormone (PTH), osteoprotegerin (OPG), osteopontin (OPN), receptor activator of nuclear factor κB ligand (RANKL), osteocalcin (OC), C-terminal telopeptide of type 1 collagen (CTX), and calcium were analyzed. The results showed that the BMDs of femur, lumbar, and forearm did not significantly change during the intervention period in both the HWE and CON groups. A significant decrease in bone formation markers such as OC (F = 10.514, p = 0.003, ηp2 = 0.266) and an increase in bone resorption marker including CTX (F = 8.768, p = 0.006, ηp2 = 0.232) were found only in the CON group, while these values did not change in the HWE group. There was a significant increase in serum 25-(OH) D (F = 4.451, p = 0.044, ηp2 = 0.133) in the HWE group. Our findings suggest that four months of HWE is not sufficient to improve BMD and bone metabolic markers, but this impact exercise program may prevent the age-associated changes in bone turnover markers in middle-aged premenopausal women.

Bilateral multidirectional jumps with reactive jump-landings achieve osteogenic thresholds with and without instruction in premenopausal women

BACKGROUND

Currently jump-landing ground reaction forces have only been quantified in the vertical direction as a stimulus for bone development. This study quantified the full-spectrum of jump-landing force magnitudes (body weight's) and rates of strain (body weights per second) of bilateral multidirectional jumps (star jump and stride jump) with reactive jump-landings (i.e. jumping immediately after initial jump-landing) among premenopausal women. It was also of interest to quantify the influence of instruction on the magnitude and rate of the jump-landing ground reaction forces.

METHODS

Twenty-one women [Mean (SD): 43.3(5.9)yr; 69.4(9.6)kg; 167(5.5)cm; 27.5(8.7)% body fat] performed a jump testing session 'with instruction' followed by a jump testing session performed one week later with 'instruction withdrawn'.

FINDINGS

The resultant magnitudes (3.90 to 5.38, body weights) and rates of strain (192 to 329, body weights per second) for the jump-landings, performed on a force plate, exceeded previously determined osteogenic thresholds (>3body weight's and >43body weights per second, respectively). An instruction effect was observed for resultant (↑8% and ↑12%; P ≤ .01) and vertical (↑8% and ↑7%; P ≤ .01) ground reaction force's (Newtons and body weight, respectively) indicating learning/practice effects for these exercises. A jump-landing effect was observed, with larger peak rates of strain (↑29%; P < .0001, body weight per second) and peak forces (↑12% to ↑48%; P ≤ .01, body weights) for the second jump-landing (post-reactive jump).

INTERPRETATION

These multidirectional bilateral jumps represent a unique training stimulus for premenopausal women and achieve osteogenic thresholds thought pre-requisite for bone growth and could be utilized in the development of osteogenic exercise programs.

Effects of Zumba® and Aquagym on Bone Mass in Inactive Middle-Aged Women

Background and objectives: Regular exercise may stimulate bone formation and reduce the loss of bone mass in premenopausal women. This study aims to evaluate the effect of high-impact physical activity (Zumba^®) and low-impact physical activity (Aquagym) on bone mass in inactive middle-aged women. Materials and methods: Fifty-five healthy inactive women (30⁻50 years old) were recruited in Spain in 2016 and were randomly allocated into one of three groups: High impact group (HIG: n = 15), low impact group (LIG: n = 12) and control group (CG: n = 28). HIG and LIG were recruited from Madrid and the CG from Toledo. HIG and LIG completed a 12-week intervention program with three 40' sessions per week of Zumba^® or Aquagym; respectively. Dual energy X-ray absorptiometry (DXA) measured bone mineral content (BMC) and areal bone mineral density (aBMD) at total body less head (TBLH), lumbar spine and right hip. Results: Post-intervention adjusted data showed no significant differences in BMC between any of the groups nor in aBMD between HIG and LIG. Interestingly; significant differences for the HIG vs. CG were found in the change in total hip aBMD (1.76% vs. -0.44%), femoral neck aBMD (1.80% vs. -2.71%), and intertrochanter aBMD (2.03% vs. -0.50%). Moreover, significant differences for the LIG vs. CG were also found in the change in femoral neck aBMD (-0.54% vs. -2.71%). Conclusions: The regular practice of Zumba^® and Aquagym might reduce the progressive deterioration of bone mass in inactive middle-aged women.

A systematic review of the exercise effect on bone health: the importance of assessing mechanical loading in perimenopausal and postmenopausal women

OBJECTIVE

The aims of this systematic review were to determine the general effects of exercise on areal bone mineral density (BMD) in perimenopausal and postmenopausal women, and to provide information on the most suitable bone-loading exercise regimens that may improve bone health in this population group.

METHODS

A computerized, systematic literature search was performed in the electronic databases PubMed, Web of Science, CINAHL, SPORTDiscus, and The Cochrane Library, from January 2005 to November 2015, to identify all randomized controlled trials related to exercise in perimenopausal and postmenopausal women. The initial search identified 915 studies, with a final yield of 10 studies. Only randomized controlled trials that examined the effects of exercise programs longer than 24 weeks in women aged 35 to 70 years were included. The 10 studies quantified at least BMD and described training variables adequately (training period, frequency, volume, intensity).

RESULTS

Ten studies with moderate quality evidence (6.4 ± 1.8 points, range 4-9) were included. Significant changes in lumbar and femoral neck BMD were found mainly with high-impact exercise and whole body vibration interventions.

CONCLUSIONS

While training effects must be interpreted with caution because of the heterogeneity of the protocols and exercises performed, this systematic review confirmed the effectiveness of impact exercises combined with other forms of training (vibration or strength training) to preserve BMD in perimenopausal and postmenopausal women. Despite the results possibly not representing a general dose-response relationship, we highlight the importance of quantifying loading intensity and frequency by means of accelerometry as these parameters are determinants for bone adaptation.

Do Bilateral Vertical Jumps With Reactive Jump Landings Achieve Osteogenic Thresholds With and Without Instruction in Premenopausal Women?

Jumps have been investigated as a stimulus for bone development; however, effects of instruction, jump type, and jump-landing techniques need investigation. This study sought to identify whether ground reaction forces (GRFs) for bilateral vertical jumps (countermovement jumps and drop jumps) with reactive jump-landings (ie, jumping immediately after initial jump-landing), with instruction and with instruction withdrawn, achieve magnitudes and rates of strain previously shown to improve bone mass among premenopausal women. Twenty-one women (Mean ± SD: 43.3 ± 5.9 y; 69.4 ± 9.6 kg; 167 ± 5.5 cm; 27.5 ± 8.7% body fat) performed a testing session 'with instruction' followed by a testing session performed 1 week later with 'instruction withdrawn.' The magnitudes (4.59 to 5.49 body weight [BW]) and rates of strain (263 to 359 BW·s^-1) for the jump-landings, performed on an AMTI force plate, exceeded previously determined thresholds (>3 BWs and >43 BW·s^-1). Interestingly, significantly larger peak resultant forces, (↑10%; P = .002) and peak rates of force development (↑20%; P < .001) values (in relation to BW and BW·s^-1, respectively) were observed for the second jump-landing (postreactive jump). Small increases (ES = 0.22-0.42) in all landing forces were observed in the second jump-landing with 'instruction withdrawn.' These jumps represent a unique training stimulus for premenopausal women and achieve osteogenic thresholds thought prerequisite for bone growth.

Exercise and Sports Science Australia (ESSA) position statement on exercise prescription for the prevention and management of osteoporosis

OBJECTIVES

Osteoporotic fractures are associated with substantial morbidity and mortality. Although exercise has long been recommended for the prevention and management of osteoporosis, existing guidelines are often non-specific and do not account for individual differences in bone health, fracture risk and functional capacity. The aim of the current position statement is to provide health practitioners with specific, evidence-based guidelines for safe and effective exercise prescription for the prevention or management of osteoporosis, accommodating a range of potential comorbidities.

DESIGN

Position statement.

METHODS

Interpretation and application of research reports describing the effects of exercise interventions for the prevention and management of low bone mass, osteoporosis and osteoporotic fracture.

RESULTS

Evidence from animal and human trials indicates that bone responds positively to impact activities and high intensity progressive resistance training. Furthermore, the optimisation of muscle strength, balance and mobility minimises the risk of falls (and thereby fracture), which is particularly relevant for individuals with limited functional capacity and/or a very high risk of osteoporotic fracture. It is important that all exercise programs be accompanied by sufficient calcium and vitamin D, and address issues of comorbidity and safety. For example, loaded spine flexion is not recommended, and impact activities may require modification in the presence of osteoarthritis or frailty.

CONCLUSIONS

Specific guidelines for safe and effective exercise for bone health are presented. Individual exercise prescription must take into account existing bone health status, co-morbidities, and functional or clinical risk factors for falls and fracture.

Physical activity estimated by the bone-specific physical activity questionnaire is also associated with cardiovascular risk

The nature of physical activity that benefits bone is traditionally thought to differ from that benefiting cardiovascular health. Accordingly, exercise recommendations for improving bone health and cardiovascular health are largely incongruent. Our aim was to determine the associations between high-impact physical activity participation and both cardiovascular disease risk factors and bone mass. We recruited 94 men and women (age 34.0 ± 13.3 years) to undergo measures of cardiovascular disease risk (BMI, total cholesterol, fasting blood glucose, waist-to-hip ratio, and mean arterial pressure) and dual-energy X-ray absorptiometry (DXA XR-800, Norland) measures of bone mass (femoral neck, lumbar spine, and whole body BMD) and body composition (whole body lean mass and fat mass). Physical activity participation was estimated using the bone-specific physical activity questionnaire (BPAQ). Those in the upper tertile for current BPAQ score exhibited lower total cholesterol, waist-to-hip ratio, and mean arterial pressure than those in the lower tertiles (P < 0.05) with the relationship being mild-to-moderate (r = -0.49 to 0.29, P < 0.01). Those in the upper tertile for BPAQ score also had greater lumbar spine BMD than those in the lower tertile (P = 0.008), with BPAQ score predicting 6% of the variance in BMD (P = 0.02). We conclude that high-impact physical activity as captured by the BPAQ may be beneficial for both bone health and for attenuating cardiovascular disease risk.

Simplified Tai Chi Resistance Training versus Traditional Tai Chi in Slowing Bone Loss in Postmenopausal Women

Background. This study examined whether simplified Tai Chi resistance training is superior to traditional Tai Chi in slowing bone loss in postmenopausal women. Methods. This prospective trial included 119 postmenopausal women (age: 52–65 years). Subjects were randomly assigned to participate in a traditional Tai Chi program (TTC, n = 40), a simplified Tai Chi resistance training program (TCRT, n = 40), or a blank control group (routine activity, n = 39). The TTC involved traditional Yang Style Tai Chi. The primary outcome was the change of lumbar bone mass density (L2–L4) at 12 months over the baseline. Femoral neck and Ward's triangle were also measured using dual-energy X-ray absorptiometry. Results. The L2–L4 density was significantly lower at 12 months in comparison to the baseline in the blank control group. In both the TCRT and TTC groups, the L2–L4 density was comparable to the baseline. There was a trend for less bone loss in the TCRT than in the TTC group. Similar findings were observed with femoral neck and Ward's triangle. Conclusion. Simplified Tai Chi resistance training could slow bone loss in menopausal women. The results also suggested, but did not confirm, superiority to traditional Tai Chi.

Efficiency of jumping exercise in improving bone mineral density among premenopausal women: a meta-analysis

BACKGROUND

Jumping exercise is frequently regarded as an optimum strategy for increasing pubertal bone growth, but its role in promoting or preserving adult bone mineral density (BMD) is still undefined.

OBJECTIVES

This meta-analysis aimed to evaluate the evidence for the influence of jumping exercise on BMD in premenopausal women and to define the effectiveness of high-impact exercise in improving or maintaining female bone health.

METHODS

We searched MEDLINE, PubMed, EMBASE, SPORTDiscus, Google Scholar and BIOSIS up to 1 September 2013 for jumping exercise influence on BMD in premenopausal women. The search terms used were 'jumping', 'skipping', 'brief exercise', 'high impact', 'bone density', 'BMD', 'femoral neck', 'lumbar spine', and 'trochanter', and the search was limited to females. Six papers met the search criteria.

RESULTS

Six studies on BMD in the femoral neck (Q = 2.63, p = 0.854, I (2) = 0.0 %), trochanter (Q = 2.10, p = 0.10, I (2) = 0.0 %) and lumbar spine (Q = 1.17, p = 0.979, I (2) = 0.0 %) were highly homogenous in determining skeletal responses to jumping exercise. Jumping exercise significantly increased BMD in the femoral neck {weighted mean difference (WMD) [fixed effect] = 0.017 g/cm(2), 95 % confidence interval (CI) 0.014-0.20, p < 0.001} and trochanter (WMD [fixed effect] = 0.021, 95 % CI 0.018-0.024, p < 0.001). However, the lumbar spine seemed to benefit less from such high-impact exercise (p = 0.181). Visual inspection of the plots implicated some degree of asymmetry, indicating a slightly positive treatment effect at the femoral neck and trochanter sites.

CONCLUSIONS

Based on meta-analysis of existing studies, the sensitivity of skeletal response to jumping exercise in premenopausal women is significant and site-specific, with significant benefit from high-impact exercise noted, especially at the hip.

Effects of lifestyle exercise on premenopausal bone health: a randomised controlled trial

Osteoporosis, a slowly evolving public health epidemic, often with an insidious presentation is largely preventable but the optimal dimensions of exercise that may be prescribed for enhancing bone-health among premenopausal adults are yet to be elucidated. Hence, the escalating incidence and burden of prevalence of osteoporosis is yet unabated. Considering that exogenous hormones in the form of hormonal contraception are known to modulate bone mass, investigations of their possible influence on the translation of exercise-induced osteogenic stimuli on the mature bone is pertinent. The aim of this study was to examine the effect of specified lifestyle exercise on bone-health of premenopausal women. Premenopausal women (n = 96, mean age: 22.25 ± 3.5 years; mean BMI: 23.43 ± 3.5 kg/m(2)) participated in a 6-month randomised controlled trial involving home-based rest-interspersed bouts of high-impact exercise for the intervention group and sham exercise for the control group. Approximately half (47) of the participants (24-exercise, 23-control) were on hormonal-based contraception while the other half (49: 24-exercise, 25-control) were not on hormonal contraception. The regime led to a significant 3.7 % increase in broadband ultrasound attenuation of exercisers compared to controls; hormonal contraceptive use did not appear to potentiate the osteogenic effects of the lifestyle exercise regime. The research highlights that short, discrete bouts of high-impact exercise may be a potential public health prescription for enhancing premenopausal bone-health regardless of hormonal contraceptive use.

Canadian Academy of Sport and Exercise Medicine position statement: osteoporosis and exercise

The purpose of this paper is to look at the effects of exercise in the treatment and prevention of osteoporosis in athletes of all age groups. Recommendations for exercise programs will be discussed as a tool to improve bone health. Medical management of osteoporosis will be reviewed mainly as it pertains to postmenopausal women.

The beneficial effect of leisure-time physical activity on bone mineral density in pre- and postmenopausal women

Regular exercise and physical activity (PA) are known to be protective factors for maintaining bone mineral density (BMD) and preventing osteoporotic fracture. We investigated the associations between leisure-time PA and BMD in 2,903 premenopausal and 2,267 postmenopausal women in Korea. BMDs of the lumbar spine and femur were measured using dual-energy X-ray absorptiometry. Leisure-time PA levels were assessed by a self-administrated questionnaire, and a total metabolic equivalent (MET) score was obtained. Regardless of menopausal status, performing more than moderate levels of leisure-time PA or total MET score had a significant positive association with BMD at both the lumbar spine and femur. In the premenopausal group, women whose total MET score was 1,050-1,500 (MET-min/week) appeared to have the highest lumbar spine and femoral BMD (p < 0.001). The associations between PA level and lumbar spine and femoral BMD were also shown in the postmenopausal group (p < 0.001). In addition, we found dose-response relationships between increasing exercise level and femoral BMD in both the premenopausal and postmenopausal groups. Our results indicate that a more than moderate level of leisure-time PA plays a role in maintaining BMD.

Real-world assessment of physical activity in glaucoma using an accelerometer

OBJECTIVE

To determine the association between glaucomatous visual field (VF) loss and the amount of physical activity and walking in normal life.

DESIGN

Prospective, observational study.

PARTICIPANTS

Glaucoma suspects without significant VF or visual acuity loss (controls) and glaucoma subjects with bilateral VF loss between 60 and 80 years of age.

METHODS

Participants wore an accelerometer over 7 days of normal activity.

MAIN OUTCOME MEASURES

Daily minutes of moderate or vigorous physical activity (MVPA) was the primary measure. Steps per day was a secondary measure.

RESULTS

Fifty-eight controls and 83 glaucoma subjects provided sufficient study days for analysis. Control and glaucoma subjects were similar in age, race, gender, employment status, cognitive ability, and comorbid illness (P>0.1 for all). Better-eye VF mean deviation (MD) averaged 0.0 decibels (dB) in controls and -11.1 dB in glaucoma subjects. The median control subject engaged in 16.1 minutes of MVPA daily and walked 5891 steps/day, as compared with 12.9 minutes of MVPA daily (P = 0.25) and 5004 steps/day (P = 0.05) for the median glaucoma subject. In multivariate models, glaucoma was associated with 21% less MVPA (95% confidence interval [CI], -53% to 32%; P = 0.37) and 12% fewer steps per day (95% CI, -22% to 9%; P = 0.21) than controls, although differences were not statistically significant. There was a significant dose response relating VF loss to decreased activity, with each 5 dB decrement in the better-eye VF associated with 17% less MVPA (95% CI, -30% to -2%; P = 0.03) and 10% fewer steps per day (95% CI, -16% to -5%; P = 0.001). Glaucoma subjects in the most severe tertile of VF damage (better-eye VF MD worse than -13.5 dB) engaged in 66% less MVPA than controls (95% CI, -82% to -37%; P = 0.001) and took 31% fewer steps per day (95% CI, -44% to -15%; P = 0.001). Other significant predictors of decreased physical activity included older age, comorbid illness, depressive symptoms, and higher body mass index.

CONCLUSIONS

Overall, no significant difference in physical activity was found between individuals with and without glaucoma, although substantial reductions in physical activity and walking were noted with greater levels of VF loss. Further study is needed to characterize better the relationship between glaucoma and physical activity.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Combination of Micronutrients for Bone (COMB) Study: bone density after micronutrient intervention

Along with other investigations, patients presenting to an environmental health clinic with various chronic conditions were assessed for bone health status. Individuals with compromised bone strength were educated about skeletal health issues and provided with therapeutic options for potential amelioration of their bone health. Patients who declined pharmacotherapy or who previously experienced failure of drug treatment were offered other options including supplemental micronutrients identified in the medical literature as sometimes having a positive impact on bone mineral density (BMD). After 12 months of consecutive supplemental micronutrient therapy with a combination that included vitamin D(3), vitamin K(2), strontium, magnesium and docosahexaenoic acid (DHA), repeat bone densitometry was performed. The results were analyzed in a group of compliant patients and demonstrate improved BMD in patients classified with normal, osteopenic and osteoporotic bone density. According to the results, this combined micronutrient supplementation regimen appears to be at least as effective as bisphosphonates or strontium ranelate in raising BMD levels in hip, spine, and femoral neck sites. No fractures occurred in the group taking the micronutrient protocol. This micronutrient regimen also appears to show efficacy in individuals where bisphosphonate therapy was previously unsuccessful in maintaining or raising BMD. Prospective clinical trials are required to confirm efficacy.

A meta-analysis of brief high-impact exercises for enhancing bone health in premenopausal women

A snapshot of current evidence from 6 randomised controlled trials for the effects of short bouts of high-impact exercises in 256 women via meta-analysis reveals that ample osteogenic response could be realised at the femoral neck and trochanter of premenopausal women with rest-inserted bouts of few mechanical bone loading cycles.

INTRODUCTION

Exercise is an important means of improving bone health and preventing osteoporosis. Brief bouts of simple exercises may be useful for aiding lifestyle compliance to physical activity. This study aimed to review the evidence on the effect of brief, high-impact exercise on bone health among premenopausal women.

METHODS

A structured and comprehensive search of databases was undertaken along with hand searching of key journals and reference lists to locate relevant studies published and unpublished up to January 2011. Six randomised controlled trials met predetermined inclusion criteria. Brief high-impact exercises (<30 min) were examined for their effect on bone mineral density (BMD) among premenopausal women. Trial quality was assessed using the Effective Public Health Practice Project quality assessment tool. Study outcomes for analysis, absolute change (grams per square centimetre) or relative change (in percent) in BMD at femoral neck, trochanter and lumbar spine were compared by calculating standardised mean difference (SMD) using fixed- and random effects models.

RESULTS

Quality of included trials varied from medium to high on a scale of 1 to 3. Brief bouts of exercise led to significant increases in femoral neck BMD (SMD = 0.64, 95% confidence interval (CI) = 0.38, 0.90, overall effect Z value = 4.84, p = 0.001); a modest increase in trochanteric BMD (SMD = 0.36, 95% CI = 0.10, 0.61, Z value = 2.08, p = 0.04) and no increase in spinal BMD (SMD = 0.04, 95% CI= -0.23, 0.31, Z value = 0.26, p = 0.79).

CONCLUSION

Based on the meta-analysis, brief high-impact exercise improves BMD at the hip but not at the lumbar spine. Effectiveness of this form of exercise as a lifestyle physical activity for prevention of osteoporosis should be explored in larger populations.

Exercise for bone health: rationale and prescription

PURPOSE OF REVIEW

Patients frequently inquire about exercise as a means to improve bone strength and reduce osteoporotic fracture. Understanding the biologic mechanisms and the available clinical evidence supporting the role of exercise in bone health is the key to an educated discussion.

RECENT FINDINGS

Exercise downregulates sclerostin expression by the osteocyte favoring osteoblastogenesis. These changes are enhanced by dynamic cyclical load with rest periods and may be promoted by low-amplitude high-frequency stimuli. In the prepubertal years, exercise results in periosteal gains, whereas exercise later in life maintains bone mass, reduces falls and probably associated fractures, and improves quality-of-life measures.

SUMMARY

Future studies should examine the effect of exercise on bone strength and determine the minimum quantity and frequency and the exercise type most effective to reduce osteoporotic fractures.

Multicomponent training program with weight-bearing exercises elicits favorable bone density, muscle strength, and balance adaptations in older women

Physical exercise is advised as a preventive and therapeutic strategy against aging-induced bone weakness. In this study we examined the effects of 8-month multicomponent training with weight-bearing exercises on different risk factors of falling, including muscle strength, balance, agility, and bone mineral density (BMD) in older women. Participants were randomly assigned to either an exercise-training group (ET, n = 30) or a control group (CON, n = 30). Twenty-seven subjects in the ET group and 22 in the CON group completed the study. Training was performed twice a week and was designed to load bones with intermittent and multidirectional compressive forces and to improve physical function. Outcome measures included lumbar spine and proximal femoral BMD (by dual X-ray absorptiometry), muscle strength, balance, handgrip strength, walking performance, fat mass, and anthropometric data. Potential confounding variables included dietary intake, accelerometer-based physical activity, and molecularly defined lactase nonpersistence. After 8 months, the ET group decreased percent fat mass and improved handgrip strength, postural sway, strength on knee flexion at 180°/s, and BMD at the femoral neck (+2.8%). Both groups decreased waist circumference and improved dynamic balance, chair stand performance, strength on knee extension for the right leg at 180°/s, and knee flexion for both legs at 60°/s. No associations were found between lactase nonpersistence and BMD changes. Data suggest that 8 months of moderate-impact weight-bearing and multicomponent exercises reduces the potential risk factors for falls and related fractures in older women.