The roles of exercise and fall risk reduction in the prevention of osteoporosis

Short-Term Increased Physical Activity During Early Life Affects High-Fat Diet-Induced Bone Loss in Young Adult Mice

Mechanical stresses associated with physical activity (PA) have beneficial effects on increasing BMD and improving bone quality. However, a high-fat diet (HFD) and obesity tend to have negative effects on bone, by increasing bone marrow adiposity leading to increased excretion of proinflammatory cytokines, which activate RANKL-induced bone resorption. In the current study, whether short-term increased PA via access to voluntary wheel running during early life has persistent and protective effects on HFD-induced bone resorption was investigated. Sixty 4-week-old male C57BL6/J mice were divided into two groups postweaning: without or with PA (access to voluntary running wheel 7-8 km/day) for 4 weeks. After 4 weeks with or without PA, mice were further subdivided into control diet or HFD groups for 8 weeks, and then all animals were switched back to control diet for an additional 4 weeks. Mice from the HFD groups were significantly heavier and obese; however, after 4 weeks of additional control diet their body weights returned to levels of mice on continuous control diet. Using μ-CT and confirmed by pQCT of tibias and spines ex vivo, it was determined that bone volume and trabecular BMD were significantly increased with PA in control diet animals compared with sedentary animals without access to wheels, and such anabolic effects of PA on bone were sustained after ceasing PA in adult mice. Eight weeks of a HFD deteriorated bone development in mice. Unexpectedly, early-life PA did not prevent persistent effects of HFD on deteriorating bone quality; in fact, it exacerbated a HFD-induced inflammation, osteoclastogenesis, and trabecular bone loss in adult mice. In accordance with these data, signal transduction studies revealed that a HFD-induced Ezh2, DNA methyltransferase 3a, and nuclear factor of activated T-cells 1 expression were amplified in nonadherent hematopoietic cells. In conclusion, short-term increased PA in early life is capable of increasing bone mass; however, it alters the HFD-induced bone marrow hematopoietic cell-differentiation program to exacerbate increased bone resorption if PA is halted. © 2021 Arkansas Children's Nutrition Center. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

A concept analysis of confidence related to older people living with frailty

Aim

To describe and define a concept of confidence in the context of older people living with frailty, which is important to the worldwide healthy-ageing agenda preventing decline in independence and well-being.

Design

Concept analysis informed by Walker and Avant's eight-stage approach.

Methods

Electronic databases (MEDLINE, CINAHL and PsychINFO) from 1994-2018 were searched. Published studies exploring confidence and excerpts of papers referencing older people, frailty and confidence informed the concept analysis. Extracted attributes informed model case and additional case development. Appraisal of antecedents, consequences and empirical referents informed the final concept's construction.

Results

Three overall defining attributes of confidence were identified in this concept analysis: physical, psychological and social. A central feature is personal control, influencing internal and external factors. These control factors can be enabling factors (positive factors) or dis-enabling factors (negative factors), affecting the frail older persons overall physical health and mental well-being.

Timed up-and-go test is a useful predictor of fracture incidence

PURPOSE

The timed up-and-go (TUG) test is a validated screening tool to assess fall risk. This study evaluated the association between the TUG test and future fractures, which are a tangible clinical complication of falling.

METHODS

We included 1,070,320 participants who participated in the National Screening Program for Transitional Ages for Koreans aged 66 years old from 2009 to 2014. Among them, 355,753 women underwent dual-energy X-ray absorptiometry. TUG times were classified as <10 s or ≥10 s. The incidence of fractures, including vertebral, hip, and other sites, was determined using claims data from the National Health Information database.

RESULTS

During the mean follow-up period of 4.4 ± 1.8 years, participants with slow TUG times had a significantly increased risk of fractures compared with those who had normal TUG times: any fractures (adjusted hazard ratio [aHR] = 1.08, 95% confidence interval [CI] = 1.06-1.10), vertebral fracture (aHR = 1.14, 95% CI = 1.11-1.16), hip fracture (aHR = 1.21, 95% CI = 1.13-1.29), and other fractures (upper arm, forearm, and lower leg; aHR = 1.02, 95% CI = 1.00-1.05). Among women with bone mineral density (BMD) results, slow TUG performance was associated with an increased risk of fracture independent of BMD.

CONCLUSIONS

The TUG test, as an indicator of physical performance, can provide information about future fracture risk above that provided by BMD. Conducting the TUG test to assess fracture risk should be considered to improve fracture risk assessment and propose interventions to improve physical performance, thereby reducing fracture risk.

The Role of Exercises in Osteoporotic Fracture Prevention and Current Care Gaps. Where Are We Now? Recent Updates

INTRODUCTION

The primary non-pharmacological management recommended for patients with osteoporosis (OP) is exercise, but whether it should be high-force, resistive, or other means can be obscure.

OBJECTIVE

To describe the role of exercises in osteoporotic fracture prevention, identify effects and potential risks of high-force exercises, detect the optimal exercises to combat OP, and explore the challenges that might arise from interventions.

METHODS

A search on MEDLINE and Cochrane databases was conducted on the role of exercises in preventing osteoporotic fractures from 1989 onwards, leading to 40 results, including op-ed pieces, qualitative studies, randomized clinical trials (RCTs) (n=5), and RCT follow-up studies (n=1). Articles deemed relevant to the objectives were analyzed and summarized. Data on effects of vitamin D and calcium supplementation were later gathered from different sources as well.

RESULTS

High-intensity, resistive strength training provided the maximum benefit in increasing bone mineral density (BMD) levels, muscle mass, and reduction in fractures, while posture and balance exercises only improved mobility. High-force exercises did not increase fractures and were associated with increases in BMD. Interventions including exercises, vitamin D, and calcium intake had limited effect when used as single interventions, while vitamin D and calcium may potentially cause increases of cardiovascular events.

CONCLUSION

A long-term regular exercise program designed to improve postural stability, mobility, and mechanical efficiency, alongside an increased vitamin D and dietary calcium intake, is most effective in preventing OP and reducing osteoporotic fractures.

The Effect of Long-Term Exercise on the Production of Osteoclastogenic and Antiosteoclastogenic Cytokines by Peripheral Blood Mononuclear Cells and on Serum Markers of Bone Metabolism

Although it is recognized that the mechanical stresses associated with physical activity augment bone mineral density and improve bone quality, our understanding of how exercise modulates bone homeostasis at the molecular level is lacking. In a before and after trial involving 43 healthy adults, we measured the effect of six months of supervised exercise training on the spontaneous and phytohemagglutinin-induced production of osteoclastogenic cytokines (interleukin-1α, tumor necrosis factor-α), antiosteoclastogenic cytokines (transforming growth factor-β1 and interleukins 4 and 10), pleiotropic cytokines with variable effects on osteoclastogenesis (interferon-γ, interleukin-6), and T cell growth and differentiation factors (interleukins 2 and 12) by peripheral blood mononuclear cells. We also measured lymphocyte phenotypes and serum markers of bone formation (osteocalcin), bone resorption (C-terminal telopeptides of Type I collagen), and bone homeostasis (25 (OH) vitamin D, estradiol, testosterone, parathyroid hormone, and insulin-like growth factor 1). A combination of aerobic, resistance, and flexibility exercises done on average of 2.5 hours a week attenuated the production of osteoclastogenic cytokines and enhanced the production of antiosteoclastogenic cytokines. These changes were accompanied by a 16% reduction in collagen degradation products and a 9.8% increase in osteocalcin levels. We conclude that long-term moderate intensity exercise exerts a favorable effect on bone resorption by changing the balance between blood mononuclear cells producing osteoclastogenic cytokines and those producing antiosteoclastogenic cytokines. This trial is registered with Clinical Trials.gov Identifier: NCT02765945.

Low bone mineral density in COPD patients with osteoporosis is related to low daily physical activity and high COPD assessment test scores

COPD patients have an increased prevalence of osteoporosis (OP) compared with healthy people. Physical inactivity in COPD patients is a crucial risk factor for OP; the COPD assessment test (CAT) is the newest assessment tool for the health status and daily activities of COPD patients. This study investigated the relationship among daily physical activity (DPA), CAT scores, and bone mineral density (BMD) in COPD patients with or without OP. This study included 30 participants. Ambulatory DPA was measured using actigraphy and oxygen saturation by using a pulse oximeter. BMD was measured using dual-energy X-ray absorptiometry. OP was defined as a T-score (standard deviations from a young, sex-specific reference mean BMD) less than or equal to −2.5 SD for the lumbar spine, total hip, and femoral neck. We quantified oxygen desaturation during DPA by using a desaturation index and recorded all DPA, except during sleep. COPD patients with OP had lower DPA and higher CAT scores than those of patients without OP. DPA was significantly positively correlated with (lumbar spine, total hip, and femoral neck) BMD (r=0.399, 0.602, 0.438, respectively, all P<0.05) and T-score (r=0.471, 0.531, 0.459, respectively, all P<0.05), whereas CAT scores were significantly negatively correlated with (total hip and femoral neck) BMD (r=−0.412, −0.552, respectively, P<0.05) and (lumbar spine, total hip, and femoral neck) T-score (r=−0.389, −0.429, −0.543, respectively, P<0.05). Low femoral neck BMD in COPD patients was related to high CAT scores. Our results show no significant difference in desaturation index, low SpO₂, and inflammatory markers (IL-6, TNF-α, IL-8/CXCL8, CRP, and 8-isoprostane) between the two groups. Chest physicians should be aware that COPD patients with OP have low DPA and high CAT scores.

Musculoskeletal disorders in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a lung disease characterized by airway obstruction and inflammation but also accompanied by several extrapulmonary consequences, such as skeletal muscle weakness and osteoporosis. Skeletal muscle weakness is of major concern, since it leads to poor functional capacity, impaired health status, increased healthcare utilization, and even mortality, independently of lung function. Osteoporosis leads to fractures and is associated with increased mortality, functional decline, loss of quality of life, and need for institutionalization. Therefore, the presence of the combination of these comorbidities will have a negative impact on daily life in patients with COPD. In this review, we will focus on these two comorbidities, their prevalence in COPD, combined risk factors, and pathogenesis. We will try to prove the clustering of these comorbidities and discuss possible preventive or therapeutic strategies.

Balance control in elderly people with osteoporosis

Osteoporosis is a prevalent health concern among older adults and is associated with an increased risk of falls that incur fracture, injury, or mortality. Identifying the risk factors of falls within this population is essential for the development of effective regimes for fall prevention. Studies have shown that muscle quality and good posture alignments are critical for balance control in elderly individuals. People with osteoporosis often have muscle weakness and increased spine kyphosis leading to vertebral fractures and poor balance control, or even falls. Therefore, improving muscle quality, strengthening weak muscles, and correcting postural alignment are essential elements for the prevention of falls and fractures in older adults with osteoporosis. This review reports the necessary information regarding the critical factors of balance control in older adults with osteoporosis, as well as testing the clinical innovations of exercise training to improve the long-term prognosis of osteoporosis in this vulnerable population.

Physical activity improves age-related decline in the osteogenic potential of rats' bone marrow-derived mesenchymal stem cells

AIM

To examine whether physical activity increases osteogenic differentiation of bone marrow mesenchymal stem cells (BMMSCs) from adult rats compared with young rats.

METHODS

Eighteen female Wistar rats were divided into three groups and the following cells isolated: (1) differentiated BMMSCs from young donors, (2) differentiated BMMSCs from sedentary adult donors and (3) differentiated BMMSCs from active adult donors. We analysed MTT conversion, percentage of cells per field, mineralized nodule number and gene expression for telomerase reverse transcriptase (TERT), alkaline phosphatase, caspase 3, osteocalcin, bone sialoprotein and collagen I.

RESULTS

Telomerase reverse transcriptase expression and the percentage of cells per field in BMMSCs cultures from adult rats were smaller than those observed in young donors. However, levels of caspase 3 expression were higher in BMMSCs from adult donors (P < 0.05). Despite the fact that physical activity was associated with an increase in expression of caspase 3 (P < 0.05), there was no difference in the percentage of cells per field between groups of adult BMMSCs (active or sedentary). However, physical activity increased the number of mineralized nodules and osteocalcin expression after 21 days, and alkaline phosphatase expression at 7, 14 and 21 days in the BMMSCs of adult donors (P < 0.05). However, those values were smaller when compared with young donors BMMSCs (P < 0.05). Only the expression levels of alkaline phosphatase were similar to young donors BMMSCs (P ≥ 0.05).

CONCLUSION

Physical activity increases osteogenic differentiation of BMMSCs from adult donors but does not increase the differentiation to the levels observed in BMMSCs from young donor rats.

Effects of Long-Term Tai Chi Practice on Balance and H-Reflex Characteristics

The purpose of the present study was to examine the effects of long-term Tai Chi practice on postural balance and H-reflex. Sixteen healthy volunteers, eight with three or more years of experience in Tai Chi training (Tai Chi Group-TCG), and eight with no experience in Tai Chi training (Control Group-CG) participated in the study. Postural sways were measured under four experimental conditions: (1) Standing still with eyes open (EO); (2) Standing still with eyes closed (EC); (3) Standing and turning head to left and right with eyes open (EOT); and (4) Standing and turning head to left and right with eyes closed (ECT). Paired reflex depression (PRD) of the soleus muscle was measured under two conditions: supine and standing. Less significant postural sway was observed in the TCG than in the CG under four conditions including EO, EC, EOT, and ECT (p < 0.01). The TCG demonstrated 14.1%, 30.6%, 33.3% and 22.7% less postural sway, respectively. Significant PRD change from a supine to standing position was observed between TCG and CG (p < 0.05). A significant correlation between PRD change (from supine to standing) and years of Tai Chi practice was observed (r = 0.80, p < 0.05). The findings of this study support the positive effects of Tai Chi exercise on balance control under different conditions. Long-term Tai Chi exercisers also demonstrated different reflex modulation from a supine to standing position, and long-term Tai Chi practice may lead to a change of PRD modulation as neuroadaptation.

[Is there a place for the physical activity in the prevention of the fractures of chronic kidney disease patients?]

The risk of non-traumatic fractures is greatly increased in kidney disease patients and well demonstrated in dialysis patients. If osteoporosis plays a major role in the general population, in chronic kidney disease renal osteodystrophy is associated with neurological and muscular disorders, which probably worsen the risk. The decrease in physical activity is a factor contributing to the loss of bone mass and the initiation of a rehabilitation program improves the prognosis. Despite the association between chronic renal disease and sedentary lifestyle, the relationship between physical inactivity and bones in dialysis patients and the effect of increased activity programs, are not well documented in the literature.

Osteoporosis: nonpharmacologic management

Osteoporosis is a chronic disorder of the skeleton causing increased bone fragility and fractures. In the second of our 3-part series, we discuss the beneficial effects of nonpharmacologic agents in the management of osteoporosis. We review the evidence supporting the use of exercise, whole-body vibration, hip protectors, low-intensity pulsed ultrasound, bracing, and vertebral augmentation procedures. The mechanism of action, precautions, and expected outcomes are discussed. Nonpharmacologic management of osteoporosis blends in very well with an overall exercise prescription. The nonpharmacologic interventions discussed are readily available and easy to implement. The use of such techniques demonstrates the important role of the physiatrist in the management of osteoporosis.

Effects of martial arts on health status: a systematic review

OBJECTIVE

To systematically summarize the evidence for the effects of martial arts on health and fitness, to show the strengths of different types of martial arts, and to get a more complete picture of the impacts of martial arts on health, and also to provide a basis for future research on martial arts as an exercise prescription in exercise therapy.

METHOD

We searched for "martial arts""health" and "random" in eight databases (n= 5432). Randomized controlled trials and controlled clinical trials on the health effects of martial arts were included in the study.

RESULTS

The final analysis included 28 papers (one general martial arts, one kung fu, sixteen tai chi, six judo, three karate, and one taekwondo). Among the disciplines of martial arts, tai chi was the most well-studied, followed by judo, karate, and taekwondo. Research topics varied widely, and included health, injuries, competition, morals and psychology, and herbal medicine. Most found positive effects on health. Tai chi is no-contact, low-impact, soft body and mindfulness exercise, which has been widely adopted by elderly people and proven to be a beneficial health promotion exercise. Research on judo, karate, and taekwondo mainly focused on improvements to athletes' competitive abilities, rather than on health effects. We did not find any published randomized controlled trials or controlled clinical trials on aikido, kendo, sumo, kyudo, qi gong, or other disciplines.

DISCUSSION AND CONCLUSION

Since martial arts are widely practiced, their effects on physiology, morphology, immunology, and neurology should be further studied in order to help people to select the best discipline or style to accomplish their purposes. This necessitates categorizing and classifying the disciplines and styles according to their effects on different body systems and levels of contact, as well as standardizing evaluation criteria for martial arts. Martial arts as an exercise prescription can then move from an experience-based to an evidence-based treatment.

Physical activity slows femoral bone loss but promotes wrist fractures in postmenopausal women: a 15-year follow-up of the OSTPRE study

Results on fracture risk among physically active persons are contradictory. The aim of this study was to investigate the long-term association between the self-reported physical activity (PA), the risk of fractures, and bone loss among peri- and postmenopausal women. The association between PA and fracture risk was examined during 15 years of follow-up in the population-based Osteoporosis Risk Factor and Prevention (OSTPRE) Study among 8560 women with a mean age of 52.2 years (range 47 to 56 years) at baseline. The amount and type of PA, as well as the types and mechanisms of fractures, were registered with self-administered questionnaires at 5-year intervals (ie, 1989, 1994, 1999, and 2004). A total of 2641 follow-up fractures were verified in 2073 women (24.2%). The study cohort was divided into quartiles by average hours of reported PA during the whole follow-up. Areal bone mineral density (aBMD) at the proximal femur (n = 2050) and lumbar spine (L(2)-L(4); n = 1417) was followed at 5-year intervals from a random stratified subsample with dual X-ray absorptiometry (DXA). Risk of fracture was estimated by using the Cox proportional hazards model with a mean follow-up time of 15.2 years. Weekly average time spent on leisure-time PA was 0.4, 1.7, 3.3, and 7.0 hours from the least to the most active quartiles, respectively. The risk of wrist fracture was higher in the active quartiles (II to IV) than in the most inactive quartile (I), with hazard ratios (HRs) of 1.3 [95% confidence interval (CI) 1.05-1.57, p = .014] for the second (II), 1.2 (95% CI 1.01-1.51, p = .045) for the third (III), and 1.4 (95% CI 1.14-1.69, p = .001) for the fourth (IV) quartile, respectively. Overall, most of the fractures were reported as a result of a fall (69.0%), with a 2.1 times higher rate of wrist fractures during the winter (November to April) than during summer season. There were no significant associations of PA with any other fracture types. Bone loss at the femoral neck, trochanter, and Ward's triangle was significantly associated with long-term PA (ANCOVA p < .05), whereas no associations of bone loss and PA in lumbar spine were seen. PA is associated with a moderate rise in wrist fracture risk, which might be explained in part by a higher number of outdoor activities. Regular PA of at least 1½ hours per week does not seem to increase the risk of other fractures and might significantly decrease proximal femur bone loss among peri- and postmenopausal women.

Increased circulating adiponectin levels and decreased leptin/soluble leptin receptor ratio throughout puberty in female ballet dancers: association with body composition and the delay in puberty

INTRODUCTION

Ballet dancers (BDs) have a negative energy balance related to physical training that results in alterations in body composition, sexual development, and adipokine secretion. Our aims were to study anthropometric parameters, body composition, and their relationship with adipokines throughout pubertal development.

SUBJECTS AND METHODS

We carried out a prospective follow-up study of 22 female Caucasian BDs (Tanner II stage) followed throughout puberty. Nutritional status was determined by measurement of height, weight, and body mass index (BMI). We calculated growth velocity, bone maturity, and body composition at Tanner stages II, III, and V by dual energy X-ray absorptiometry. Circulating leptin, adiponectin, and soluble leptin receptor (sObR) levels were determined.

RESULTS

BDs presented a delay in skeletal maturation during puberty, without affectation of final height. Energy intake was deficient according to their physical exercise, and they had a delay of 1 year in the mean age of menarche. Leptin levels were decreased, whereas sObR and adiponectin levels were increased throughout puberty. The percentage of trunk fat, total fat mass, and fat of the extremities was decreased throughout the study period (P<0.01). Lean mass was increased in the lower extremities, and bone mineral density was normal.

CONCLUSION

A negative energy balance together with maintained physical exercise induced modifications in body composition in BDs. Changes in leptin and adiponectin levels appear to be more related to total fat content than to BMI. Furthermore, the onset and delayed progress of puberty may be related with an inadequate energy balance due to increased exercise.

The relationship between adipokines, body composition, and bone density in men with chronic obstructive pulmonary disease

Osteoporosis is common in patients with chronic obstructive pulmonary disease (COPD). Data regarding the relationship between adipokines and bone mineral density (BMD) in this population is lacking. The purpose of this pilot study was to determine associations between the adipokines tumor necrosis factor-alpha (TNF-α), leptin, adiponectin and resistin, body composition, and BMD in men with severe COPD. This was a cross-sectional study of men with severe COPD who visited the University of Colorado Hospital COPD Center. Bone density and parameters of body composition were measured by dual-energy X-ray absorptiometry. Twenty-three men were included (mean age = 66 years, mean percent predicted forced expiratory volume in one second = 32%). On bivariate analysis, there was no association between TNF-α and BMD. Parameters of body composition and serum concentrations of leptin and adiponectin were significantly associated with total hip and spine bone density. However, with partial correlation analysis, total body mass was the only independent predictor of total hip BMD, explaining approximately 50% of the variability. Overall, 18 out of 23 men enrolled (78%) had low bone density by T-score, and nine (39%) were classified as having osteoporosis. The men with osteoporosis had lower parameters of body composition, lower mean serum leptin concentrations, and a greater impairment in measures of lung function compared to the men without osteoporosis. We conclude that the effect of adipokines on BMD does not appear to be independent of body mass. However, larger studies are needed to further evaluate the relationship between adipokines, body weight, and BMD in patients with COPD.

Risk factors for bone mineral density at the calcaneus in 40-59 year-old male workers: a cross-sectional study in Korea

Background

Few epidemiologic studies have attempted to investigate the prevalence and risk factors for osteopenia and osteoporosis in middle-aged Asian men. We performed this study to determine the prevalence and risk factors of osteopenia and osteoporosis in this population.

Methods

This cross-sectional study was conducted from March to July, 2004. The subjects were 2,073 males aged from 40 to 59 years in the KHNP (Korea Hydro & Nuclear Power) workplace-based cohort. Bone mineral density (BMD) was measured by peripheral, dual-energy, X-ray absorptiometry (DXA) at the calcaneus. Anthropometric and lifestyle factors were investigated using a standard, self-reported questionnaire.

Results

BMD was 0.60 ± 0.09 g/cm² (mean ± standard deviation) and was negatively correlated with age (r = -0.18, P < 0.001), but positively correlated with waist-to-hip ratio (WHR; r = 0.15, P < 0.001), body fat (r = 0.10, P < 0.001), BMI (r = 0.35, P < 0.001), height (r = 0.26, P < 0.001), and weight (r = 0.43, P < 0.001).

In multiple linear regression analysis, the independent determinants associated with BMD were increasing age (coefficient = -0.002, P < 0.001), physical activity (≤ 2/week vs. ≥ 3/week; coefficient = 0.017, P < 0.001), WHR (coefficient = -0.796, P < 0.001), body mass index (BMI; coefficient = 0.023, P < 0.001) and smoking status (never vs. ever; coefficient = -0.018, P < 0.001).

Conclusion

We suggest that BMD of the calcaneus is correlated negatively with exposure to smoke and increased WHR, but positively with regular exercise and increased BMI.

Enhancement of the adolescent murine musculoskeletal system using low-level mechanical vibrations

Mechanical signals are recognized as anabolic to both bone and muscle, but the specific parameters that are critical to this stimulus remain unknown. Here we examined the potential of extremely low-magnitude, high-frequency mechanical stimuli to enhance the quality of the adolescent musculoskeletal system. Eight-week-old female BALB/cByJ mice were divided into three groups: baseline controls (BC, n = 8), age-matched controls (AC, n = 12), and whole body vibration (WBV, n = 12) at 45 Hz (0.3 g) for 15 min/day. Following 6 wk of WBV, bone mineralizing surfaces of trabeculae in the proximal metaphysis of the tibia were 75% greater (P < 0.05) than AC, while osteoclast activity was not significantly different. The tibial metaphysis of WBV mice had 14% greater trabecular bone volume (P < 0.05) than AC, while periosteal bone area, bone marrow area, cortical bone area, and the moments of inertia of this region were all significantly greater (up to 29%, P < 0.05). The soleus muscle also realized gains by WBV, with total cross-sectional area as well as type I and type II fiber area as much as 29% greater (P < 0.05) in mice that received the vibratory mechanical stimulus. The small magnitude and brief application of the noninvasive intervention emphasize that the mechanosensitive elements of the musculoskeletal system are not necessarily dependent on strenuous, long-term activity to initiate a structurally relevant response in the adolescent musculoskeletal system. If maintained into adulthood, the beneficial structural changes in trabecular bone, cortical bone, and muscle may serve to decrease the incidence of osteoporotic fractures and sarcopenia later in life.

Tai chi for osteoporosis: a systematic review

INTRODUCTION

Tai chi may have beneficial effects with respect to balance, falls and non-vertebral fractures. The purpose of this systematic review was to evaluate evidence from controlled clinical trials testing the effectiveness of tai chi for osteoporosis.

METHODS

Systematic searches were conducted on 20 electronic databases. The outcome measures considered for inclusion were changes in bone parameters.

RESULTS

Five randomized clinical trials (RCTs) and two controlled clinical trials (CCT) met all inclusion criteria. In postmenopausal women, one RCT found tai chi to be superior for loss of bone mineral density (BMD) compared with sedentary lifestyle, while two other RCTs found no differences between tai chi and exercises or calcium supplementation for BMD. The meta-analysis showed no significant effect of tai chi on BMD change at the spine compared with no treatment in postmenopausal women. One RCT failed to show favorable effects of tai chi compared with resistance training (RT) for total hip BMD in elderly women. A further RCT compared tai chi with RT on bone metabolism and reported favorable effects compared with RT in the elderly.

CONCLUSION

The evidence for tai chi in the prevention or treatment of osteoporosis is not convincing. More rigorous research seems warranted.

Low-level, high-frequency mechanical signals enhance musculoskeletal development of young women with low BMD

The potential for brief periods of low-magnitude, high-frequency mechanical signals to enhance the musculoskeletal system was evaluated in young women with low BMD. Twelve months of this noninvasive signal, induced as whole body vibration for at least 2 minutes each day, increased bone and muscle mass in the axial skeleton and lower extremities compared with controls.

INTRODUCTION

The incidence of osteoporosis, a disease that manifests in the elderly, may be reduced by increasing peak bone mass in the young. Preliminary data indicate that extremely low-level mechanical signals are anabolic to bone tissue, and their ability to enhance bone and muscle mass in young women was investigated in this study.

MATERIALS AND METHODS

A 12-month trial was conducted in 48 young women (15-20 years) with low BMD and a history of at least one skeletal fracture. One half of the subjects underwent brief (10 minutes requested), daily, low-level whole body vibration (30 Hz, 0.3g); the remaining women served as controls. Quantitative CT performed at baseline and at the end of study was used to establish changes in muscle and bone mass in the weight-bearing skeleton.

RESULTS

Using an intention-to-treat (ITT) analysis, cancellous bone in the lumbar vertebrae and cortical bone in the femoral midshaft of the experimental group increased by 2.1% (p = 0.025) and 3.4% (p < 0.001), respectively, compared with 0.1% (p = 0.74) and 1.1% (p = 0.14), in controls. Increases in cancellous and cortical bone were 2.0% (p = 0.06) and 2.3% (p = 0.04) greater, respectively, in the experimental group compared with controls. Cross-sectional area of paraspinous musculature was 4.9% greater (p = 0.002) in the experimental group versus controls. When a per protocol analysis was considered, gains in both muscle and bone were strongly correlated to a threshold in compliance, where the benefit of the mechanical intervention compared with controls was realized once subjects used the device for at least 2 minute/day (n = 18), as reflected by a 3.9% increase in cancellous bone of the spine (p = 0.007), 2.9% increase in cortical bone of the femur (p = 0.009), and 7.2% increase in musculature of the spine (p = 0.001) compared with controls and low compliers (n = 30).

CONCLUSIONS

Short bouts of extremely low-level mechanical signals, several orders of magnitude below that associated with vigorous exercise, increased bone and muscle mass in the weight-bearing skeleton of young adult females with low BMD. Should these musculoskeletal enhancements be preserved through adulthood, this intervention may prove to be a deterrent to osteoporosis in the elderly.

Efeito da atividade física no osso normal e na prevenção e tratamento da osteoporose

A osteoporose é uma doença cada vez mais diagnosticada em mulheres e homens de todo o mundo. Embora os esteróides sexuais sejam importantes na gênese da osteoporose, a inatividade física constitui um fator de risco. O exercício físico atua no osso por efeito direto, via força mecânica, ou indireto, mediado por fatores hormonais. Mas os mecanismos pelos quais a atividade física melhora a massa óssea ainda não são totalmente conhecidos. Baseando-se nos resultados que demonstram os efeitos benéficos da atividade física no tecido ósseo, a prática de esportes vem sendo cada vez mais indicada na prevenção e até mesmo no tratamento da osteoporose. O objetivo desta revisão é descrever os efeitos da atividade física no tecido ósseo normal e na prevenção e tratamento da osteoporose.

Diet, activity, and other lifestyle risk factors for forearm fracture in postmenopausal women in China: a case-control study

OBJECTIVE

Forearm fractures are a major cause of disability in postmenopausal women, but the risk factors have not been previously studied in China and the results from Western studies may not be applicable to the Chinese population. The aim of this study was to determine whether calcium intake, activity level, lifestyle, and other factors are associated with risk of forearm fracture among Chinese postmenopausal women.

DESIGN

In this case-control study, the authors used a structured questionnaire to assess potential risk factors in 209 postmenopausal women 50 to 70 years old with new forearm fractures identified in eight hospitals in Chengdu and in age and location of residence-matched control subjects randomly selected from the community.

RESULTS

Adjusted odds ratios (95% CIs) were as follows: each quintile increase in current energy intake 0.46 (0.36, 0.60); fifth quintile energy-adjusted current calcium intake versus lowest quintile, 0.17 (0.06, 0.47); eating bean products when 30 to 49 years old, 0.15 (0.05, 0.47); eating meat, 0.13 (0.02, 0.74) and eating pork ribs, 0.37 (0.17, 0.83) when 16 to 29 years old; greater past activity, 0.78 (0.68, 0.89) and present activity, 0.84 (0.74-0.96); greater height (per centimeter), 1.12 (1.06, 1.20); each year irregular menses before menopause, 1.25 (1.04, 1.49); each floor of residence, 1.71 (1.38, 2.12); and prior fracture in first- or second-degree relatives, 2.74 (1.08, 6.92).

CONCLUSION

Some risk factors for forearm fractures were similar to those described in white women, whereas others were specific to this ethnic setting, and would need to be considered in future preventive programs.

Exercise Intervention Designed to Improve Strength and Dynamic Balance among Community-Dwelling Older Adults

Loss of balance and falling are critical concerns for older adults. Physical activity can improve balance and decrease the risk of falling. The purpose of this study was to evaluate a simple, low-cost exercise program for community-dwelling older adults. Sixteen senior adults were evaluated using the Senior Fitness Test for measures of functional strength, aerobic endurance, dynamic balance and agility, and flexibility. In addition, measures of height, weight, resting blood pressure, blood lipids, and cognitive function were obtained. Participants then attended a 10-week exercise class including stretching, strengthening, and balance-training exercises. At the completion of the program, significant improvements were observed in tests measuring dynamic balance and agility, lower and upper extremity strength, and upper extremity flexibility. The results indicate that exercise programs such as this are an effective, low-cost solution to improving health and factors that affect falling risk among older adults.

A randomized, prospective study of the effects of Tai Chi Chun exercise on bone mineral density in postmenopausal women 11No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors(s) or upon any organization with which the author(s) is/are associated

OBJECTIVE

To evaluate the potential benefits of programmed Tai Chi Chun (TCC) exercise on the weight-bearing bones of early postmenopausal women.

DESIGN

Age-matched and randomized prospective intervention.

SETTING

University medical school.

PARTICIPANTS

One hundred thirty-two healthy postmenopausal women (mean age, 54.0+/-3.5y) within 10 years of menopause onset were recruited and randomized into the TCC exercise group (n=67) or the sedentary control group (n=65).

INTERVENTION

Supervised TCC exercise was performed by the TCC group for 45 minutes a day, 5 days a week, for 12 months; control subjects retained a sedentary life style. Main outcome measures Bone mineral density (BMD) was measured in the lumbar spine and proximal femur by using dual-energy x-ray absorptiometry and in the distal tibia by using multislice peripheral quantitative computed tomography (pQCT). All BMD measurements were repeated after 12 months in both groups. Fracture rate was also documented.

RESULTS

Baseline measurements showed homogeneity in age, anthropometric variables, and menstruation status between the TCC and control groups. Exactly 81.6% of the subjects in the TCC group and 83.1% of subjects in the control group completed the 12-month follow-up study. BMD measurements revealed a general bone loss in both TCC and sedentary control subjects at all measured skeletal sites, but with a reportedly slower rate in the TCC group. A significant 2.6- to 3.6-fold retardation of bone loss (P<.01) was found in both trabecular and cortical compartments of the distal tibia in the TCC group as compared with the controls, as measured by pQCT. A total of 4 fracture cases were documented during follow-up, including 3 subjects in the control group and 1 in the TCC group.

CONCLUSIONS

This is the first prospective and randomized study to show that a programmed TCC exercise intervention is beneficial for retarding bone loss in weight-bearing bones in early postmenopausal women. Long-term follow-up is needed to substantiate the role of TCC exercise in the prevention of osteoporosis and its related fracture.

Are the 'hard' martial arts, such as the Korean martial art, TaeKwon-Do, of benefit to senior citizens?

Falls are a leading cause of death in the elderly. Associated with aging is a loss of muscular strength, flexibility, and coordination. Regular exercise is widely believed to be of benefit for the elderly. To this end, various exercise regimes have been employed to battle the associated problems of aging. One such has been the Chinese martial art, Tai Chi Chuan (TC). TC as an exercise system uses slow smooth movements to train the body in balance, endurance, and strength. For this reason, it is known as a 'soft' martial art, in that it is very non-impact oriented. There have been a variety of studies in the West examining the beneficial effects of TC. However, to date, there have been no studies with senior citizens using other martial arts, of which, TC is but one. The present study was designed to examine the appropriateness and effects of a Korean martial art known as TaeKwon-Do (TKD), a 'hard' martial art, on an elderly population measuring similar parameters reported for TC. Of those participants that attended >85% of classes, an increase was observed in the average number of push-ups, trunk flexion, and balance time on each foot. TKD proved effective at increasing one-leg balance in the population examined. Additionally, the overall dropout rate was extremely low suggesting both that the elderly are capable of participating in a hard martial art and that they have an interest in it as a viable alternative to other forms of exercise. The present study suggests that TKD as a form of exercise for an elderly population is both viable and potentially popular and warrants further study.

Regular Tai Chi Chuan exercise may retard bone loss in postmenopausal women: A case-control study

OBJECTIVE

To evaluate the potential benefits of regular Tai Chi Chuan exercise on the weight-bearing bones of postmenopausal women.

DESIGN

Case-control study.

SETTING

University medical school in Hong Kong.

PARTICIPANTS

Postmenopausal women (age range, 50-59y), including 17 self-selected regular Tai Chi Chuan exercisers (TCE) with over 4 years of regular exercise, and 17 age- and gender-matched nonexercising controls (CON).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Bone mineral density (BMD) in the lumbar spine and proximal femur was measured at baseline and at follow-up 12 months later by using dual-energy x-ray absorptiometry (DXA) and in the distal tibia using multislice peripheral quantitative computed tomography (pQCT).

RESULTS

Baseline results showed that the TCE group had significantly higher BMD (10.1%-14.8%, all P<.05) than the CON group in the lumbar spine, proximal femur, and the ultradistal tibia. The follow-up measurements showed generalized bone loss in both groups. Although both DXA and pQCT measurements revealed decelerated rates of bone loss in the TCE group, only the more sensitive pQCT showed significantly reduced rate of bone loss in trabecular BMD of the ultradistal tibia (TCE vs CON: -1.10%+/-1.26% vs -2.18%+/-1.60%, P<.05) and of cortical BMD of the distal tibial diaphysis (TCE vs CON: -0.90%+/-1.36% vs -1.86%+/-0.93%, P<.05).

CONCLUSION

This is the first case-control study to show that regular Tai Chi Chuan exercise may help retard bone loss in the weight-bearing bones of postmenopausal women.

Evaluation of the effectiveness of Tai Chi for improving balance and preventing falls in the older population--a review

One of the challenges faced by people with advancing age is decreased postural stability and increased risks for falls. There has been an increased interest over the last decade in using Tai Chi as an intervention exercise for improving postural balance and preventing falls in older people. Despite the increased number of studies in recent years relating Tai Chi to balance and fall prevention, results are scattered and inconsistent. There is wide variation in the use of balance measures, subject population, type and duration of Tai Chi exercise, and type of study. This paper provides a systematic review/analysis of currently available study reports. The goal of the review is to address the following concerns: how the effect of Tai Chi on balance or fall prevention has been evaluated to date, what level of evidence exists supporting Tai Chi as an effective exercise for improving balance or preventing falls, and what factors could possibly affect the benefit of Tai Chi on balance or falls. This review also helps identify directions for future research.

COPD and osteoporosis

Osteoporosis, with resulting fractures, is a significant problem in patients with advanced COPD. The etiology for the bone loss is diverse but includes smoking, vitamin D deficiency, low body mass index, hypogonadism, sedentary lifestyle, and use of glucocorticoids. Effective strategies to prevent bone loss and/or to treat osteoporosis include calcium and vitamin D, hormone replacement when indicated, calcitonin, and bisphosphonate administration. However, many patients remain undiagnosed until their first fracture because of the lack of recognition of the disease. With an increased awareness by pulmonologists and the increased use of preventive strategies, the impact of osteoporosis on those patients with COPD should decrease.

Effects of an osteoporosis prevention program incorporating tailored educational materials

PURPOSE

To evaluate the effects of two interventions on calcium intake and exercise and assess whether intervention effects varied as a function of participants' stage of change.

DESIGN

The study used a 2 by 2 factorial research design. Baseline, 3-, 6-, and 12-month follow-up data were collected.

SETTING

Twelve counties in western North Carolina.

SUBJECTS

Of 714 women recruited, 547 (76.6%) completed all data collection procedures.

INTERVENTION

One intervention, conducted at the individual level, compared the effects of tailored vs. nontailored educational materials. The tailored educational intervention was delivered via two packets of written materials and one telephone counseling session. The written materials and counseling session were tailored according to participants' current calcium intake and exercise level, perceived adequacy of these behaviors, stage of change, behavioral goals, and perceived barriers to change. A community-based intervention was also evaluated. This intervention, implemented in 6 of the 12 counties, included establishing an Osteoporosis Resource Center, conducting a workshop on osteoporosis prevention, and offering free bone density screening.

MEASURES

Outcome measures were calcium intake and exercise level. Stage of change was assessed as a moderating variable.

RESULTS

Irrespective of intervention group, among women not consuming adequate calcium at baseline, intake increased an average of about 500 mg/d over the course of the study. Changes involving exercise were more modest. Repeated measures regression analyses were used to evaluate intervention effects. The effect of the tailored educational intervention varied, in appropriate ways, among women in different stages of change at baseline (F2,527 = 6.37, p < .002). Among women in the Engaged stage, the tailored intervention was associated with a greater increase in calcium intake. In contrast, among women who were obtaining adequate calcium at baseline (i.e., Action stage), the tailored intervention appeared to forestall inappropriate increases in calcium intake. The community-based intervention had no consistent effects on calcium intake, either alone, or in combination with the tailored intervention. Finally, neither intervention had an effect on exercise, either alone or in combination.

CONCLUSIONS

Limited support for the superiority of tailored vs. nontailored educational interventions was found. The differential effects observed could be due to the telephone counseling received by women in the Tailored Education Group, however.

Increasing weight-bearing physical activity and calcium intake for bone mass growth in children and adolescents: a review of intervention trials

OBJECTIVE

The purpose of this review is to evaluate the current state-of-the-science for interventions to increase bone mass gains in children and adolescents using weight-bearing physical activity or calcium supplementation.

METHODS

Studies were located using computerized and manual searches of the empirical literature. Inclusion criteria were: (a) intervention study targeting weight-bearing physical activity or calcium intake; (b) inclusion of a control group; (c) subject age range under 18 years; and (d) outcome measured bone mineral density or bone mineral content.

RESULTS

Weight-bearing physical activity and calcium supplement intervention studies both consistently show positive effects on bone mass gains in children and adolescents. The most consistent findings for both weight-bearing physical activity and calcium were for lumbar spine and total body bone sites. Only weight-bearing physical activity interventions had significant effects on the femoral neck sites. Low power may have contributed to the lack of statistically significant findings in several studies and also prevented proper evaluation of potential interactions between pubertal status and interventions on bone mass gains.

CONCLUSIONS

Increases in weight-bearing physical activity or calcium intake have positive effects on bone mass gains in children and adolescents. Further research is needed to evaluate: (a) the long-term durability of these effects; (b) specific dose-response associations; (c) interactions between weight-bearing physical activity and calcium intake; and (d) interactions between pubertal development and weight-bearing physical activity or calcium intake on bone mass outcomes.

Economic costs of obesity and inactivity

PURPOSE

The purpose of this paper is to assess the economic costs of inactivity (including those attributable to obesity). These costs represent one summary of the public health impact of increasingly sedentary populations in countries with established market economies. Components of the costs of illness include direct costs resulting from treatment of morbidity and indirect costs caused by lost productivity (work days lost) and forgone earnings caused by premature mortality.

METHODS

We searched the Medline database for studies reporting the economic costs of obesity or inactivity, or cost of illness. From the identified references those relating to obesity or conditions attributable to obesity were reviewed. Chronic conditions related to inactivity include coronary heart disease (CHD), hypertension, Type II diabetes, colon cancer, depression and anxiety, osteoporotic hip fractures, and also obesity. Increasing adiposity, or obesity, is itself a direct cause of Type II diabetes, hypertension, CHD, gallbladder disease, osteoarthritis and cancer of the breast, colon, and endometrium. The most up-to-date estimates were extracted. To estimate the proportion of disease that could be prevented by eliminating inactivity or obesity we calculated the population-attributable risk percent. Prevalence based cost of illness for the U.S. is in 1995 dollars.

RESULTS

The direct costs of lack of physical activity, defined conservatively as absence of leisure-time physical activity, are approximately 24 billion dollars or 2.4% of the U.S. health care expenditures. Direct costs for obesity defined as body mass index greater than 30, in 1995 dollars, total 70 billion dollars. These costs are independent of those resulting from lack of activity.

CONCLUSION

Overall, the direct costs of inactivity and obesity account for some 9.4% of the national health care expenditures in the United States. Inactivity, with its wide range of health consequences, represents a major avoidable contribution to the costs of illness in the United States and other countries with modern lifestyles that have replaced physical labor with sedentary occupations and motorized transportation.