***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: PURPOSE Individuals with osteoarthritis can experience difficulty walking and poor strength , possibly leading to falls and fractures . Exercise has been found to increase strength and bone mineral density . The purpose of this study was to determine the effects of 6 months of t'ai chi on knee muscle strength , bone mineral density , and fear of falling in older women with osteoarthritis . METHODS Eighty-two ( 82 ) women with osteoarthritis , recruited from outpatient clinics and community health centers , were r and omly assigned to either a t'ai chi group and took part in a t'ai chi program , or a control group . Of these , 30 subjects ( mean age = 63 years ) in the t'ai chi group and 35 ( mean age = 61 years ) in the control group completed post-test measures at 6 months . RESULTS After the 6-month study period , subjects in the t'ai chi program had significantly greater knee extensor endurance ( pre- to post-test mean increase = 36.4 W/kg , versus 1.1 W/kg for the controls ) , and significantly greater bone mineral density in the neck of the proximal femur ( mean change = 0.09 , versus -0.10 for the controls ) , Ward 's triangle ( mean change = 0.04 , versus -0.04 for the controls ) , and trochanter ( mean change = 0.07 , versus -0.05 for the controls ) than the controls . However , knee extensor and flexor strength did not differ significantly between the groups . The fear of falling during daily activities reduced significantly more in the t'ai chi group ( mean change = -2.40 , versus 0.66 for the controls ) . CONCLUSIONS T'ai chi increased knee extensor muscle endurance and bone mineral density in older women with osteoarthritis , and decreased their fear of falling during daily activities . Further study with long-term follow-up is needed to substantiate the role of t'ai chi exercise in the prevention of fall and its related fracture PURPOSE Tai Chi exercise , an ancient Chinese martial art , has drawn more and more attention for its health benefits . The purpose of the study was to identify the effects of a Sun-style Tai Chi exercise on arthritic symptoms ( joint pain and stiffness ) , motivation for performing health behaviors , and the performance of health behaviors among older women with osteoarthritis . METHODS Total of 72 women with the mean age of 63 years old were recruited from out patients clinic or public health centers according to the inclusion criteria and assigned r and omly to either the Tai Chi exercise group or the control . A Sun-style Tai Chi exercise has been provided three times a week for the first two weeks , and then once a week for another 10 weeks . In 12 weeks of study period , 22 subjects in the Tai Chi exercise group and 21 subjects in the control group completed the posttest measure with the dropout rate of 41 % . Outcome variables included arthritic symptoms measured by K-WOMAC , motivation for health behavior , and health behaviors . RESULTS At the completion of the 12 week Tai Chi exercise , the Tai Chi group perceived significantly less joint pain ( t=-2.19 , p=0.03 ) and stiffness ( t=-2.24 , p=0.03 ) , perceived more health benefits ( t=2.67 , p=0.01 ) , and performed better health behaviors ( t=2.35 , p=0.02 ) , specifically for diet behavior ( t=2.06 , p=0.04 ) and stress management ( t=2.97 , p=0.005 ) . CONCLUSION A Sun-style Tai Chi exercise was found as beneficial for women with osteoarthritis to reduce their perceived arthritic symptoms , improve their perception of health benefits to perform better health behaviors Background Osteoarthritis is the most common reason for pain in older adults , and the individual and economic burden of this disease is immense . The chronic character of osteoarthritis requires a long-term therapeutic treatment . In this regard life-style interventions such as physical exercises that can be carried out by the patient himself are recommended as first line treatment . There is evidence for the short-term benefit of exercise therapy in terms of pain reduction and physical functioning . Nonetheless research agendas highlight the need for multifaceted interventions that incorporate exercise strategies into patient care . Studies should be conducted with appropriate sample sizes and should allow statements on long-term effects as well as cost-utility and safety . These open questions are under the scope of this study . Methods / design This is a controlled study in the context of health services research . The study population consists of n = 1400 subjects with hip or knee osteoarthritis . The  intervention group will be recruited from participants of a country-wide health insurance offer for people with hip or knee osteoarthritis . Potential participants for the control group ( ratio 10:1 ( control vs. intervention ) will be filtered out from the insurance data base according to pre-defined matching criteria and asked by letter for their participation . The final statistical twins from the responders ( 1:1 ) will be determined via propensity score matching . The progressive training intervention comprises 8 supervised group sessions , supplemented by home exercises ( 2/week over 11 weeks ) . Exercises include mobilization , strengthening and training of postural control . Primary outcomes are pain and function measured with the WOMAC Index immediately after the intervention period . Among other things , health related quality of life , self-efficacy , cost utility and safety will be evaluated as secondary outcomes . Participants will be followed up 6 , 12 and 24 month after baseline . Discussion Results of this trial will document the effects of clinical as well as economic outcomes in a regular health care setting on the basis of a large sample size . As such , results of this trial might have great impact on future implementations of group- and home-based exercises in hip or knee osteoarthritis . Trail registration German Clinical Trial Register DRKS00009251 . Registered 10 September 2015 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 prospect i ve trial included 119 postmenopausal women ( age : 52–65 years ) . Subjects were r and omly 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 Background Knee osteoarthritis ( OA ) causes pain and long-term disability with annual healthcare costs exceeding $ 185 billion in the United States . Few medical remedies effectively influence the course of the disease . Finding effective treatments to maintain function and quality of life in patients with knee OA is one of the national priorities identified by the Institute of Medicine . We are currently conducting the first comparative effectiveness and cost-effectiveness r and omized trial of Tai Chi versus a physical-therapy regimen in a sample of patients with symptomatic and radiographically confirmed knee OA . This article describes the design and conduct of this trial . Methods / Design A single-center , 52-week , comparative effectiveness r and omized controlled trial of Tai Chi versus a st and ardized physical-therapy regimen is being conducted at an urban tertiary medical center in Boston , Massachusetts . The study population consists of adults ≥ 40 years of age with symptomatic and radiographic knee OA ( American College of Rheumatology criteria ) . Participants are r and omly allocated to either 12 weeks of Tai Chi ( 2x/week ) or Physical Therapy ( 2x/week for 6 weeks , followed by 6 weeks of rigorously monitored home exercise ) . The primary outcome measure is pain ( Western Ontario and McMaster Universities WOMAC ) subscale at 12 weeks . Secondary outcomes include WOMAC stkiffness and function domain scores , lower extremity strength and power , functional balance , physical performance tests , psychological and psychosocial functioning , durability effects , health related quality of life , and healthcare utilization at 12 , 24 and 52 weeks . Discussion This study will be the first r and omized comparative-effectiveness and cost-effectiveness trial of Tai Chi versus Physical Therapy in a large symptomatic knee OA population with long-term follow up . We present here a robust and well- design ed r and omized comparative-effectiveness trial that also explores multiple outcomes to eluci date the potential mechanisms of mind-body effect for a major disabling disease with substantial health burdens and economic costs . Results of this study are expected to have important public health implication s for the large and growing population with knee OA.Trial registration Clinical Trials.gov identifier : BACKGROUND The beneficial role of exercise in improving bone mineral density , muscle strength and balance , has been documented predominantly in younger population s. These findings may not apply to elderly population s with limited ability to perform exercises of high intensity . OBJECTIVE To examine the effects of Tai Chi ( TC ) and resistance exercise ( RTE ) on bone mineral density ( BMD ) , muscle strength , balance and flexibility in community living elderly people . DESIGN R and omised controlled trial , using blocked r and omization with stratification by sex . SETTING A community in the New Territories Region of Hong Kong , China . SUBJECTS One hundred eighty subjects ( 90 men , 90 women ) aged 65 - 74 , were recruited through advertisements in community centres . METHODS Subjects were assigned to participate in TC , RTE three times a week , or no intervention ( C ) for 12 months . Measurements were carried out at baseline , 6 and 12 months . Analyses of covariance ( ANCOVA ) adjusted for age , and baseline values of variables that were significantly different between groups : i.e. smoking and flexibility for men ; quadriceps strength for women . RESULTS Compliance was high  ( TC 81 % , RTE 76 % ) . In women , both TC and RTE groups had less BMD loss at total hip compared with controls . No effect was observed in men . No difference in either balance , flexibility or the number of falls was observed between either intervention or controls after 12 months . CONCLUSION The beneficial effects of TC or RTE on musculoskeletal health are modest and may not translate into better clinical outcomes Objective : To evaluate the effects of Tai Chi Qigong training on the quality of life and physical function of patients with osteoarthritis of the knee . Design : A preliminary , single-blind , r and omized controlled trial . Setting : General community , performed at Hwaseong City Health Center . Participants : Forty-four elderly subjects ( mean age , 69.1 ± 5.4 years ) with knee osteoarthritis . Intervention : The patients were r and omized ( 2:1 ) to : ( 1 ) an eight-week Tai Chi Qigong training programme or ( 2 ) a waiting list control group . The programme involved eight weeks of group Tai Chi Qigong sessions , with 60 minutes per session twice a week . Main outcome measures : The primary outcome was quality of life measured with the Short Form 36 ( SF-36 ) at baseline and week 8 . Secondary outcomes included the Western Ontario and McMaster University Osteoarthritis Index ( WOMAC ) and 6-m walking time . Results : The training group had statistically significant improvements in the quality of life ( changes of SF-36 , Qigong versus control : 21.6 ± 16.8 versus 9.8 ± 13.6 , P<0.05 ) and 6-m walking test ( change in walking time , Qigong versus control : —1.6 ± 1.7 versus —0.2 ± 0.8 s , P<0.01 ) . The WOMAC scores in the training group were markedly improved , although the differences were not statistically significant . Conclusions : Tai Chi Qigong training appears to have beneficial effects in terms of the quality of life and physical functioning of elderly subjects with knee osteoarthritis . However , more rigorous trials are needed to confirm the efficacy of this training for patients with osteoarthritis of the knee Background : Tai chi ( TC ) is proposed as a potential option for the management of osteoarthritis ( OA ) , however , its beneficial effect on patients with knee OA has not been convincing . Objectives : To evaluate the effect of a 24-week TC program on physical functions in older Chinese women with knee OA . Methods : Thirty-five older Chinese women with knee OA were r and omized into TC group ( n = 18 ) and attention control ( wellness education and stretching ) group ( n = 17 ) . Subjects in the TC group practice d the 24-form simplified Yang-style TC 2 to 4 times a week for 24 weeks with frequency gradually increased . Physical function was assessed using the Western Ontario and McMaster University Osteoarthritis Index ( WOMAC ) , 6-minute walk distance and stair climb time . Results : Compared with the control group , the participants in TC group had statistically significant improvements in changes of the WOMAC total score ( 6.18 ± 2.13 vs. 1.71 ± 2.73 , P = 0.000 ) , the WOMAC pain sub 
    Output:
    
The results of meta- analysis revealed that the effects of Tai Chi Chuan were observed for physical components in the body functions and structures domain .
The effects favoring Tai Chi Chuan were observed in the physical component in the activities and participation domain .
The review revealed that Tai Chi Chuan had beneficial outcomes for patients with knee osteoarthritis .
The evidence -based results represented that it had small-to-moderate effects on body functions and structures , activities , and participation of physical component .
However , there was insufficient evidence to support that Tai Chi Chuan had beneficial mental effect