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Systematic Reviews

Tai Chi Combined With Resistance Training for Adults Aged 50 Years and Older: A Systematic Review

Qi, Meiling MS1,2; Moyle, Wendy PhD1,2; Jones, Cindy PhD1,2; Weeks, Benjamin PhD2,3

Author Information
Journal of Geriatric Physical Therapy: January/March 2020 - Volume 43 - Issue 1 - p 32-41
doi: 10.1519/JPT.0000000000000218
  • Free

Abstract

INTRODUCTION

Age-related physiological changes affect the functioning of all body systems and as a result, the prevalence of physical limitations and falls increases in adults aged 50 years and older.1,2 Aging also brings with it an increased risk of mental or neurological disorders, with one of the most common neuropsychiatric disorders in older adults being depression.3 In addition, aging is also associated with reduced muscle strength and physical performance.4,5 Chronic disease, hearing loss, and cognitive impairment are also associated with declining health-related quality of life (HRQOL) in older adults.6,7 Exercise is an important undertaking for people of any age and can help overcome some of the problems of aging.8,9 For instance, moderate-intensity physical activity participation is associated with a lower risk of depressive symptoms,10 and aerobic exercise, in particular, improves functional fitness (eg, aerobic endurance, leg muscle strength, balance, and mobility).11

Tai Chi, a type of psychophysiological exercise, is one of the many activities that can have beneficial effects for older adults and, in particular, for preventing falls.12 This exercise emphasizes breathing control, stable rhythm, weight shifting, and balance.13,14 Participation in Tai Chi has been shown to improve physical fitness and psychological well-being, including reducing stress, depression, anxiety, and pain.15–17 Resistance training, also called strength training or weighted training, has been associated with marked improvements in muscle strength and physical function.18,19 Resistance training has also been reported to have a positive effect on depression and anxiety.20 Various devices can be used to facilitate resistance training, for example, elastic bands, weight machines, and weighted vests.21 Therefore, it is likely that combining resistance training with Tai Chi exercise may further promote and enhance physical function and psychological well-being compared with Tai Chi exercise or resistance training only. Few studies have evaluated the effects of Tai Chi incorporating a resistance training (TCRT) program. For example, 1 study indicated that the TCRT program has been shown to improve muscle strength in older adults with a mean age of 65.3 years compared with Tai Chi exercise only.22

Previous systematic reviews have investigated the benefits of Tai Chi or resistance training in terms of their individual impact on the health of older adults aged 65 years and older.23,24 Systematic reviews have not considered the combined impact of TCRT on health outcomes in older adults. “Older adults” in the American College of Sports Medicine and the American Heart Association physical activity and public health recommendation25 refers to individuals aged 65 years and older. But these recommendations are also relevant for adults aged 50 to 64 years, with clinically significant chronic conditions and/or functional limitations. “Older women” in studies about physical function decline and domestic violence also refers to adults aged 50 years and older.26,27 Given the authors are interested in improving physical and psychological functioning in older adults, the decision was made to include articles related to adults aged 50 years and older.

This systematic review focuses on existing literature that evaluated the effects of a TCRT program on health outcomes in adults aged 50 years and older. The operational definition of health outcomes used in this systematic review is a change in the health of an individual, or a group of population, which is wholly or partially attributed to an intervention or a series of interventions.28 Health outcomes can be categorized into physical health, psychological well-being, social health, pain, HRQOL, disease, impairment, and life expectancy.

METHODS

Registry of the Systematic Review Protocol

The protocol of this review complied with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) Guidelines.29 It was prospectively registered with the International Prospective Register of Systematic Reviews (PROSPERO) (registration number CRD42017069692).

Literature Search

A systematic literature search was conducted in the following 7 major bibliographic databases: PubMed, Scopus, Web of Science, CINAHL, MEDLINE, Physiotherapy Evidence Database (PEDro), and the Cochrane library from the earliest available year of publication of the topic to January 2018. Manual searches were subsequently performed through reference lists of relevant articles. Search terms were based on controlled terms from Medical Subject Headings (MeSH) in PubMed. Search terms representing “Tai Chi” were used in combination with search terms representing “resistance” and “older adults.” Key word searches were performed on titles, abstracts, and key words. The full search strategy for all databases is provided in Appendix 1.

Inclusion Criteria

Original quantitative experimental studies were included and restricted to full-text manuscripts published in English. Conference abstracts, literature reviews, and theses were excluded. The Population Intervention Comparison Outcomes framework30 was used to evaluate the suitability of studies for inclusion as follows: (1) population: adults aged 50 years and older; (2) intervention: one of the interventions was a Tai Chi combined with resistance training program; (3) comparison: any control or comparison group; and (4) outcomes: health outcomes including physical health, psychological health, pain, HRQOL, and impairment.

Selection Process and Quality Assessment

Titles and abstracts of articles identified through the search process were reviewed firstly by 1 author (M.Q.) to exclude articles out of scope. Subsequently, 2 authors (M.Q. and C.J.) independently reviewed the full texts of all potentially relevant articles for eligibility. Disagreements were discussed and resolved with a third author (W.M.). The levels of agreement between the reviewers were assessed by a Cohen κ score. The score was classified as follows: less than 0.2 as poor, 0.21 to 0.40 as fair, 0.41 to 0.60 as moderate, 0.61 to 0.80 as substantial, and 0.81 to 1.00 as almost perfect agreement.31 The PEDro scale was applied to assess the quality of eligible studies as it has sufficient validity for use in systematic reviews on physical therapy.32 Each study received 1 point for each scale item if a criterion was clearly satisfied or zero if insufficient information was provided to determine the quality. Any author disagreements were resolved by discussion and consensus.

Data Extraction

For each eligible study, 1 reviewer (M.Q.) independently extracted important information and entered it into Tables 1 and 2. Table 1 ranks the methodological quality of the included studies. Table 2 provides a summary of each study including author names, year of publication, study design, participant demographics, dropout rate, participant attendance, intervention frequency and duration, outcome measures, and study results. Author disagreements were resolved by discussion.

Table 1. - PEDro Quality Assessment Results (n = 7)
Studies Lin et al33 Robitaille et al38 Su et al22 Wang et al34 Wang et al37 Zeng et al35 Zhuang et al36
Randomized allocation 1 0 1 1 1 1 1
Concealed allocation 0 0 0 0 1 1 1
Similarity between groups at baseline 1 1 1 1 1 1 1
Blinding of all participants 0 0 0 0 0 0 0
Blinding of all therapists 0 0 0 0 1 0 0
Blinding of all outcome assessors 1 1 0 0 1 1 0
Dropout rate <15% 1 1 0 1 1 0 1
All received treatment or key outcome was analyzed by “intention-to-treat” 0 0 0 0 1 0 0
Between-group statistical comparisons 1 1 1 1 1 1 1
Both point and variability measures provided 1 1 1 1 1 1 1
Total (0-10) 6/10 5/10 4/10 5/10 9/10 6/10 6/10

Table 2. - Summary of Tai Chi Combined With Resistance Training Exercise Trials for Adults Aged 50 Years and Older (n = 7)
Authors and Location Study Design Participants, Dropout, Attendance Intervention Frequency and Duration Outcome Measures Results
Lin et al,33 Taiwan Cluster RCT • 108 people, older than 65 y (mean age of 74.0 y)
• Dropout rate: 12% (dropout and relocation)
• TCRT group: 15-min warm-up, 30-min TCRT (manipulating the Thera-bands by both hands while performing 10 simple Tai Chi forms), and 15-min cooldown. Twice weekly for 16 wk.
• Control group: routine activities.
• Functional fitness
○ Arm curl
○ Chair-stand-up
○ Back scratch
○ Chair sit-and-reach
○ 6-min walk
○ 8-ft up and go
• Muscle strength
• TCRT group performed significantly better than the control group on upper body strength, lower extremities flexibility, dynamic balance, and aerobic endurance, with exception of lower body strength and upper body flexibility (P < .001).
• TCRT group significantly improved both muscle strength of upper and lower extremities, with the exception of right hip flexion compared with the control group (P < .001).
Robitaille et al,38 Canada Quasi-experimental design • 200 older adults, older than 60 y (mean age of 73.9 y)
• Dropout rate: 11.5% (loss of motivation, availability, and health issues)
• Attendance: 78%
• Intervention group: Tai Chi movements and leg strengthening exercises with elastic bands, 1 group-based session, and 1 home-based practice per week for 12 wk.
• Control group: No exercise.
• Static balance
• Stability limits
• Mobility
• Lower extremity muscles
• Walking speed
• Grip strength
• The intervention significantly improved static balance, and mobility.
Su et al,22 China Multiple-armed RCT • 49 older adults (mean age of 65.3 y) • TC group: Four to five 60-min sessions per week for 4 mo.
• TCRT group: Four to five 60-min sessions of weighted TC (Tai Chi training wearing a weighted vest) per week for 4 mo.
• Control group: no intervention.
• Lower limb isokinetic muscle strength • TCRT group had significant improvement on lower extremities muscle strength compared with the TC group (P < .05).
• TCRT group had significant improvement on lower extremities muscle strength compared with the control group (P < .05).
Wang et al,34 China Multiple-armed RCT • 119 postmenopausal women, aged 52-65 y (mean age of 58.5 y)
• Dropout rate: 10.9% (time conflicts and low attendance)
• Control group: Routine living.
• TC group: Yang-style Tai Chi, 4 times a week for 60 min each for 12 mo.
• TCRT group: simplified TCRT (4 Chen-style actions, each consists of 8 movements. Resistance was incorporated into the last module), 4 times a week for 60 min each, for 12 mo.
• BMD of the lumbar L2-L4 region, femoral neck, and Ward triangle • L2-L4 BMD significantly increased in TCRT group compared with baseline (P = .01).
• No significant difference among the 3 groups, with higher L2-L4 BMD in the TCRT group (P = .06).
Wang et al,37 China Multiple-armed RCT • 90 older adults, aged 60-70 y (mean age of 65.5 y)
• Dropout rate: 12.2% (dropout, scheduled conflict, low attendance)
• Control group: routine living.
• TC group: Yang-style Tai Chi, 4 times a week for 60 min each, for 6 mo.
• TCRT group: simplified TCRT (4 Chen-style actions, each consists of 8 movements. Resistance was incorporated into the last module), 4 times a week for 60 min each, for 6 mo.
• FMS tests
○ Deep squat
○ Hurdle step
○ In-line lunge
○ Shoulder mobility
○ Active straight leg rise
○ Trunk stability push-up
○ Rotary stability
• FMS scores significantly improved in both TC and TCRT groups compared with baseline (P < .001), while no difference was found in the control group.
• TCRT group had significantly higher FMS scores than the control group.
• TCRT group showed higher improvement in hurdle step, leg rise, push-up, and rotary compared with TC and control groups.
Zeng et al,35 China RCT • 81 patients with THA, aged 60-69 y (mean age of 65.0 y). Dropout rate: 27.2% (dropout and health problem) • TCRT group: 45-60 min 10 simplified Tai Chi training, 20- to 30-min hip muscle strength training (putting sandbags on the foot) and ROM training for 12 wk, at least 5 times per week, and one-to-one preoperative education program.
• Control group: Preoperative education
• WOMAC
• 6MWT
• TUG
• UPST
• ROM
  • TCRT group performed significant improvement in exercise tolerance, mobility, and self-reported functional statue compared with the control group (P < .01).

  • TCRT group performed significant improvement in the ROM abduction ability (P < .05).

Zhuang et al,36 China RCT • 56 community-dwelling older adults, aged 60-80 y (mean age of 65.9 y). Dropout rate: 10.7% (time conflicts and transportation difficulties) • TCRT group: 5-min warm-up, 15-min balance exercises, 15-min muscle-strength training (targeting the lower extremities and posture muscles), and 15-min 8-form Yang-style Tai Chi, ending with 10-min flexibility/stretching and cooldown. 60-min per class, 3 times per week for 12 wk.
• Control group: maintain usual level of physical activity.
• Physical performance
○ CS-30
○ TUG
○ FR
○ SEBTs
• Lower limb isokinetic strength
• Gait analysis
○ Speed
○ Cadence
○ Step length
  • TCRT group demonstrated significant improvement in lower body strength and endurance and dynamic balance and mobility compared with the control group (P < .001).

  • TCRT group also demonstrated significant improvement in both knee and ankle isokinetic strength compared with the control group (P < .001).

Abbreviations: BMD, bone mineral density; 6MWT, 6 Minute Walk Test; CS-30, 30-second Chair Stand Test; FMS, functional movement screen; FR, functional reach test; RCT, randomized controlled trial; ROM, range of motion; SEBTs, star excursion balance tests; TC, Tai Chi; TCRT, Tai Chi resistance training; THA, total hip arthroplasty; TUG, time up and go; UPST, unipedal stance test; WOMAC, Western Ontario and McMaster Universities Osteoarthritis Index.

RESULTS

A total of 648 articles were identified: 111 in PubMed, 143 in Scopus, 234 in Web of Science, 41 in CINAHL, 41 in MEDLINE, 29 in PEDro, 43 in Cochrane, and 6 by manual search. Of these, 321 articles were identified as duplicates and removed, leaving 327 articles. The titles and abstracts of the 327 articles were initially reviewed. After 254 out-of-scope articles were removed, the full text of 73 potential studies was independently assessed for eligibility. There was a high level of agreement between the 2 authors (κ = 0.91, P < .001). Seven articles satisfied the inclusion criteria22,33–38 and were included in this systematic review (see the Figure).

Figure.
Figure.:
PRISMA flow diagram to identify studies to include in the systematic review. RT indicates Resistance training; TC, Tai Chi; TCRT, Tai Chi incorporating a resistance training.

Characteristics of Included Studies

Quality assessment

The quality of included studies ranged from 4 to 9 on the PEDro scale, with an average score of 5.9, and 4 studies were classified as high quality (Table 1). Generally, a low-quality study classification was mainly attributed to selection bias (unconcealed allocation), performance bias (failure to blind therapists), measurement bias (failure to blind participants and assessors), and failure to use an intention-to-treat analysis. The review found that the participants were not blinded to group allocation in any of the included studies. Also, only 1 of the studies applied an intention-to-treat analysis.37 However, this was neither feasible nor practical, given the nature of the studies. Assessors were blinded to outcome measures and group allocation to avoid measurement bias in 4 studies.33,35,37,38 In addition, only 1 study blinded the therapists to avoid performance bias.37 To avoid selection bias, 3 of the studies used random numbers, computer-generated numbers, and envelope-based randomizations to allocate participants to either the intervention group or the control group.35–37 However, the remaining 4 studies did not describe the specific methods of randomized allocation.22,33,34,38 All 7 studies reported between-group differences with point estimates and measures of validity.

Participants and outcomes

The 7 studies in this systematic review involved a total of 703 participants aged 50 years and older, including healthy older adults,22,33,36,37 older adults with a history of falls,38 healthy postmenopausal women,34 and patients following total hip arthroplasty (THA).35 Four main intervention study designs were represented, including multiple-armed randomized controlled trials,22,34,37 randomized controlled trials,35,36 cluster randomized trials,33 and quasi-experiments.38 Five studies were conducted in mainland China,22,34–37 1 in Taiwan,33 and 1 in Canada.38

For the health outcome measures, a variety of reliable and valid assessment tests were undertaken, including Functional Movement Screen37; Timed Up and Go Test35,36; Chair-Sit-and-Reach Test33; 30-second Chair Stand Test33,36; Functional Reach Test36,38; Arm Curl Test33; Back-Scratch Test33; 6-Minute Walk Test33,35; Star Excursion Balance Tests36; Western Ontario and McMaster Universities Osteoarthritis Index35; and Bone Mineral Density measurement34 (Table 2).

Dropout rate, attendance, and adverse events

Of the 7 included trials, 1 study did not report a dropout rate.22 The other 6 studies reported an average dropout rate of 14.1% from 10.7%36 to 27.2%.35 The high dropout rate was mainly due to dropout without explanation, time conflict, relocation, transportation difficulties, and health problems. Most of the included studies did not report participants' attendance rates, with only 1 study38 specifically indicating that participants' attendance was 78% during the 12-week TCRT exercise program. Wang et al34 reported that participants with low attendance were not included in the final data analysis, which is not consistent with an intention-to-treat analysis principle. None of the other studies reported adverse effects from TCRT. Although patients suffered from quadriceps muscle weakness after THA surgery,39 the researchers demonstrated that “there was no wound infections, joint dislocations, or major medical complications in all patients” after a 12-week TCRT intervention involving patients with THA.35

Effects of TCRT

Across all studies, the interventions were varied with respect to the style of Tai Chi exercise training and resistance training and the duration and frequency of the exercise program. The frequency and duration of the TCRT programs ranged from 2 hours to 7.5 hours per week and 12 weeks to 12 months, respectively. Of the 7 trials, 3 used a nonexercise control group33,36,38 and 1 used a one-to-one preoperative education program control group.35 Three studies compared TCRT intervention with both the Tai Chi control group and a nonexercise control group.22,34,37 All of the 7 studies involved supervised group exercise.

The most common TCRT exercise was Tai Chi, followed by resistance training. Zhuang et al36 applied strength training, including standing on toes and body weight squats, as well as the 8-form Yang-style Tai Chi. Wang et al34 and Wang et al37 performed Chen-style Tai Chi, incorporated with resistance training in their last module. Zeng et al35 used the 10 simplified forms of Tai Chi, followed by hip muscle training using sandbags to apply resistance to the ankle during lower limb exercises. Robitaille et al38 applied Tai Chi movements and leg-strengthening exercise with elastic bands of varying thickness. In addition, 2 studies incorporated resistance training while performing Tai Chi, using Thera-band resistance exercise,33 and wearing a weighted vest.22 However, no specific Tai Chi forms were mentioned in any of these studies.

Effects of TCRT on physical function

Three studies found TCRT to be superior for improvement of aerobic endurance compared with either a nonexercise group33,36 or a preoperative education group.35 The TCRT significantly improved the 6-Minute Walk scores from 401.5 m (SD = 70.4) at pretest to 429.6 m (SD = 67.2) at posttest compared with the nonexercise program with older adults aged 65 years and older over a 16-week period,33 and from 409.6 m (SD = 51.3) at pretest to 478.1 m (SD = 52.5) at posttest compared with an education program in patients with THA aged 60 to 69 years over a 12-week period.35 Three studies33,36,38 suggested that the TCRT intervention improved dynamic balance compared with the nonexercise group (P < .001). Participants in the TCRT group had a significant decrease in the Timed Up and Go Test from 7.1 seconds (SD = 1.7) at pretest to 6.6 seconds (SD = 2.0) at posttest.33 In addition, the TCRT group showed a 17.6% improvement in dynamic balance, F1,21 = 79.3, η2 = 0.8, in older adults aged 60 to 80 years over a 12-week period.36 A further 3 studies35,36,38 found increased functional mobility in the TCRT group compared with nonexercise or preoperative education groups. In addition, Lin et al33 was able to achieve improvement in the flexibility of lower extremities measured by the Chair-Sit-and-Reach Test through the TCRT intervention (P < .001) from 4.1 cm (SD = 7.3) at pretest to 9.1 cm (SD = 8.9) at posttest.

In contrast, Wang et al37 failed to show the same positive effects of TCRT on Functional Movement Screen tests. The researchers randomly assigned participants to the TCRT group, traditional Tai Chi group, or nonexercise group. Functional Movement Test measures were taken before the study and after the 6-month intervention. The results indicated no significant between-group differences, whereas improvement on the Functional Movement Screen measures was observed for both the TCRT group and the traditional Tai Chi group after the 6-month intervention period (P < .001).

Effects of TCRT on muscle strength

Four studies22,33,36,38 examined lower limb muscle strength, including knee extension and flexion, ankle dorsiflexion and plantar flexion, and hip flexion. Two randomized controlled trials22,36 assessed the effectiveness of TCRT on lower limb isokinetic muscle strength compared with traditional Tai Chi and nonexercise groups and found improvement on knee extension and flexion as well as ankle dorsiflexion and plantar flexion at an angular velocity of 30° per second or 60° per second. The participants with the weakest lower limb muscle strength showed significant improvement after the TCRT intervention.38 Similarly, a cluster randomized trial33 described an improvement in left hip flexion and knee extension in older adults aged 65 years (P < .001) but failed to show favorable effects on right hip flexion. Participants in the TRCT group had significantly higher left hip flexion from 28.1 lb (SD = 7.2) at baseline to 30.4 lb (SD = 8.7) at week 16. In addition, Lin et al33 examined the effects of TCRT on upper limb muscle strength and reported improvement in both shoulder flexion and elbow flexion between the 2 groups (P < .001). Importantly, increased upper body strength measured by the Arm Curl Test (from 20.3 ± 3.6 at baseline to 22.9 ± 4.2 at week 16)33 and lower body strength measured by the 30-second Chair Stand Test (by 15.3% improvement)36 were observed (P < .001).

Effects of TCRT on lumbar spine bone mass

Wang et al34 examined the effects of TCRT versus traditional Tai Chi and a nonexercise group on bone mass in healthy postmenopausal women. Bone mineral density (BMD) was measured at the L2-L4 lumbar spine region, femoral neck, and Ward triangle with dual-energy x-ray absorptiometry at baseline and at the end of the 12-month intervention. Participants in the intervention group attended simplified Tai Chi resistance training (consisting of 4 Chen-style Tai Chi actions, incorporated with resistance training in the last module) 4 times per week for 60 minutes. After 12 months, no significant differences in BMD were found between the 3 groups, with a nonsignificant trend for higher lumbar spine BMD in the TCRT group (P = .06), with 1.1 ± 0.2 g/cm2 in the TCRT group, 1.0 ± 0.2 g/cm2 in the Tai Chi group, and 1.0 ± 0.1 g/cm2 in the nonexercise group. However, BMD at the lumbar spine had increased in the TCRT group compared with baseline (1.1 ± 0.2 g/cm2 vs 1.1 ± 0.2 g/cm2; P = .01)

DISCUSSION

To maintain optimal health and prevent falls in an aging population, it is important for older adults to explore a healthy and suitable exercise in their daily activities in order to improve physical function. The existing evidence supports the effectiveness of TCRT programs for improving mobility, balance, upper and lower extremity muscle strength, and exercise tolerance in adults aged 50 years and older. Previous studies suggest that Tai Chi or resistance training programs are meaningful interventions for older adults suffering from anxiety, depression, and other mental health issues.20,40–42 Resistance training can improve mental health through a complex network of neurophysiological adaptations and these directly and indirectly affect mental health processes.20 Although there may be an association between TCRT programs and mental health in older adults, there is no study that specifically explores the effects of TCRT on mental health.

Studies found that physical activity had a positive association with HRQOL and fear of falling in older adults.43,44 Both Tai Chi and resistance training were independently related to positive changes in HRQOL and fear of falling in older adults.45–48 One study also found that combining Tai Chi and resistance training and followed with educational programs could reduce the rate of falling and the fear of falling in community-dwelling older adults.49 None of the reviewed studies examined the effects of TCRT on HRQOL or fear of falling in adults aged 55 years and older.

Overall, there is good evidence that TCRT is effective for balance and mobility in adults aged 50 years and older. Studies found that Tai Chi or resistance training programs were effective evidence-based approaches to improving balance and mobility in older adults.24,48,50,51 Therefore, our findings are consistent with previous studies suggesting that TCRT is beneficial for increasing balance and mobility in older adults. There is also strong evidence that TCRT is beneficial for enhancing lower extremity muscle strength. For instance, weighted Tai Chi (wearing a weighted vest)22 and TCRT (targeting the lower extremities and postural muscles)36 can significantly improve lower extremity muscle strength compared with traditional Tai Chi and nonexercise. The greater increase in lower body strength is more likely due to the characteristic of Tai Chi movement and resistance training. Tai Chi consists of a series of slow movements involving turning, moving forward, shifting weight, and bending.52 Resistance training has an impact on increasing metabolite, which influences cell swelling and muscle adaptation.53 Previous studies have found that resistance training increased upper extremity muscle strength.54,55 This systematic review provides further evidence that TCRT can greatly improve upper extremity muscle strength compared with nonexercise in community-dwelling older adults.33 However, it is important for future studies to evaluate whether the TCRT program can have greater effects on upper extremity muscle strength than Tai Chi exercise only.

The TCRT program failed to significantly improve the Functional Movement Screen scores compared with either the Tai Chi group or the nonexercise group.37 The Functional Movement Screen has been validated as a form of functional movement measurement in young and active populations.56,57 However, 1 study58 indicated that feasibility of the Functional Movement Screen declines with increased age and decreased activity. As a result, the Functional Movement Screen might not be the most appropriate measurement tool to assess physical function in older adults. An alternative physical function measurement might be considered for older populations in future studies.

There were a number of research design concerns raised by the 7 included studies. For example, 6 studies were open to results bias due to the lack of an intention-to-treat analysis, which can result in the generation of false-positive results.59 One study applied an intention-to-treat analysis and found nonsignificant intergroup differences in the Functional Movement Screen tests.37 All 7 studies were open to selection bias due to nonblinding of participants. In addition, the TCRT dose (ie, frequency, duration, and intensity) varied greatly among 6 studies, which is likely to pose different effects on the reported study outcomes. One study did not indicate the specific training sessions' frequency and duration.38 Moreover, participants' adherence to the exercise is an important factor for achieving effects and is associated to the intervention protocols (eg, session time and session location) and personal factors (eg, health status, family support, and psychological factor).60 However, only 1 of the included studies reported study adherence. A better understanding of adherence to the TCRT interventions may inform future interventions and facilitate the implementation of exercise interventions in older adults.

In terms of the safety of Tai Chi and resistance training, none of the studies reviewed reported any adverse event. It appears that Tai Chi is safe for older adults based on a previous review of a Tai Chi intervention.61 However, resistance training carries a risk of muscle injury, in particular, in older adults with a certain degree of muscle weakness.62 Two possible reasons for the lack of observed adverse events include the following. (1) Safe levels of resistance—resistance levels of the Thera-bands were chosen according to participants' ratings of perceived exertion at a level between 12 and 14 (slightly difficult).33 Zhuang et al36 used participants' body weight as mechanical stress and required no specific equipment to perform; and (2) preparation—warm-up and cooldown routines were practiced before and after TCRT.

In terms of the study country, Mainland China, Taiwan, and Canada were represented in the reported studies, although studies have been conducted to explore the individual benefits of Tai Chi or resistance training in older adults in Australia,63 Germany,64 and Japan.65 None of these existing studies has considered combined TCRT in older adults in areas outside China, Taiwan, and Canada.

This article is the first study to systematically review the effect of combined Tai Chi and resistance training on health outcomes for adults aged 50 years and older. There are, however, some limitations. Trials reported in languages other than English were not included. Nonetheless, we searched all major international scientific databases to maximize our coverage of English written articles.

CONCLUSIONS

Positive results were obtained in this systematic review, and the evidence for the effect of TCRT on physical function and muscle strength of adults aged 50 years and older has been highlighted. However, due to the small number of trials, further research is needed to confirm these findings. The benefits of a TCRT program on mental health outcomes (eg, stress, depression), HRQOL, pain, and age-related impairment should be examined in the same demographic. Future studies with high-quality designs (ie, randomized assignment, appropriately designed TCRT program, participant blinding, assessor blinding, and therapist blinding) should be applied to investigate the long-term effects of TCRT on both mental health and physical function in adults aged 50 years and older.

REFERENCES

1. Holmes J, Powell-Griner E, Lethbridge-Cejku M, Heyman K. Aging differently: physical limitations among adults aged 50 years and over: United States, 2001-2007. NCHS Data Brief. 2009;20(1):1–8.
2. Painter JA, Elliott SJ, Hudson S. Falls in community-dwelling adults aged 50 years and older prevalence and contributing factors. J Allied Health. 2009;38(4):201–207.
3. World Health Organization. Mental health and older adults. http://www.who.int/mediacentre/factsheets/fs381/en/. Accessed December 12, 2017.
4. Landi F, Calvani R, Tosato M, et al. Age-related variations of muscle mass, strength, and physical performance in community-dwellers: results from the Milan EXPO survey. J Am Med Dir Assoc. 2017;18(1):88.e17–88.e24.
5. Turusheva A, Frolova E, Hegendoerfer E, Degryse JM. Predictors of short-term mortality, cognitive and physical decline in older adults in northwest Russia: a population-based prospective cohort study. Aging Clin Exp Res. 2017;29(4):665–673.
6. Ciorba A, Bianchini C, Pelucchi S, Pastore A. The impact of hearing loss on the quality of life of elderly adults. Clin Interv Aging. 2012;7:159–163.
7. Sinn N, Milte CM, Street SJ, et al. Effects of n-3 fatty acids, EPA v. DHA, on depressive symptoms, quality of life, memory and executive function in older adults with mild cognitive impairment: a 6-month randomised controlled trial. Br J Nutr. 2012;107(11):1682–1693.
8. Chang YK, Pan CY, Chen FT, Tsai CL, Huang CC. Effect of resistance-exercise training on cognitive function in healthy older adults: a review. J Aging Phys Act. 2012;20(4):497–517.
9. Yu W, An C, Kang H. Effects of resistance exercise using Thera-band on balance of elderly adults: a randomized controlled trial. J Phys Ther Sci. 2013;25(11):1471–1473.
10. Chang YC, Lu MC, Hu IH, Wu WI, Hu SC. Effects of different amounts of exercise on preventing depressive symptoms in community-dwelling older adults: a prospective cohort study in Taiwan. BMJ Open. 2017;7(4):e014256. doi:10.1136/bmjopen-2016-014256.
11. Chang YC, Wang JD, Chen HC, Hu SC. Aerobic-synergized exercises may improve fall-related physical fitness in older adults. J Sports Med Phys Fitness. 2017;57(5):660–669.
12. Schleicher MM, Wedam L, Wu G. Review of Tai Chi as an effective exercise on falls prevention in elderly. Res Sports Med. 2012;20(1):37–58.
13. Chang Y-K, Nien Y-H, Chen A-G, Yan J. Tai Ji Quan, the brain, and cognition in older adults. J Sport Health Sci. 2014;3(1):36–42.
14. Baker JH. Tai Chi for knee osteoarthritis. Integrative Med Alert. 2017;20(5):49–52.
15. Liu X, Vitetta L, Kostner K, et al. The effects of Tai Chi in centrally obese adults with depression symptoms. Evid Based Complement Alternat Med. 2015;2015:879712. doi: 10.1155/2015/879712.
16. Sharma M, Haider T. Tai Chi as an alternative and complimentary therapy for anxiety: a systematic review. J Evid Based Complementary Altern Med. 2015;20(2):143–153.
17. You T, Ogawa EF, Thapa S, et al. Tai Chi for older adults with chronic multisite pain: a randomized controlled pilot study. Aging Clin Exp Res. 2018;30(11):1335–1343.
18. Liu CJ, Latham NK. Progressive resistance strength training for improving physical function in older adults. Cochrane Database Syst Rev. 2009;(3):Cd002759. doi:10.1002/14651858.CD002759.pub2.
19. Straight CR, Lindheimer JB, Brady AO, Dishman RK, Evans EM. Effects of resistance training on lower-extremity muscle power in middle-aged and older adults: a systematic review and meta-analysis of randomized controlled trials. Sports Med. 2015;46(3):353–364.
20. O'Connor PJ, Herring MP, Caravalho A. Mental health benefits of strength training in adults. Am J Lifestyle Med. 2010;4(5):377–396.
21. Fleck SJ, Kraemer W. Designing Resistance Training Programs, 4E. Champaign, IL: Human Kinetics; 2014.
22. Su Z, Zhao J, Wang N, Chen Y, Guo Y, Tian Y. Effects of weighted Tai Chi on leg strength of older adults. J Am Geriatr Soc. 2015;63(10): 2208–2210.
23. Hu YN, Chung YJ, Yu HK, Chen YC, Tsai CT, Hu GC. Effect of Tai Chi exercise on fall prevention in older adults: systematic review and meta-analysis of randomized controlled trials. Int J Gerontol. 2016;10(3):131–136.
24. Eckardt N. Lower-extremity resistance training on unstable surfaces improves proxies of muscle strength, power and balance in healthy older adults: a randomised control trial. BMC Geriatr. 2016;16(1):1–15.
25. Nelson ME, Rejeski WJ, Blair SN, et al. Physical activity and public health in older adults: recommendation from the American College of Sports Medicine and the American Heart Association. Med Sci Sports Exerc. 2007;39(8):1435–1445.
26. Seguin R, Lamonte M, Tinker L, et al. Sedentary behavior and physical function decline in older women: Findings from the Women's Health Initiative. J Aging Res. 2012;2012:271589. doi:10.1155/2012/271589.
27. Lazenbatt A, Devaney J, Gildea A. Older women living and coping with domestic violence. Community Pract. 2013;86(2):28–32.
28. Sansoni JE. Health Outcomes: An Overview From an Australian Perspective. New South Wales, Australia: University of Wollongong; 2016.
29. Moher D, Shamseer L, Clarke M, et al. Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015 statement. Syst Rev. 2015;4(1):1. doi:10.1186/2046-4053-4-1.
30. da Costa Santos CM, de Mattos Pimenta CA, Nobre MR. The PICO strategy for the research question construction and evidence search. Rev Lat Am Enfermagem. 2007;15(3):508–511.
31. McHugh ML. Interrater reliability: the kappa statistic. Biochem Med. 2012;22(3):276–282.
32. de Morton NA. The PEDro Scale is a valid measure of the methodological quality of clinical trials: a demographic study. Aust J Physiother. 2009;55(2):129–133.
33. Lin SF, Sung HC, Li TL, et al. The effects of Tai-Chi in conjunction with Thera-band resistance exercise on functional fitness and muscle strength among community-based older people. J Clin Nurs. 2015;24(9-10):1357–1366.
34. Wang H, Yu B, Chen W, Lu Y, Yu D. Simplified Tai Chi resistance training versus traditional Tai Chi in slowing bone loss in postmenopausal women. Evid Based Complement Alternat Med. 2015;2015:379451. doi:10.1155/2015/379451.
35. Zeng R, Lin J, Wu S, et al. A randomized controlled trial: preoperative home-based combined Tai Chi and strength training (TCST) to improve balance and aerobic capacity in patients with total hip arthroplasty (THA). Arch Gerontol Geriatr. 2015;60(2):265–271.
36. Zhuang J, Huang L, Wu Y, Zhang Y. The effectiveness of a combined exercise intervention on physical fitness factors related to falls in community-dwelling older adults. Clin Interv Aging. 2014;9:131–140.
37. Wang H, Wei A, Lu Y, et al. Simplified Tai Chi program training versus traditional Tai Chi on the Functional Movement Screening in older adults. Evid Based Complement Alternat Med. 2016;2016:5867810. doi:10.1155/2016/5867810.
38. Robitaille Y, Laforest S, Fournier M, et al. Moving forward in fall prevention: an intervention to improve balance among older adults in real-world settings. Am J Public Health. 2005;95(11):2049–2056.
39. Meier W, Mizner RL, Marcus RL, Dibble LE, Peters C, Lastayo PC. Total knee arthroplasty: muscle impairments, functional limitations, and recommended rehabilitation approaches. J Orthop Sports Phys Ther. 2008;38(5):246–256.
40. Song QH, Shen GQ, Xu RM, et al. Effect of Tai Chi exercise on the physical and mental health of the elder patients suffered from anxiety disorder. Int J Physiol Pathophysiol Pharmacol. 2014;6(1):55–60.
41. Wang C, Bannuru R, Ramel J, Kupelnick B, Scott T, Schmid CH. Tai Chi on psychological well-being: systematic review and meta-analysis. BMC Complement Altern Med. 2010;10(1):23–39.
42. Sims J, Galea M, Taylor N, et al. Regenerate: assessing the feasibility of a strength‐training program to enhance the physical and mental health of chronic post stroke patients with depression. Int J Geriatr Psychiatry. 2009;24(1):76–83.
43. Vasiliadis HM, Belanger MF. The prospective and concurrent effect of exercise on health related quality of life in older adults over a 3 year period. Health Qual Life Outcomes. 2018;16(1):15–23.
44. Sales M, Levinger P, Polman R. Relationships between self perceptions and physical activity behaviour, fear of falling, and physical function among older adults. Eur Rev Aging Phys Act. 2017;14(1):17–27.
45. Sillanpaa E, Hakkinen K, Holviala J, Hakkinen A. Combined strength and endurance training improves health-related quality of life in healthy middle-aged and older adults. Int J Sports Med. 2012;33(12):981–986.
46. Sun J, Buys N, Jayasinghe R. Effects of community-based meditative Tai Chi programme on improving quality of life, physical and mental health in chronic heart-failure participants. Aging Ment Health. 2014;18(3): 289–295.
47. Logghe IH, Verhagen AP, Rademaker AC, et al. The effects of Tai Chi on fall prevention, fear of falling and balance in older people: a meta-analysis. Prev Med. 2010;51(3-4):222–227.
48. Prata MG, Scheicher ME. Effects of strength and balance training on the mobility, fear of falling and grip strength of elderly female fallers. J Bodyw Mov Ther. 2015;19(4):646–650.
49. Filiatrault J, Gauvin L, Richard L, et al. Impact of a multifaceted community-based falls prevention program on balance-related psychologic factors. Arch Phys Med Rehabil. 2008;89(10):1948–1957.
50. Ory MG, Smith ML, Parker EM, et al. Fall prevention in community settings: results from implementing Tai Chi: Moving for Better Balance in three States. Front Public Health. 2015;2:258. doi:10.3389/fpubh.2014.00258.
51. Hackney ME, Wolf SL. Impact of Tai Chi Chu'an practice on balance and mobility in older adults: an integrative review of 20 years of research. J Geriatr Phys Ther. 2014;37(3):127–135.
52. Klein P, Picard G, Baumgarden J, Schneider R. Meditative movement, energetic, and physical analyses of three Qigong exercises: unification of Eastern and Western mechanistic exercise theory. Medicines (Basel). 2017;4(4):69–89.
53. de Freitas MC, Gerosa-Neto J, Zanchi NE, Lira FS, Rossi FE. Role of metabolic stress for enhancing muscle adaptations: practical applications. World J Methodol. 2017;7(2):46–54.
54. Turbanski S, Schmidtbleicher D. Effects of heavy resistance training on strength and power in upper extremities in wheelchair athletes. J Strength Cond Res. 2010;24(1):8–16.
55. de Franca HS, Branco PA, Guedes Junior DP, Gentil P, Steele J, Teixeira CV. The effects of adding single-joint exercises to a multi-joint exercise resistance training program on upper body muscle strength and size in trained men. Appl Physiol Nutr Metab. 2015;40(8):822–826.
56. Teyhen DS, Shaffer SW, Lorenson CL, et al. The Functional Movement Screen: a reliability study. J Orthop Sports Phys Ther. 2012;42(6): 530–540.
57. Minick KI, Kiesel KB, Burton L, Taylor A, Plisky P, Butler RJ. Interrater reliability of the Functional Movement Screen. J Strength Cond Res. 2010; 24(2):479–486.
58. Mitchell UH, Johnson AW, Vehrs PR, Feland JB, Hilton SC. Performance on the Functional Movement Screen in older active adults. J Sport Health Sci. 2016;5(1):119–125.
59. Gupta SK. Intention-to-treat concept: a review. Perspect Clin Res. 2011;2(3):109–112.
60. Picorelli AM, Pereira LS, Pereira DS, Felicio D, Sherrington C. Adherence to exercise programs for older people is influenced by program characteristics and personal factors: a systematic review. J Physiother. 2014;60(3): 151–156.
61. Wang Y, Shan W, Li Q, Yang N, Shan W. Tai Chi exercise for the quality of life in a perimenopausal women organization: a systematic review. Worldviews Evid Based Nurs. 2017;14(4):294–305.
62. Sousa N, Mendes R, Monteiro G, Abrantes C. Progressive resistance strength training and the related injuries in older adults: the susceptibility of the shoulder. Aging Clin Exp Res. 2014;26(3):235–240.
63. Saravanakumar P, Higgins IJ, van der Riet PJ, Marquez J, Sibbritt D. The influence of Tai Chi and yoga on balance and falls in a residential care setting: a randomised controlled trial. Contemp Nurse. 2015;48(1):76–87.
64. Burschka JM, Keune PM, Oy UH, Oschmann P, Kuhn P. Mindfulness-based interventions in multiple sclerosis: beneficial effects of Tai Chi on balance, coordination, fatigue and depression. BMC Neurol. 2014;14(1):165–174.
65. Hirase T, Inokuchi S, Matsusaka N, Nakahara K, Okita M. Effects of a resistance training program performed with an interocclusal splint for community-dwelling older adults: a randomized controlled trial. J Phys Ther Sci. 2016;28(5):1499–1504.
Appendix 1. - Search Strategy
PubMed
#1. (((((((((((Tai Ji[MeSH Terms]) OR Tai-Ji) OR Chi, Tai) OR Ji Quan, Tai) OR Quan, Tai ji) OR Taiji) OR Tai Chi) OR Tai Ji Quan) OR Taijiquan) OR T'ai Chi) OR Tai Chi Quan) OR Shadow Boxing)
#2. (((((resistance training[MeSH Terms]) OR elastic band) OR Thera-band) OR strength training) OR strengthening program) OR weight training)
#3. ((((((((((adults[MeSH Terms]) OR older people) OR older person) OR old people) OR old person) OR older adults) OR elderly) OR ageing population) OR older women) OR Postmenopausal Women) OR older men)
#4. #1 AND #2 AND #3
Scopus
1. (TITLE-ABS-KEY (tai AND ji) OR TITLE-ABS-KEY (tai-ji) OR TITLE-ABS-KEY (chi, AND tai) OR TITLE-ABS-KEY (ji AND quan, AND tai) OR TITLE-ABS-KEY (quan, AND tai AND ji) OR TITLE-ABS-KEY (taiji) OR TITLE-ABS-KEY (tai AND chi) OR TITLE-ABS-KEY (tai AND ji AND quan) OR TITLE-ABS-KEY (taijiquan) OR TITLE-ABS-KEY (t'ai AND chi) OR TITLE-ABS-KEY (tai AND chi AND quan) OR TITLE-ABS-KEY (shadow AND boxing)
2. (TITLE-ABS-KEY (resistance AND training) OR TITLE-ABS-KEY (elastic AND band) OR TITLE-ABS-KEY (thera-band) OR TITLE-ABS-KEY (resistance AND training) OR TITLE-ABS-KEY (strength AND training) OR TITLE-ABS-KEY (strengthening AND program) OR TITLE-ABS-KEY (weight AND training)
3. (TITLE-ABS-KEY (older AND people) OR TITLE-ABS-KEY (older AND person) OR TITLE-ABS-KEY (old AND people) OR TITLE-ABS-KEY (old AND person) OR TITLE-ABS-KEY (older AND adults) OR TITLE-ABS-KEY (elderly) OR TITLE-ABS-KEY (ageing AND population) OR TITLE-ABS-KEY (older AND women) OR TITLE-ABS-KEY (postmenopausal AND women) OR TITLE-ABS-KEY (older AND men)
4. #1 AND #2 AND #3
Web of Science
1. TOPIC: (Tai Ji) OR TOPIC: (Tai-Ji) OR TOPIC: (Chi, Tai) OR TOPIC: (Ji Quan, Tai) OR TOPIC: (Quan, Tai ji) OR TOPIC: (Taiji) OR TOPIC: (Tai Chi) OR TOPIC: (Tai Ji Quan) OR TOPIC: (Taijiquan) OR TOPIC: (T'ai Chi) OR TOPIC: (Tai Chi Quan) OR TOPIC: (Shadow Boxing)
Indexes=SCI-EXPANDED, SSCI, A&HCI, CPCI-S, CPCI-SSH, BKCI-S, BKCI-SSH, ESCI, CCR-EXPANDED, IC
2 TOPIC: (resistance training) OR TOPIC: (elastic band) OR TOPIC: (Thera-band) OR TOPIC: (strength training) OR TOPIC: (strengthening program) OR TOPIC: (weight training)
Indexes=SCI-EXPANDED, SSCI, A&HCI, CPCI-S, CPCI-SSH, BKCI-S, BKCI-SSH, ESCI, CCR-EXPANDED, IC
3. TOPIC: (older people) OR TOPIC: (older person) OR TOPIC: (old people) OR TOPIC: (old person) OR TOPIC: (older adults) OR TOPIC: (elderly) OR TOPIC: (ageing population) OR TOPIC: (older women) OR TOPIC: (Postmenopausal Women) OR TOPIC: (older men)
Indexes=SCI-EXPANDED, SSCI, A&HCI, CPCI-S, CPCI-SSH, BKCI-S, BKCI-SSH, ESCI, CCR-EXPANDED, IC
4. #1 AND #2 AND #3
CINAHL
#1. TX Tai Ji OR TX Tai-Ji OR TX Chi, Tai OR TX Ji Quan, Tai OR TX Quan, Tai ji OR TX Taiji OR TX Tai Chi OR TX Tai Ji Quan OR TX Taijiquan OR TX T'ai Chi OR TX Tai Chi Quan OR TX Shadow Boxing
#2. TX resistance training OR TX elastic band OR TX Thera-band OR TX strength training OR TX strengthening program OR TX weight training
#3. TX older people OR TX older person OR TX old people OR TX old person OR TX older adults OR TX elderly OR TX ageing population OR TX older women OR TX Postmenopausal Women OR TX older
#4. #1 AND #2 AND #3
MEDLINE
#1. TX Tai Ji OR TX Tai-Ji OR TX Chi, Tai OR TX Ji Quan, Tai OR TX Quan, Tai ji OR TX Taiji OR TX Tai Chi OR TX Tai Ji Quan OR TX Taijiquan OR TX T'ai Chi OR TX Tai Chi Quan OR TX Shadow Boxing
#2. TX resistance training OR TX elastic band OR TX Thera-band OR TX strength training OR TX strengthening program OR TX weight training
#3. TX older people OR TX older person OR TX old people OR TX old person OR TX older adults OR TX elderly OR TX ageing population OR TX older women OR TX Postmenopausal Women OR TX older
#4. #1 AND #2 AND #3
PEDro
Tai Chi, resistance, older adults
Cochrane
Tai Ji or Tai-Ji or Chi, Tai or Ji Quan, Tai or Quan, Tai ji or Taiji or Tai Chi or Tai Ji Quan or Taijiquan or T'ai Chi or Tai Chi Quan or Shadow Boxing in Title, Abstract, Keywords and elastic band or Thera-band or resistance training or strength training or strengthening program or weight training in Title, Abstract, Keywords and older people or older person or old people or old person or older adults or elderly or ageing population or older women or Postmenopausal Women or older men in Trials in Title, Abstract, Keywords in Trials'

Keywords:

older adults; physical function; resistance training; Tai Chi

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