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This pilot study examines the effects of Tai Chi on balance, gait and mobility in people with Parkinson disease (PD). Thirty-three people with PD were randomly assigned to either a Tai Chi group or a control group. The Tai Chi group participated in 20 one-hour long training sessions completed within 10–13 weeks; whereas, the control group had two testing sessions between 10 and 13 weeks apart without interposed training. The Tai Chi group improved more than the control group on the Berg Balance Scale, UPDRS, Timed Up and Go, tandem stance test, 6-minute walk, and backward walking. Neither group improved in forward walking or the one leg stance test. All Tai Chi participants reported satisfaction with the program and improvements in well-being. Tai Chi appears to be an appropriate, safe and effective form of exercise for some individuals with mild-moderately severe PD.
Parkinson disease (PD), a progressive neurodegenerative movement disorder that affects more than 1 million people in the United States, causes falls and hip fractures costing approximately $192 million annually1, 2. Strategies to improve balance may help reduce falls and disability from hip fractures. Tai Chi, a martial art that involves slow controlled movement and the maintenance of various postures, may be an effective means of addressing balance problems. Five days of Tai Chi training improved the 50-foot speed walk, the Timed Up and Go and the Functional Reach test6 in 17 people with mild PD. Similarly, 12 Tai Chi sessions enhanced physical aspects of well being and balance in 8 people with PD7. Qi Gong, a martial art similar to Tai Chi, enhanced scores on the UPDRS motor subscale 3 and reduced the rate of progression across a one-year period in PD5. While these studies highlight the feasibility and potential benefits of Tai Chi, none employed a control group.
The purpose of this pilot study is to quantify the effects of Tai Chi on functional mobility, gait and balance in people with mild to moderate PD compared to a matched untreated control group with PD. We hypothesized that TC would result in improvements not seen in the control group.
CONSORT guidelines were followed in the conduct and reporting of this study. This work was approved by the Human Research Protection Office at Washington University in St. Louis (protocol # 06-0280). All participants provided written informed consent prior to participation.
Participants were at least 40 years of age, could stand for 30 minutes, could walk independently for at least 3 meters with or without an assistive device, had Hoehn & Yahr scores ranging from 1.5-3, and each had a diagnosis of idiopathic PD. PD diagnostic criteria were those used for clinically defined “definite PD” based upon published standards8–10. Participants all demonstrated clear benefit from levodopa and were tested on medications. Testing was performed at a standardized time during the medication cycle to reduce the effects of medication-related fluctuations in performance. Participants were excluded if they had: 1) a serious medical problem, or 2) history or evidence of neurological deficit other than PD that could interfere, such as previous stroke or neuromuscular disease. Participants were recruited from the St. Louis community through advertisement at local support groups and local American Parkinson Disease Association community events, as well as through the Washington University Movement Disorders Center. While some participants self-identified, most were directly recruited via telephone.
Thirty-three participants with PD took part in this study. See Table 1 for participant demographics. Participants were randomly assigned to participate either in Tai Chi (TC) or in a Control group. Simple random assignment was performed by the first author using a coin toss. At the start of the study there were 17 TC participants and 16 controls. Note that while the first author was not blinded to group assignment, all participant evaluations were videotaped for scoring by a blinded rater.
The TC participants received structured, progressive lessons from an experienced instructor. They were taught the first and second circles of the Yang Short Style of Cheng Manching. Participants attended twice weekly one hour lessons, completing 20 lessons within 13 weeks. Those in the control group received no intervention.
Assessments of TC participants were conducted the week prior to initiation of training and the week following completion of 20 training sessions. Assessments of Control participants were conducted at the same time interval as the TC participants. All assessments were videotaped and data files were coded for blinded ratings. During each assessment, participants were first evaluated using the Unified Parkinson’s Disease Rating Scale Motor Subscale 3 (UPDRS) 11,12. Balance was evaluated using the Berg Balance Scale (BBS) 13, the tandem stance test (TS), and the one leg stance test (OLS) 14. Functional mobility was assessed using the Timed Up and Go test (TUG) 15,16 and gait was assessed by examining standard forward and backward walking along an instrumented, computerized GAITRite walkway (CIR Systems, Inc., Havertown, PA). Finally, gait endurance was measured using the six minute walk test.
During the post-testing session, TC subjects also completed a questionnaire asking them to rank items on a scale of 1–5 (1 = strongly agree, 2 = somewhat agree, 3 = neither agree nor disagree, 4 = somewhat disagree, 5 = strongly disagree.) Item 1 asked if participants enjoyed participating in Tai Chi and items 2 through 7 asked if participants noted improvement in particular aspects of physical well-being since beginning the Tai Chi classes.
Spatiotemporal features of walking were measured using a 5m instrumented, computerized walkway. Subjects were asked to walk both forward and backward on the walkway at their normal pace, performing three trials in each direction. Results from the three trials of each direction were averaged. The primary variables of interest were gait velocity, stride length, and functional ambulation profile (FAP). The FAP is a single, numerical representation of gait performance17 that is valid, reliable, and can discriminate between people with and without PD when walking at preferred speeds18.
For each individual, pre-test values were subtracted from post-test values to obtain individual change scores. Absolute change scores were compared between groups using independent t-tests when appropriate. Mann Whitney Rank Sum tests were used when data were not normally distributed. A Bonferroni correction was applied to account for the use of multiple tests. Overall significance level was P = 0.05, and each test had a significance cutoff of p ≤ 0.004.
Four participants in TC did not complete the study: one withdrew at week 4 upon being hospitalized for unrelated issues, one withdrew after week 5 citing that the exercise was not sufficiently intense, and two who had transportation issues attended sporadically over the course of the entire study but did not complete the required 20 lessons in 13 weeks. Three controls were unable to complete post-testing during the required time interval due to an ankle injury, a hospitalization, and a death in the family. Thus, in each group there were 13 participants who completed the study. Only data from these 26 individuals were analyzed.
At baseline, the two groups were not significantly different with respect to age, UPDRS scores, H&Y values, or duration of PD. At post-testing, however, several differences in change scores were noted between groups with the TC group showing greater improvement than the Control group in all cases (Table 2). Improvement in Berg Balance scores was significantly greater for the TC than the Control group. The TC group also improved on the UPDRS motor subscale 3, tandem stance, Timed Up & Go, and the six minute walk while the Control group showed little change on these measures. Improved FAP, stride length and velocity for backward walking indicated improved backward walking in the TC but not the Control group. Forward walking and one leg stance did not improve in either group.
In addition to the quantitative changes noted above, TC participants reported that they enjoyed participating and noted improvements in their physical performance. Median and interquartile values are reported for questionnaire responses. Participants reported having enjoyed the class (median = 1( 25%:1.0, 75%: 2.0)), and somewhat agreed with the statements “my balance has improved” (median = 2.0 ( 25%: 1.8, 75%: 3.0)), “my walking has improved” (median = 2.0 (25%: 1.0, 75%:3.0)), “my coordination has improved” (median = 2.0(25%: 2.0, 75%: 3.0)), “my endurance has improved” (median =2.0 (25%: 1.8, 75%: 3.0), and “my mood has improved” (median = 2.0 (25%: 2.0, 75%: 3.0)). Participants neither agreed nor disagreed with the statement “my strength has improved” (median, 3.0 (25%: 2.8, 75%: 3.0).
This pilot study compared changes in functional mobility in people with PD who participated in Tai Chi to a matched control group who received no intervention. The TC group demonstrated improvements in Berg balance scores and TUG performance similar to those reported previously for elderly individuals with and without PD who practiced Qigong or Tai Chi 5,6,19,20. The lack of improvement in one leg stance for the TC group contrasts with a study of more than 100 seniors who participated in Tai Chi three times weekly for three months. They showed improvements of more than 3 seconds in one leg stance time20. The lack of improvement in forward walking in the present study was consistent with a previous study of more than 150 elders without PD who showed no changes in gait velocity after participating in a year of Tai Chi20. However, several other studies have reported improvements in gait with TC, including an improvement of 2.3s in the 50 foot speed walk in persons with PD6. Improved gait performance was also noted in 28 elderly people following 48 weeks of Tai Chi22 and in a group of vestibulopathic participants who practiced Tai Chi for ten weeks23. The lack of effects on one leg stance and gait in our study may be related to the small sample size and short duration of Tai Chi training.
This is the first study to examine six minute walk performance before and after Tai Chi. The improvement noted in the TC group may reflect improved balance. Alternatively, the improvement may reflect increased endurance, as Tai Chi has been shown to reduce systolic blood pressure, total cholesterol, heart rate and low-density lipoprotein cholesterol levels after as little as 10 weeks24,25.
This study has several limitations including small sample size and a short duration of training. Longer training may increase the benefit from Tai Chi. Tj\his is supported by the fact that long-term Tai Chi practitioners exhibit smaller increases in postural sway in the antero-posterior direction in response to perturbation26, an effect not seen in individuals who had practiced Tai Chi for only 3 months27. However, this apparent long term benefit may reflect incorporation bias, as those able to participate in Tai Chi for a longer term may be healthier than those that cannot endure.
To conclude, participants with PD who participated in twice weekly Tai Chi lessons demonstrated improvements in gait, balance and functional mobility. Although this pilot study is limited by a relatively small sample size and short training duration, the results suggest that Tai Chi may be an effective and safe form of exercise for some individuals with mild to moderately severe PD.
We would like to acknowledge Josh Funk, Minna Hong, Ruth Porter, Mike Falvo, Lauren Mehner, Tiffany Chung, Ba Huynh, Jeff Becket, Kyleen Albert, Laura Cohen, Patricia Engel, Callie Chen, Svetlana Kantorovich, Ryan Choi and Marghuretta Bland, for their assistance with this project. We also thank Joel Perlmutter for assitance with revision of this manuscript. A grant from the American Parkinson Disease Association funded this work. The study sponsors played no role in the study design, in the collection, analysis and interpretation of data; in the writing of the manuscript; and in the decision to submit the manuscript for publication.
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