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Decrease of dual-task (DT) ability is known to be one of the risk factors for falls. We developed a new game concept, Dual-Task Tai Chi (DTTC), using Microsoft’s motion-capture device Kinect, and demonstrated that the DTTC test can quantitatively evaluate various functions that are known risk factors for falling in elderly adults. Moreover, DT training has been attracting attention as a way to improve balance and DT ability. However, only a few studies have reported that it improves cognitive performance.
The purpose of this study was to demonstrate whether or not a 12-week program of DTTC training would effectively improve cognitive functions.
This study examined cognitive functions in community-dwelling older adults before and after 12 weeks of DTTC training (training group [TG]) or standardized training (control group [CG]). Primary end points were based on the difference in cognitive functions between the TG and the CG. Cognitive functions were evaluated using the trail-making test (part A and part B) and verbal fluency test.
A total of 41 elderly individuals (TG: n=26, CG: n=15) participated in this study and their cognitive functions were assessed before and after DTTC training. Significant differences were observed between the two groups with significant group × time interactions for the executive cognitive function measure, the delta-trail-making test (part B−part A;
The results suggest that DTTC training is effective for improving executive cognitive functions.
Japan Medical Association Clinical Trial Registration Number: JMA-IIA00092; https://dbcentre3.jmacct.med.or.jp/jmactr/App/JMACTRS06/JMACTRS06.aspx?seqno=2682 (Archived by WebCite at http://www.webcitation.org/6NRtOkZFh).
Cognitive impairment among elderly individuals is a serious issue in many countries. Many investigators have developed different cognitive function training methods as countermeasures to prevent cognitive impairment and have reported their effects [
Recently, dual-task (DT) ability, or the performance of simultaneous motor and cognitive tasks, has been receiving considerable attention [
With a focus on DT, we developed a new concept called the Dual-Task Tai Chi (DTTC) test [
Several investigators have reported the effects of DT training on balance, mobility, walking, and DT ability [
Community-dwelling elderly subjects (n=48) participated in this study. The subjects were recruited through an advertisement in the local press. The following selection criteria were used: age ≥65 years, community dwelling, independent ambulation, willingness to participate in the measurement of physical fitness, and minimal hearing and vision impairment. Exclusion criteria were as follows: inability to complete the tasks because of reduced cognitive functions, evaluated by Rapid Dementia Screening Test [
The DTTC test [
To begin with, the user stands 3 m in front of the Kinect sensor with his or her right foot in front of the sensor (
Reach a digit you need to use with your right hand to fill a blank you want to answer.
Step 50 cm laterally, with your left leg, to grip the digit in your right hand.
Select the blank you want to answer with your left hand, and move your right hand to your left one.
View of the Dual-Task Tai Chi (DTTC) test.
All subjects participated in group training sessions lasting 75-80 minutes once a week for 12 weeks. The participants were divided into two training groups according to their participation in the exercise class: (1) the control group (CG), 75-minute standardized training, and (2) the training group (TG), 5-minute DTTC training, in addition to the standardized training [
The exercise classes were individualized for each group and were supervised by physical therapists. Each exercise class used a standardized format that included 15 minutes of moderate-intensity aerobic exercise, 15 minutes of progressive strength training, 10 minutes of flexibility and balance exercises, and 10 minutes of cool-down activities, followed by exercises known to improve muscle strength and balance [
The participants in the TG were additionally asked to solve DTTC problems and mirror-reversed DTTC problems, alternately, as many times possible in 5 minutes.
All participants underwent evaluation upon entry into the study (pre-intervention) and at the end of the study (post-intervention), using the results of 2 cognitive performance tests.
Cognitive functions were evaluated using the trail-making test (TMT) [
The VFT has a letter fluency component and a category fluency component. Participants were asked to think of as many animal names as possible in 1 minute (category fluency). Verbal fluency is an evaluation of expressive language ability and executive functions. The score was the number of successful words (except for some proper nouns).
We compared baseline characteristics between the participants in each group to examine the comparability between the 2 groups using Student’s
Data were entered and analyzed using the Statistical Package for the Social Sciences (Windows version 20.0, SPSS Inc., Chicago, IL, USA). For all analyses,
A total of 41 of the 48 selected subjects (85.4%) completed the study protocols and returned for their exit interviews and final testing (TG: n=26, CG: n=15). The participants’ baseline data did not differ significantly between the two groups. Thus, the groups were comparable and well matched with regard to their baseline characteristics.
During the 12-week intervention phase, 10 exercise sessions were scheduled and all took place. Excluding the 4 participants who dropped out, the TG subjects had an overall attendance rate of 82% and the CG subjects had an overall attendance rate of 81% over the 12 weeks. No health problems, including cardiovascular or musculoskeletal complications, occurred during training sessions or testing. Moreover, almost all participants seemed to have enjoyed the DTTC training. They shared many positive opinions after each session and seemed to look forward to playing DTTC once a week.
Pre- and post-intervention group statistics and group × time interactions are shown in
Outcome measures by group at pre- and post-intervention.
Measures | Pre-intervention, |
Post-intervention, |
Group × Time |
Degrees of freedom |
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TGb | 11.96 (3.55) | 12.04 (3.26) | 0.09 | 1,38 | .76 |
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CGc | 11.38 (4.21) | 11.38 (4.07) |
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TG | 71.6 (23.8) | 68.4 (19.9) | 0.51 | 1,38 | .48 |
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CG | 82.2 (27.1) | 70.0 (15.5) |
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TG | 120.3 (55.1) | 110.4 (39.2) | 2.73 | 1,38 | .11 |
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CG | 131.8 (62.6) | 134.9 (61.1) |
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TG | 48.8 (43.9) | 42.2 (29.0) | 4.94 | 1,36 | .03 |
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CG | 49.5 (51.8) | 64.9 (54.7) |
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aVFT: verbal fluency test
bTG: training group
cCG: control group
dTMT: trail-making test
The delta-TMT score was significantly improved after DTTC training. The results suggested that DTTC training was effective in improving executive cognitive functions. In our unpublished data, DTTC training was useful for improving balance ability and mobility among elderly people [
Conversely, the TMT-A and -B scores were not significantly improved. In the TMT-A, both groups improved similarly. On the other hand, in the TMT-B, only the TG had a tendency to improve the score, while CG showed little change. That is why the score of delta-TMT in CG increased and in TG decreased. The TMT-A and -B are used to assess visual scanning, cognitive flexibility, and executive functions [
Previous studies reported that other “exergames,” based on Nintendo Wii Fit (Nintendo, Kyoto, Japan) or other devices, improved balance and leg muscle functions [
There are several limitations to this study. First, the intervention effects in this study were not due solely to the DTTC training. That means the rhythmic stepping exercise involving cognitive ability in both groups also improves cognitive ability. Second, participants in both groups may have had higher motivation and interest in health issues and fall risk minimization than the general elderly population. An investigation into the effects of DTTC training on functions in frail, elderly adults is necessary, in the future.
In this study, the ANCOVA results of delta-TMT reveal that group × time interactions were statistically significant. They suggest that DTTC training is effective at improving executive cognitive functions in particular.
control group
dual task
Dual-Task Tai Chi
training group
trail-making test
verbal fluency test
The authors thank the participants and are grateful to the department staff for helpful advice.
None declared.