By Min Mao, PhDc; Vicki S. Mercer, PT, PhD; Fuzhong Li, PhD; Michael T. Gross, PT, PhD, FAPTA; Troy Blackburn, PhD, ATC; and Bing Yu, PhD
Tai Chi is an evidence-based fall prevention training for older adults, yet its effective movements remain unclear.
Practicing Tai Chi (TC)—exercise that consists of a series of slow movements performed in semi-squat positions with an emphasis on coordination of whole-body movement and mind—is an effective way to prevent falls in older adults. Previous studies have demonstrated that practicing TC reduced risk of falls in older adults and improved clinical balance and walking measures. In addition, healthy community-dwelling older adults who practiced TC also had reduced center of pressure (COP) displacement and speed during bipedal and unipedal stance compared with older adults who exercised regularly but who did not practice TC. Although TC is an evidence-based fall prevention training for older adults, its effective movements remain unclear, which may limit the practice of TC. The purpose of this study was to compare the effectiveness of TC lower extremity exercise (TC LEE), the 8-form Tai Chi (8-form TC), and a stretching control intervention for improving balance and functional mobility among older adults.
Methods
A total of 102 participants (79 ± 6 years old) were recruited from assisted living facilities for this randomized controlled trial. All participants were randomly assigned to the TC LEE (n = 40), 8-form TC (n = 31), and stretching (n = 31) groups in which they received the respective interventions for 16 weeks. The Berg Balance Scale (BBS), Timed Up and Go (TUG) test, and center of pressure (COP) measurements during quiet stance were collected prior to and following the 16-week interventions. Comparisons on all measurements were conducted among all groups.
TC LEE involved only the lower extremity movements of the 8-form TC, including: (A) Forward Stepping, (B) Backward Stepping, (C) Side Stepping, (D) Single-leg Stepping, (E) Turning Stepping, and (F) Fixing Stepping (Figure 1). The difficulty of the TC LEE movements increased gradually, requiring progressively greater postural control and coordination. The participants were required to perform the TC LEE with their hands together in front of their waists throughout the entire exercise.
The 8-form TC consists of 8 poses selected from the 24-form Tai Chi. The 8 forms were named as: (1) Commencing Form, (2) Repulse Monkey, (3) Grasp Peacock’s Tail, (4) Wave Hands Like Clouds, (5) Fair Lady Works at Shuttles, (6) Golden Cock Stands on One Leg, (7) Brush Knees, and (8) Closing Form (Figure, page 33). Initial movements involved upper extremity movement patterns, such as Commencing Form, which required minimal postural control and whole-body coordination. The difficulty of the movements increased gradually and required more postural control and coordination of the entire body, such as Brush Knees. (See “Biomechanical Analysis of Thoracolumbar Rotation During Tai Chi Movements,” page 33.)
The stretching intervention included light walking, stretching, and relaxing. Each session began with 15 minutes of light walking (60–65% of the maximal heart rate) followed by 30 minutes of stretching of the major muscle groups of the entire body. After the stretching, participants completed 15 minutes of relaxation with deep breathing and meditation.
Results
Significant improvements were found in BBS (P = 0.002), TUG test (P = 0.001), root mean square (RMS) amplitude of COP displacement in the anterior-posterior (P = 0.001) and medial-lateral (P = 0.001) directions, and average COP speed in the anterior-posterior (P = 0.001) and medial-lateral (P = 0.001) directions after training in the TC intervention groups compared with the stretching group. The upper limit of the 95% confidence interval (CI) of differences in change scores on the BBS (-0.8–1.3 points) between the TC LEE group and the 8-form TC group was within equivalence margins (1.8 points), while the upper limit of the 95% CI of differences in change scores on the TUG test (0.1–2.1 s) exceeded the equivalence margin (0.7 s) with the TC LEE group having the larger change scores.
No intervention safety issue was reported (falls, fractures, and joint pain etc. during or after training).
Discussion
Figure 1. Tai Chi lower extremity exercise: A) Forward Stepping, B) Side Stepping, C) Backward Stepping, D) Turning Stepping, E) Single-leg Stepping, and F) Fixing Stepping.
The improvement on the BBS and TUG tests indicates improvements in balance and mobility in older adults. The average BBS scores in TC LEE and 8-form TC groups increased by 2.7 ± 2.3 points and 2.6 ± 2.2 points, respectively, indicating that increases in the BBS in the TC LEE and 8-form TC group after intervention might be marginally meaningful. The TUG test values in TC LEE and 8-form TC groups decreased by 3.2 ± 1.0 s and 2.1 ± 2.4 s, respectively, suggesting the improvements of TUG test after training in both TC groups were meaningful.
Significant reductions in the RMS amplitude of COP displacement and the speed of COP were found in both TC intervention groups compared with the control group after training in this study, which was consistent with previous findings. Collectively, these findings suggest that both of the TC interventions evaluated in this investigation may improve balance and functional mobility in older adults.
TC movements have characteristics that might promote improved balance in older adults, such as slow movements, frequent body weight shifts in various directions, large range of motion of lower extremity joints, and maintenance of a semi-squat position, which require precise neuromuscular control for coordination. Both the 8-form TC and the TC LEE forms include these beneficial characteristics. These characteristics could potentially challenge the balance control of older adults, thereby improving the control of body weight over the base of support and improving the neuromuscular control of the lower extremities. The body weight shifts in the forward, backward, lateral, and diagonal directions mimic movements in daily life for older adults, thus potentially transferring to improved dynamic balance during movement. The combination of these improvements may, therefore, decrease falls risk of older adults.
The results of this study suggest that TC LEE produces similar improvements in the BBS and greater effects on the TUG test compared with the 8-form TC form. One unique characteristic of TC LEE is that it is performed without upper extremity movements, which potentially makes TC LEE movements more challenging to maintain balance. Because upper extremity movements serve an important role in maintaining balance, without assistance from the upper extremities, practitioners might need greater momentum from the lower extremities in moving the trunk toward the direction of shifts in body weight and may need more precise neuromuscular control of their lower extremities to generate enough momentum for shifts in body weight, but not too much to cause a loss of balance. Consequently, the TC LEE might require more effort to maintain balance during training sessions. These findings might suggest that the lack of upper extremity movements in the TC LEE intervention might produce greater improvements in balance in older adults.
Because TC LEE is practiced without arm movements, it might require less cognitive resources, and it may be easier to learn for older TC beginners, frail older adults, older adults with decreased cognitive capabilities, and older adults with upper extremity injuries who would like to improve their balance and prevent falls. Practicing TC LEE could improve balance control and functional mobility, which can serve as a new option for clinicians to treat patients with increased risk of falls. Clinicians can teach patients the entire set of TC LEE movements, or they can select some of the stepping movements of interest for patients to practice. In addition, clinicians can combine TC LEE with existing fall prevention programs to provide effective, individualized, and multiple interventions for patients. Furthermore, TC LEE could be applied in different settings, such as, clinics, assisted living facilities, nursing homes, and communities.
Conclusion
In this study, the authors developed the TC LEE, which was performed with no upper extremity movements and with movement patterns that involved frequent shifts in body weight and frequent changes in stepping direction. TC LEE may simulate balance challenges encountered in daily activities by older adults. Based on the results of this study, TC LEE could be used as an effective balance training exercise for older adults and may have a greater effect than the 8-form TC on improving functional mobility as measured by the TUG test.
Authors
Min Mao is a PhD candidate in the Division of Physical Therapy, Department of Health Sciences, University of North Carolina, Chapel Hill, and an assistant research professor in the Department of Rehabilitation Nursing at Shandong University, Jinan, Shandong, China.
Vicki S. Mercer, PT, PhD, is a professor with the Division of Physical Therapy, Department of Health Sciences, University of North Carolina at Chapel Hill.
Fuzhong Li, PhD, is a senior scientist with the Oregon Research Institute, Eugene.
Michael T. Gross, PT, PhD, FAPTA, is a professor with the Division of Physical Therapy, Department of Health Sciences, University of North Carolina at Chapel Hill.
Troy Blackburn, PhD, ATC, is chair and professor, Exercise and Sport Science, and an associate director, MOTION Science Institute, Department of Exercise and Sport Science, University of North Carolina at Chapel Hill.
Bing Yu, PhD, is a professor, Fellow International Society of Biomechanics, Division of Physical Therapy, Department of Health Sciences, University of North Carolina at Chapel Hill.
This article has been excerpted from “The effect of Tai Chi lower extremity exercise on the balance control of older adults in assistant living communities. BMC Complement Med Ther. 2024;24(1):112. doi: 10.1186/s12906-024-04382-9. Editing has occurred, including the renumbering or removal of tables, and references have been removed for brevity. Use is per CC Attribution 4.0 International License.
Biomechanical Analysis of Thoracolumbar Rotation During Tai Chi Movements
Figure. Movements of the Peking style routine. 1) Beginning; 2) Part the wild horse’s mane (left and right); 3) White crane spreads its wings; 4) Brush knee and step forward (left and right);
5) Playing the lute; 6) Step back and repulse monkey (left and right); 7) Grasp the sparrow’s tail (left); 8) Grasp the sparrow’s tail (right); 9) Single whip; 10) Wave hand in the clouds; 11) Single whip; 12) High pat on horse; 13) Right heel kick; 14) Strike to ears with both fists; 15) Left heel kick; 16) Lower body and stand on one leg (left); 17) Lower body and stand on one leg (right);
18) Fair lady weaves with shuttle (right and left); 19) Pick up the needle from the sea bottom; 20) Fan back; 21) Turn body, Deflect, Parry, and Punch; 22) Seal tightly; 23) Cross hands; and 24) Closing. Highlights indicate the most effective movements; these 5 are also included in the TC-8 form in the accompanying article by Mao et al.
The impact of spinal mobility and sagittal spinal shape on the development of balance impairment supports the hypothesis that enhancing spine flexibility results in an improvement in postural balance ability. Therefore, the aim of this study was to investigate whether the range of motion of thoracolumbar rotation during the movements of the Tai Chi Peking style routine is sufficient to improve thoracolumbar flexibility. Three-dimensional kinematic and kinetic data were collected from 8 athletes of the German Wushu Federation, while performing all movements of the entire Peking style routine (1) in a competition version corresponding to national/international championships and (2) in a health sport version performed with shorter and higher stances (i.e. a smaller distance between the feet and thus less knee flexion). For each movement the total mean and standard deviation values for the total range of motion of thoracolumbar rotation was calculated. Statistical analysis was performed using the Wilcoxon signed-rank test for paired differences. Eight movements showed major differences (10.12–19.73◦) between the two versions. For the remaining movements, only minor differences (0.7–9.56◦) were observed. All movements performed on both sides showed no significant lateral differences. Most of the Tai Chi movements, regardless of the performed version, cover a range of motion of thoracolumbar rotation that has the potential to lead to an improvement of thoracolumbal spine flexibility with appropriate training. The most effective single movements (25.97–72.22◦) are Brush Knee and Step Forward, Step Back and Repulse Monkey, Grasp the Sparrow‘s Tail, Wave Hand in the Clouds, and Fair Lady Weaves with Shuttle.
Source: Wehner C, Wehner C, Schwameder H, Schobersberger W. Thoracolumbar rotation during Tai Chi movements—a biomechanical analysis of the entire Peking Style routine. Front. Sports Act. Living. 2022;4:834355. doi: 10.3389/fspor.2022.834355. Use is per CC Attribution 4.0 International License.
