William W.N. Tsang

Effects of exercise on joint sense and balance in elderly men: Tai Chi versus golf

PURPOSE Our previous studies showed that experienced Tai Chi practitioners had better joint proprioception and balance control during weight shifting. The objective of the present study was to examine whether experienced golfers had attained similar improvement when compared with the Tai Chi practitioners, as well as healthy elderly subjects and young university students. METHODS We compared 12 experienced elderly Tai Chi practitioners, with 11 experienced elderly golfers, 12 healthy elderly subjects, and 12 young university students, who were all males, using: 1) passive knee joint repositioning test to assess their joint proprioceptive acuity and 2) limits of stability test to assess their ability to voluntarily weight shift within their base of support. RESULTS Both Tai Chi practitioners and golfers had better knee joint proprioceptive acuity than did the elderly control subjects (P < 0.05). Of special interest is that their performance was similar to that of the young subjects. In the limits of stability test, Tai Chi practitioners and golfers had faster reaction time, leaned further without losing stability, and showed better control of leaning trajectory than did elderly control subjects (all P < 0.05). The latter two outcome measures were also comparable to those of the young subjects. CONCLUSION These results demonstrate that both experienced Tai Chi practitioners and golfers had improved knee joint proprioception and limits of stability, when compared with those of elderly control subjects similar in age, gender (male), and physical activity level. Such improved outcome measures were comparable to those of young male subjects. These findings suggest that experienced Tai Chi practitioners and golfers had improved joint proprioceptive acuity and dynamic standing balance control, despite the known aging effects in these specific sensorimotor functions.

Balance control in adolescents with idiopathic scoliosis and disturbed somatosensory function.

Study Design. A cross-sectional study of the balance control in adolescents with idiopathic scoliosis. Objective. To investigate the relationship among somatosensory function, balance control, and adolescent idiopathic scoliosis (AIS). Summary of Background Data. Balance control requires the contribution of somatosensory, visual, and vestibular inputs. Previous studies have shown that abnormal somatosensory evoked potentials (SSEPs) were associated with AIS. Methods. A total of 105 girls with AIS and 57 normal girls aged 11–14 years entered the study, and were evaluated with bilateral tibial nerve evoked cerebral SSEPs and standing balance control under reduced or conflicting sensory conditions (i.e., the sensory organization test). One-way analysis of variance was conducted to evaluate the effects of scoliosis and somatosensory function tested by SSEPs on the performance of sensory organization test. Results. There were 15 patients with AIS who had abnormal SSEPs. Postural sway was measured on all subjects under normal, reduced, or conflicting somatosensory, visual, and vestibular conditions. One-way analysis of variance indicated no significant effect of spinal deformity or SSEPs on the balance control when there was an increased reliance on the somatosensory, visual, and vestibular systems during stance (P > 0.05). However, in the patients with abnormal SSEPs, a significant effect was found when subjects had to rely on somatosensory input for their balance control (P = 0.023). The effect of scoliosis by itself was not found to be significant (P = 1.0). Conclusions. The finding of significantly larger difference in bilateral SSEP latencies in patients with AIS indicated the association of abnormal SSEPs with AIS. The finding of a significant effect of SSEPs on the balance control further indicated the presence of abnormal somatosensory function in a subgroup of patients with AIS.

Taekwondo training improves sensory organization and balance control in children with developmental coordination disorder: A randomized controlled trial

Children with developmental coordination disorder (DCD) have poorer postural control and are more susceptible to falls and injuries than their healthy counterparts. Sports training may improve sensory organization and balance ability in this population. This study aimed to evaluate the effects of three months of Taekwondo (TKD) training on the sensory organization and standing balance of children with DCD. It is a randomized controlled trial. Forty-four children with DCD (mean age: 7.6±1.3 years) and 18 typically developing children (mean age: 7.2±1.0 years) participated in the study. Twenty-one children with DCD were randomly selected to undergo daily TKD training for three months (1 h per day). Twenty-three children with DCD and 18 typically developing children received no training as controls. Sensory organization and standing balance were evaluated using a sensory organization test (SOT) and unilateral stance test (UST), respectively. Repeated measures MANCOVA showed a significant group by time interaction effect. Post hoc analysis demonstrated that improvements in the vestibular ratio (p=0.003) and UST sway velocity (p=0.007) were significantly greater in the DCD-TKD group than in the DCD-control group. There was no significant difference in the average vestibular ratio or UST sway velocity between the DCD-TKD and normal-control group after three months of TKD training (p>0.05). No change was found in the somatosensory ratio after TKD training (p>0.05). Significant improvements in visual ratios, vestibular ratios, SOT composite scores and UST sway velocities were also observed in the DCD-TKD group after training (p≤0.01). Three months of daily TKD training can improve sensory organization and standing balance for children with DCD. Clinicians can suggest TKD as a therapeutic leisure activity for this population.

The effects of Tai Chi on the balance control of elderly persons with visual impairment: a randomised clinical trial

BACKGROUND balance control is a major problem for older individuals with poor vision. There are limitations, however, for visually impaired elderly persons wishing to participate in exercise programmes. The benefits of Tai Chi for balance control, muscle strength and preventing falls have been demonstrated with sighted elderly subjects. This study was designed to extend those findings to elderly persons with visual impairment. OBJECTIVE to investigate the effects of Tai Chi on the balance control of elderly persons with visual impairment. DESIGN randomised clinical trial. SETTING residential care homes. SUBJECTS forty visually impaired persons aged 70 or over. METHODS the participants were randomly divided into Tai Chi and control groups and assessed pre- and post-intervention using three tests: (i) passive knee joint repositioning to test knee proprioception; (ii) concentric isokinetic strength of the knee extensors and flexors and (iii) a sensory organisation test to quantify an individuals ability to maintain balance in a variety of complex sensory conditions. RESULTS after intervention, the Tai Chi participants showed significant improvements in knee proprioception and in their visual and vestibular ratios compared with the control group. CONCLUSION practicing Tai Chi can improve the balance control of visually impaired elderly persons.

Altered postural control strategies and sensory organization in children with developmental coordination disorder.

The postural control of children with and without developmental coordination disorder (DCD) was compared under conditions of reduced or conflicting sensory input. Twenty-two children with DCD (16 males, 6 females; mean age 7 years 6 months, SD 1 year 5 months) and 19 children with normal motor development were tested (13 males, 6 females; mean age 6 years 11 months, SD 1 year 1 month). Standing balance, sensory organization and motor control strategy were evaluated using the sensory organization test (SOT). The results revealed that children with DCD had lower composite equilibrium scores (p<.001), visual ratios (p=.005) and vestibular ratios (p=.002) than normal children in the control group. No significant between-group difference in their average somatosensory ratio was observed. Additionally, children with DCD had lower motor strategy scores (swayed more on their hips) than the normal children when forced to depend on vestibular cues alone to balance (p<.05). We conclude that children with DCD had deficits in standing balance control in conditions that included reduced or conflicting sensory signals. The visual and vestibular systems tended to be more involved in contributing to the balance deficits than the somatosensory system. Moreover, children with DCD tended to use hip strategy excessively when forced to rely primarily on vestibular signals to maintain postural stability.

Psycho-physical and neurophysiological effects of qigong on depressed elders with chronic illness

This randomized controlled trial examined the psychological, physical, and neurophysiological effects of a qigong exercise program on depressed elders with chronic medical illness. The experimental group (n = 21, 80 ± 7 years) was given a 12-week qigong exercise program, while the comparison group (n = 17, 81 ± 8 years) participated in a newspaper reading program with the same duration and frequency. Measurement of depression symptoms, psychosocial functioning, muscle strengths, salivary cortisol, and serum serotonin was conducted. At 12 weeks, the qigong group had significant reduction in depressive symptoms (F = 11.68; p < 0.025). Improvement in self-efficacy (F = 4.30; p < 0.050), self-concept of physical well-being (F = 6.82; p < 0.025), and right-hand grip strength (F = 5.25; p = 0.034) was also found when compared with the comparison group. A change in salivary cortisol level was found marginally insignificant between groups (F = 3.16; p = 0.087). However, a decreasing trend of cortisol level was observed. The results provided preliminary evidence for the hypotheses that the antidepressive effect of qigong exercise could be explained by improvement in psychosocial functioning and possibly down-regulation of hyperactivity of the hypothalamic–pituitary–adrenal axis.

Walkway Length, But Not Turning Direction, Determines the Six-Minute Walk Test Distance in Individuals With Stroke

OBJECTIVES To examine (1) the effect of different walkway distances, and (2) turning directions on the six-minute walk test (6MWT) in subjects with stroke. DESIGN A cross-sectional study. SETTING University-based rehabilitation center. PARTICIPANTS Subjects (N=26) with chronic stroke. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Total distance covered and number of turns in the 6MWT with different walkway lengths (10-, 20-, and 30-m walkway distances) and turning directions (turning to affected side and unaffected side); rate of perceived exertion (RPE) using Borg Scale, and heart rate (HR) using handheld pulse oximeter recorded before and immediately after the test. RESULTS The distance covered and the number of turns in the 6MWT were significantly different between different walkway lengths (P<.05), with the longest distance covered and lowest number of turns in the 30-m walkway distance. For all walkway lengths, turning to the affected or unaffected side did not result in significant differences in the distance covered and the number of turns in the 6MWT. Significant increases were found between the pretest and posttest for the HR and RPE (P<.05) in all testing conditions. There was no significant effect of walkway distance and turning direction on the change in HR and RPE between the 6 conditions of the 6MWT. CONCLUSIONS Different walkway distances have a significant effect on the distance covered in the 6MWT, whereas turning direction did not significantly affect the distance covered in the 6MWT.

Differential Effect of Taekwondo Training on Knee Muscle Strength and Reactive and Static Balance Control in Children with Developmental Coordination Disorder: A Randomized Controlled Trial.

This randomized controlled trial aimed to investigate the effect of short-term intensive TKD training on the isokinetic knee muscle strength and reactive and static balance control of children with developmental coordination disorder (DCD). Among the 44 children with DCD (mean age: 7.6 ± 1.3 years) recruited, 21 were randomly assigned to undergo daily TKD training for 1h over three consecutive months, with the remaining 23 children being assigned to the DCD control group. Eighteen typically developing children (mean age: 7.2 ± 1.0 years) received no training as normal controls. Knee extensor and flexor muscle strength and reactive and static balance control were assessed using an isokinetic machine (with low, moderate and high movement velocities), a motor control test (MCT) and a unilateral stance test (UST), respectively. A repeated measures MANCOVA revealed a significant group through time interaction effect in isokinetic outcomes at 180°/s and in the UST outcome. Post hoc analysis demonstrated that DCD-TKD childrens isokinetic knee muscle strength, specifically at 180°/s, was as high as that of the normal control children (p>0.0083) after TKD training. Moreover, UST body sway velocity was slower in the DCD-TKD group than in the DCD control group (p<0.001), and was comparable to that of the normal control group (p>0.05) after TKD training. However, no such improvement in balance was observed in the MCT (p>0.025). The results show that children with DCD who undergo a 3-month program of intensive TKD training experience improvements in isokinetic knee muscle strength at 180°/s and static single-leg standing balance control, but do not benefit from improved reactive balance control.

Effects of aging and Tai Chi on finger-pointing toward stationary and moving visual targets.

UNLABELLED Kwok JC, Hui-Chan CW, Tsang WW. Effects of aging and Tai Chi on finger-pointing toward stationary and moving visual targets. OBJECTIVE To examine the aging effect on speed and accuracy in finger pointing toward stationary and moving visual targets between young and older healthy subjects and whether or not Tai Chi practitioners perform better than healthy older controls in these tasks. DESIGN Cross-sectional study. SETTING University-based rehabilitation center. PARTICIPANTS University students (n=30) (aged 24.2+/-3.1y), were compared with healthy older control subjects (n=30) (aged 72.3+/-7.2y) and experienced (n=31) (mean years of practice, 7.1+/-6.5y) Tai Chi practitioners (aged 70.3+/-5.9y). INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Subjects pointed with the index finger of their dominant hand from a fixed starting position on a desk to a visual signal (1.2cm diameter dot) appearing on a display unit, as quickly and as accurately as possible. Outcome measures included (1) reaction time-the time from the appearance of the dot to the onset of the anterior deltoid electromyographic response; (2) movement time-the time from onset of the electromyographic response to touching of the dot; and (3) accuracy-the absolute deviation of the subjects finger-pointing location from center of the dot. RESULTS Young subjects achieved significantly faster reaction and movement times with significantly better accuracy than older control subjects in all finger-pointing tasks. Tai Chi practitioners attained significantly better accuracy than older controls in pointing to stationary visual signals appearing contralaterally and centrally to their pointing hand. They also demonstrated significantly better accuracy when the target was moving. Accuracy in Tai Chi practitioners was similar to young controls. CONCLUSIONS Eye-hand coordination in finger-pointing declines with age in time and accuracy domains. However, Tai Chi practitioners attained significantly better accuracy than control subjects similar in age, sex, and physical activity level.

Effectiveness of Exergaming Training in Reducing Risk and Incidence of Falls in Frail Older Adults With a History of Falls

OBJECTIVE To use Nintendos Wii Fit balance board to determine the effectiveness of exergaming training in reducing risk and incidence of falls in older adults with a history of falls. DESIGN Randomized controlled trial. SETTING Nursing home for older adults. PARTICIPANTS Adults aged 65 years and older (N=60). INTERVENTIONS Participants who lived in a nursing home had 6 weeks of balance training with either Wii Fit equipment or conventional exercise. MAIN OUTCOME MEASURES Physiological Profile Assessment scores and incidence of falls were observed with subsequent intention-to-treat statistical analyses. RESULTS Physiological Profile Assessment scores and incidence of falls improved significantly in both groups after the intervention (all P<.01), but participants in the Wii Fit training group showed a significantly greater improvement in both outcome measures (P=.004 and P<.001, respectively). CONCLUSIONS In institutionalized older adults with a history of falls, Wii Fit balance training was more effective than conventional balance training in reducing the risk and incidence of falls.