Martin Grønbech Jørgensen

Efficacy of Nintendo Wii Training on Mechanical Leg Muscle Function and Postural Balance in Community-Dwelling Older Adults: A Randomized Controlled Trial

BACKGROUND Older adults show increased risk of falling and major risk factors include impaired lower extremity muscle strength and postural balance. However, the potential positive effect of biofeedback-based Nintendo Wii training on muscle strength and postural balance in older adults is unknown. METHODS This randomized controlled trial examined postural balance and muscle strength in community-dwelling older adults (75±6 years) pre- and post-10 weeks of biofeedback-based Nintendo Wii training (WII, n = 28) or daily use of ethylene vinyl acetate copolymer insoles (controls [CON], n = 30). Primary end points were maximal muscle strength (maximal voluntary contraction) and center of pressure velocity moment during bilateral static stance. RESULTS Intention-to-treat analysis with adjustment for age, sex, and baseline level showed that the WII group had higher maximal voluntary contraction strength (18%) than the control group at follow up (between-group difference = 269 N, 95% CI = 122; 416, and p = .001). In contrast, the center of pressure velocity moment did not differ (1%) between WII and CON at follow-up (between-group difference = 0.23 mm(2)/s, 95% CI = -4.1; 4.6, and p = .92). For secondary end points, pre-to-post changes favoring the WII group were evident in the rate of force development (p = .03), Timed Up and Go test (p = .01), short Falls Efficacy Scale-International (p = .03), and 30-second repeated Chair Stand Test (p = .01). Finally, participants rated the Wii training highly motivating at 5 and 10 weeks into the intervention. CONCLUSIONS Biofeedback-based Wii training led to marked improvements in maximal leg muscle strength (maximal voluntary contraction; rate of force development) and overall functional performance in community-dwelling older adults. Unexpectedly, static bilateral postural balance remained unaltered with Wii training. The high level of participant motivation suggests that biofeedback-based Wii exercise may ensure a high degree of compliance to home- and/or community-based training in community-dwelling older adults.

Time-of-day influences postural balance in older adults

BACKGROUND Postural balance assessments are performed in both clinical and basic research settings on a daily basis. During a 24-h time span our physiology and physical performance undergo radical changes as we are influenced by the circadian rhythm. The time-of-day interaction on postural balance is unknown in older adults. The aim of this study was to investigate the time-of-day effect on postural balance in older adults. METHODS Center of pressure (CoP) excursion was measured (100 Hz) by force plate analysis in 34 older adults during 30 s of narrow quiet bilateral stance. Measurements were performed around 9a.m., 12.30 p.m. and 4 p.m. on the same day. Postural balance was quantified by velocity-moment, confidence ellipse area, total sway area and total sway length. RESULTS An overall significant time-of-day (between 9 a.m. and 4 p.m.) effect was observed for velocity-moment (mm(2)/s) 57 ± 27-65 ± 29 (p = 0.001), confidence ellipse area (mm(2)) 36 ± 16-44 ± 19 (p < 0.001), total sway area (mm(2)) 548 ± 263-627 ± 285 (p = 0.001) and total sway length (mm) 373 ± 120-379 ± 113 (p = 0.037). The variation of postural balance was mostly pronounced from midday (12.30 p.m.) toward the afternoon (4 p.m.) in all sway parameters. Specifically between 12.30 p.m. and 4 p.m. confidence ellipse area increased by 18.5%, total sway area by 17.1%, velocity-moment by 15.8% and total sway length by 4.6%. No differences were observed between 9 a.m. and 12.30 p.m. in any of the sway parameters. CONCLUSIONS This study demonstrates that time-of-day influences postural balance in older adults. These findings have important scientific and clinical relevance, as they imply that time-of-day should be a controlled factor when assessing postural balance in older adults.

Impaired postural balance in the morning in patients with knee osteoarthritis

Postural balance (PB) is frequently used as an outcome measure in clinical and research settings when assessing patients with knee osteoarthritis (OA). Pain and stiffness is known to affect PB, and is elevated in the morning and evening in OA patients. The aim of this study was to explore if time-of-day affects PB control in knee OA patients. Centre Of Pressure (COP) excursion was measured (100Hz) by force plate technique at selected time-points (9.00 a.m., 12.30 p.m. and 4.00 p.m.) during a single day in 32 knee OA patients aged 66.0 (10.3) years. A rigorous protocol was followed to ensure comparable testing conditions across time-points. PB control was quantified by the COP variables: velocity moment (mm(2)/s), total sway area (mm(2)), total sway length (mm) and confidence ellipse area (mm(2)). A two-way mixed-effects model showed that PB significantly improved between 9.00 a.m. and 12.30 p.m. in three out of four COP variables. The observed improvement was 11.9% (p=0.011) for velocity moment, 12.2% (p=0.011) for total sway area and 9.4% (p<0.001) for total sway length. PB appears to be impaired in the morning relative to midday in knee OA patients. Thus, it is recommended that time of assessment is standardized between sessions when assessing PB in clinical and research settings in knee OA patients.

Intrarater reproducibility and validity of Nintendo Wii balance testing in community-dwelling older adults.

The aims of the current study were to examine the intrarater intersession reproducibility of the Nintendo Wii agility and stillness tests and explore the concurrent validity in relation to gold-standard force-plate analysis. Within-day intersession reproducibility was examined in 30 older adults (age 71.8 ± 5.1 yr). No systematic test-retest differences were found for the Wii stillness test; however, the Wii agility test scores differed systematically between test sessions (p < .05). The Wii stillness test yielded a test-retest ICC of .86 (95% CI 0.74-0.93), CV of 6.4%, LOA of 11.0, and LOA% of 17.9%. Likewise for the Wii agility test ICC was .73 (95% CI 0.50-0.86), CV 5.3%, LOA 1.8, and LOA% of 14.6%. Wii stillness scores correlated to force plate measures (r = .65-.82, p < .01), reflecting moderate to excellent validity. In conclusion, it appears that the Wii stillness test represents a low-cost, objective, reproducible, and valid test of undisturbed postural balance in community-dwelling older adults.

Field assessment of balance in 10 to 14 year old children, reproducibility and validity of the Nintendo Wii board

BackgroundBecause body proportions in childhood are different to those in adulthood, children have a relatively higher centre of mass location. This biomechanical difference and the fact that children’s movements have not yet fully matured result in different sway performances in children and adults. When assessing static balance, it is essential to use objective, sensitive tools, and these types of measurement have previously been performed in laboratory settings. However, the emergence of technologies like the Nintendo Wii Board (NWB) might allow balance assessment in field settings. As the NWB has only been validated and tested for reproducibility in adults, the purpose of this study was to examine reproducibility and validity of the NWB in a field setting, in a population of children.MethodsFifty-four 10–14 year-olds from the CHAMPS-Study DK performed four different balance tests: bilateral stance with eyes open (1), unilateral stance on dominant (2) and non-dominant leg (3) with eyes open, and bilateral stance with eyes closed (4). Three rounds of the four tests were completed with the NWB and with a force platform (AMTI). To assess reproducibility, an intra-day test-retest design was applied with a two-hour break between sessions.ResultsBland-Altman plots supplemented by Minimum Detectable Change (MDC) and concordance correlation coefficient (CCC) demonstrated satisfactory reproducibility for the NWB and the AMTI (MDC: 26.3-28.2%, CCC: 0.76-0.86) using Centre Of Pressure path Length as measurement parameter. Bland-Altman plots demonstrated satisfactory concurrent validity between the NWB and the AMTI, supplemented by satisfactory CCC in all tests (CCC: 0.74-0.87). The ranges of the limits of agreement in the validity study were comparable to the limits of agreement of the reproducibility study.ConclusionBoth NWB and AMTI have satisfactory reproducibility for testing static balance in a population of children. Concurrent validity of NWB compared with AMTI was satisfactory. Furthermore, the results from the concurrent validity study were comparable to the reproducibility results of the NWB and the AMTI. Thus, NWB has the potential to replace the AMTI in field settings in studies including children. Future studies are needed to examine intra-subject variability and to test the predictive validity of NWB.

Novel Use of the Nintendo Wii Board for Measuring Isometric Lower Limb Strength: A Reproducible and Valid Method in Older Adults.

Background Portable, low-cost, objective and reproducible assessment of muscle strength in the lower limbs is important as it allows clinicians to precisly track progression of patients undergoing rehabilitation. The Nintendo Wii Balance Board (WBB) is portable, inexpensive, durable, available worldwide, and may serve the above function. Objective The purpose of the study was to evaluate (1) reproducibility and (2) concurrent validity of the WBB for measuring isometric muscle strength in the lower limb. Methods A custom hardware and software was developed to utilize the WBB for assessment of isometric muscle strength. Thirty older adults (69.0±4.2 years of age) were studied on two separate occasions on both the WBB and a stationary isometric dynamometer (SID). On each occasion, three recordings were obtained from each device. For the first recording, means and maximum values were used for further analysis. The test-retest reproducibility was examined using intraclass correlation coefficients (ICC), Standard Error of Measurement (SEM), and limits of agreement (LOA). Bland-Altman plots (BAP) and ICC’s were used to explore concurrent validity. Results No systematic difference between test-retest was detected for the WBB. ICC within-device were between 0.90 and 0.96 and between-devices were from 0.80 to 0.84. SEM ranged for the WBB from 9.7 to 13.9%, and for the SID from 11.9 to 13.1%. LOA ranged for the WBB from 20.3 to 28.7% and for the SID from 24.2 to 26.6%. The BAP showed no relationship between the difference and the mean. Conclusions A high relative and an acceptable absolute reproducibility combined with a good validity was found for the novel method using the WBB for measuring isometric lower limb strength in older adults. Further research using the WBB for assessing lower limb strength should be conducted in different study-populations.

The cognitive complexity of concurrent cognitive-motor tasks reveals age-related deficits in motor performance

Aging reduces cognitive functions, and such impairments have implications in mental and motor performance. Cognitive function has been recently linked to the risk of falls in older adults. Physical activities have been used to attenuate the declines in cognitive functions and reduce fall incidence, but little is known whether a physically active lifestyle can maintain physical performance under cognitively demanding conditions. The aim of this study was to verify whether physically active older adults present similar performance deficits during upper limb response time and precision stepping walking tasks when compared to younger adults. Both upper limb and walking tasks involved simple and complex cognitive demands through decision-making. For both tasks, decision-making was assessed by including a distracting factor to the execution. The results showed that older adults were substantially slower than younger individuals in the response time tasks involving decision-making. Similarly, older adults walked slower and extended the double support periods when precision stepping involved decision-making. These results suggest that physically active older adults present greater influence of cognitive demanding contexts to perform a motor task when compared to younger adults. These results underpin the need to develop interventions combining cognitive and motor contexts.

Activities Of Daily Living At Admission To Acute Geriatric Departments Predicts Hip Fracture: A Nationwide Cohort Study

Introduction: Falls are the leading cause of fatal and non-fatal unintentional injuries in older people. Despite overwhelming evidence for strength/balance training, adherence to both group and home-exercise programmes is often poor1. A novel approach is the use of home-based, strength and balance video-games (EXERGAMES) but data from randomized controlled trials are limited2. The aim of this study was to test whether a 12 week EXERGAMES home-based intervention, co-developed with older adults and therapists, can improve the risk of falling [by Berg Balance Scale (BBS)] in older adults living in sheltered housing. Methods: We conducted a two-site (Manchester/Glasgow) cluster RCT. Twelve sheltered housing facilities were randomised (1:1) to either a 12wk standard care plus 3 times/ week EXERGAMES physiotherapist one-to-one intervention (n=56) or standard care (control group n=50). Standard care involved the provision of a home exercise booklet (standard approach for those unable/unwilling to attend group exercise programmes in the community). Results: A total of 106 older adults (83F, 23M) with a mean age of 77.8y (SD 10.2; range 55-101y), were recruited for the study. A total of 91 (86%) participants completed all study visits. Over 12 weeks the EXERGAMES intervention had a significant positive impact on BBS [p=0.003; mean (SD), 44.6 (10.7) (EXERGAMES) vs. 37.6 (14.9) (Control)]. The mean change of BBS from baseline was 2.9 (8.5) for the EXERGAMES and -2.8 (6.5) for the control group. The estimated increase in BBS score due to EXERGAMES was 6.2 (95% CI 2.4 to 9.9) which is greater than the minimal detectable change for the scale of 4.93. Conclusions: Balance, and thus risk of falling, can be improved through a 12wk physiotherapy led EXERGAMES programme. This type of home based intervention could be considered as an effective alternative to traditional falls prevention exercise regimes to support outcomes for patients.

Handgrip force steadiness in young and older adults: a reproducibility study

BackgroundForce steadiness is a quantitative measure of the ability to control muscle tonus. It is an independent predictor of functional performance and has shown to correlate well with different degrees of motor impairment following stroke. Despite being clinically relevant, few studies have assessed the validity of measuring force steadiness. The aim of this study was to explore the reproducibility of handgrip force steadiness, and to assess age difference in steadiness.MethodIntrarater reproducibility (the degree to which a rating gives consistent result on separate occasions) was investigated in a test-retest design with seven days between sessions. Ten young and thirty older adults were recruited and handgrip steadiness was tested at 5%, 10% and 25% of maximum voluntary contraction (MVC) using Nintendo Wii Balance Board (WBB). Coefficients of variation were calculated from the mean force produced (CVM) and the target force (CVT). Area between the force curve and the target force line (Area) was also calculated. For the older adults we explored reliability using intraclass correlation coefficient (ICC) and agreement using standard error of measurement (SEM), limits of agreement (LOA) and smallest real difference (SRD).ResultsA systematic improvement in handgrip steadiness was found between sessions for all measures (CVM, CVT, Area). CVM and CVT at 5% of MVC showed good to high reliability, while Area had poor reliability for all percentages of MVC. Averaged ICC for CVM, CVT and Area was 0.815, 0.806 and 0.464, respectively. Averaged ICC on 5%, 10%, and 25% of MVC was 0.751, 0.667 and 0.668, respectively. Measures of agreement showed similar trends with better results for CVM and CVT than for Area. Young adults had better handgrip steadiness than older adults across all measures.ConclusionThe CVM and CVT measures demonstrated good reproducibility at lower percentages of MVC using the WBB, and could become relevant measures in the clinical setting. The Area measure had poor reproducibility. Young adults have better handgrip steadiness than old adults.

Reference data on reaction time and aging using the Nintendo Wii Balance Board: A cross-sectional study of 354 subjects from 20 to 99 years of age

Background Falls among older adults is one of the major public health challenges facing the rapidly changing demography. The valid assessment of reaction time (RT) and other well-documented risk factors for falls are mainly restricted to specialized clinics due to the equipment needed. The Nintendo Wii Balance Board has the potential to be a multi-modal test and intervention instrument for these risk factors, however, reference data are lacking. Objective To provide RT reference data and to characterize the age-related changes in RT measured by the Nintendo Wii Balance Board. Method Healthy participants were recruited at various locations and their RT in hands and feet were tested by six assessors using the Nintendo Wii Balance Board. Reference data were analysed and presented in age-groups, while the age-related change in RT was tested and characterized with linear regression models. Results 354 participants between 20 and 99 years of age were tested. For both hands and feet, mean RT and its variation increased with age. There was a statistically significant non-linear increase in RT with age. The averaged difference between male and female was significant, with males being faster than females for both hands and feet. The averaged difference between dominant and non-dominant side was non-significant. Conclusion This study reported reference data with percentiles for a new promising method for reliably testing RT. The RT data were consistent with previously known effects of age and gender on RT.