Cost-Effectiveness and Cost-Utility of a Home-Based Exercise Program in Geriatric Patients with Cognitive Impairment.

INTRODUCTION: There is a substantial lack of home-based exercise programs in the highly vulnerable group of geriatric patients with cognitive impairment (CI) after discharge from ward rehabilitation. Beyond clinical effectiveness, the cost-effectiveness of intervention programs to enhance physical performance is not well investigated in this target group. OBJECTIVE: The aim of the study was to determine the cost-effectiveness of a 12-week home-based exercise intervention following discharge from ward rehabilitation compared to unspecified flexibility training for geriatric patients with CI from a societal perspective. METHODS: This cost-effectiveness study was conducted alongside a randomized placebo-controlled trial. A total of 118 geriatric patients with CI (Mini-Mental State Examination score: 17-26) were randomized either to the intervention group (IG, n = 63) or control group (CG, n = 55). Participants in the IG received a home-based individually tailored exercise program to increase physical performance, while participants in the CG received unspecific flexibility training (placebo control). Healthcare service use, physical performance (Short Physical Performance Battery, SPPB), and quality of life (EQ-5D-3L) were measured over 24 weeks. The net monetary benefit (NMB) approach was applied to calculate incremental cost-effectiveness of the exercise intervention compared to the CG with respect to improvement of (a) physical performance on the SPPB and (b) quality-adjusted life years (QALYs). RESULTS: Physical performance was significantly improved in the IG compared to the CG (mean difference at 24 weeks: 1.3 points; 95% confidence interval [95% CI] = 0.5-2.2; p = 0.003), while health-related quality of life did not significantly differ between the groups at 24 weeks (mean difference: 0.08; 95% CI = -0.05 to 0.21; p = 0.218). Mean costs to implement the home-based exercise intervention were EUR 284 per patient. The probability of a positive incremental NMB of the intervention reached a maximum of 92% at a willingness to pay (WTP) of EUR 500 per point on the SPPB. The probability of cost-utility referring to QALYs was 85% at a WTP of EUR 5,000 per QALY. CONCLUSION: The home-based exercise intervention demonstrated high probability of cost-effectiveness in terms of improved physical performance in older adults with CI following discharge from ward rehabilitation, but not in terms of quality of life.

Increasing Life-Space Mobility in Community-Dwelling Older Persons With Cognitive Impairment Following Rehabilitation: A Randomized Controlled Trial.

BACKGROUND: Community-dwelling older persons with cognitive impairment (CI) following discharge from geriatric rehabilitation are at high risk of losing life-space mobility (LSM). Interventions to improve their LSM are, however, still lacking. The aim of this study was to evaluate the effects of a CI-specific, home-based physical training and activity promotion program on LSM. METHODS: Older persons with mild-to-moderate CI (Mini-Mental State Examination: 17-26 points) discharged home from rehabilitation were included in this double-blinded, randomized, placebo-controlled trial with a 12-week intervention period and 12-week follow-up period. The intervention group received a CI-specific, home-based strength, balance, and walking training supported by tailored motivational strategies. The control group received a placebo activity. LSM was evaluated by the Life-Space Assessment in Persons with Cognitive Impairment, including a composite score for LSM and 3 subscores for maximal, equipment-assisted, and independent life space. Mixed-model repeated-measures analyses were used. RESULTS: One hundred eighteen participants (82.3 ± 6.0 years) with CI (Mini-Mental State Examination: 23.3 ± 2.4) were randomized. After the intervention, the home-based training program resulted in a significant benefit in the Life-Space Assessment in Persons with Cognitive Impairment composite scores (b = 8.15; 95% confidence interval: 2.89-13.41; p = .003) and independent life-space subscores (b = 0.39; 95% confidence interval: 0.00-0.78; p = .048) in the intervention group (n = 63) compared to control group (n = 55). Other subscores and follow-up results were not significantly different. CONCLUSIONS: The home-based training program improved LSM and independent life space significantly in this vulnerable population. Effects were not sustained over the follow-up. The program may represent a model for improved transition from rehabilitation to the community to prevent high risk of LSM restriction.

Promoting physical activity in geriatric patients with cognitive impairment after discharge from ward-rehabilitation: a feasibility study.

The aim of the present study was to examine adherence and acceptance of a home-based program to promote physical activity (PA) in older persons with cognitive impairment (CI) following inpatient rehabilitation. Sixty-three older persons (≥ 65 years) with mild to moderate CI (Mini-Mental State Examination score 17-26), allocated to the intervention group of a randomized, controlled intervention trial underwent a 12-week home-based PA intervention including (1) physical training and outdoor walking to improve functional fitness and (2) motivational strategies (goal-setting, pedometer-based self-monitoring, social support delivered by home visits, phone calls) to promote PA. Training logs were used to assess adherence to physical training, outdoor walking and to motivational strategies (goal-setting, pedometer-based self-monitoring). Acceptance (subjective feasibility and effectiveness) of the program components was assessed by a standardized questionnaire. Mean adherence rates over the intervention period were 63.6% for physical training, 57.9% for outdoor walking, and between 40.1% (achievement of walking goals), and 60.1% (pedometer-based self-monitoring) for motivational strategies. Adherence rates significantly declined from baseline to the end of intervention (T1: 43.4-76.8%, T2: 36.1-51.5%, p values<.019). Most participants rated physical training, outdoor walking, goal-setting, and pedometer self-monitoring as feasible (68.2-83.0%) and effective (63.5-78.3%). Highest ratings of self-perceived effectiveness were found for home visits (90.6%) and phone calls (79.2%). The moderate to high adherence to self-performed physical training and motivational strategies proved the feasibility of the home-based PA program in older persons with CI following inpatient rehabilitation.

Effect of practice on learning to maintain balance under dynamic conditions in children: are there sex differences?

BACKGROUND: In youth, sex-related differences in balance performances have been reported with girls usually outperforming same-aged boys. However, it is not known whether sex also has an influence on learning of a new balance task in primary school-aged children. Therefore, the present study investigated sex-related differences in children learning to maintain balance under dynamic conditions. METHODS: Thirty-two children (16 girls, 16 boys) aged 8.5 ± 0.5 years practiced balancing on a stabilometer (i.e., to keep it as horizontal as possible) for seven trials (90 s each) on two consecutive days. Knowledge of results (KR) (i.e., time in balance) was provided after each trial. On day three learning was assessed using a retention test (i.e., balance task only) and a test of automation (i.e., balance plus concurrent motor interference task). Root-mean-square-error (RMSE) was recorded for all trials and used for further analysis. RESULTS: During practicing (Day 1, Day 2) RMSE values significantly decreased over the days (p = 0.019, d = 0.92) and trials (p = 0.003, d = 0.70) in boys and girls. Further, the main effect of sex showed a tendency toward significance (p = 0.082, d = 0.67). On day 3, the girls showed significantly smaller RMSE values compared to boys in the retention (p = 0.012, d = 1.00) and transfer test (p = 0.045, d = 0.74). CONCLUSIONS: Performance increases during the acquisition phase tended to be larger in girls than in boys. Further, learning (i.e., retention and automation) was significantly larger in girls compared to boys. Therefore, practitioners (e.g., teachers, coaches) should supply boys and grils with balance exercises of various task difficulties and complexities to address their diverse learning progress.

Effects of Balance Training on Balance Performance in Youth: Are There Age Differences?

Purpose: In youth, cross-sectional studies reported age differences in balance performance that were in favor of adolescents. Thus, trainability of balance performance might be different in children compared to adolescents. The purpose of this study was therefore to compare the effects of balance training (BT) on balance performance between children and adolescents.Method: Thirty children (7.5 ± 0.5 years) and 42 adolescents (14.7 ± 0.5 years) participated in this study and were assigned to either a BT-group or a control (CON) group. In both age groups, BT was conducted over five weeks while the CON-groups received their regular physical education lessons. Pre- and posttests included the assessment of mobility, static steady-state, proactive, and reactive balance.Results: Significant Test × Group × Age interactions were found for static steady-state balance (i.e., CoP displacements during single leg stance) and mobility (i.e., 10-m gait velocity). For both measures, post hoc analysis revealed larger improvements (+16-37%, 0.001 ≤ p ≤ 0.033, 0.65 ≤ d ≤ 2.24) for children compared to adolescents. For proxies of proactive and reactive balance, we could not detect significant Test × Group × Age interactions.Conclusions: We conclude that trainability of static steady-state balance and mobility seems to be higher in children than in adolescents indicating larger adaptive reserves in children compared to adolescents. However, there were no age differences in adaptations to BT with respect to proactive and reactive balance.

RELIABILITY AND MINIMAL DETECTABLE CHANGE OF THE UPPER QUARTER Y-BALANCE TEST IN HEALTHY ADOLESCENTS AGED 12 TO 17 YEARS.

PURPOSE/BACKGROUND: There are a few studies investigating the reproducibility of the Upper Quarter Y Balance Test (YBT-UQ) in adults. However, no study has determined test-retest reliability and the minimal detectable change of the YBT-UQ in adolescents from different age cohorts. The aim of the present study was to establish test-retest reliability and minimal detectable change of the YBT-UQ in a sample of healthy adolescents. METHODS: In a school setting, 111 students (59 female, 52 male) aged 12-17 years performed the YBT-UQ twice, separated by one week. Normalized maximal reach distances (% arm length) for all three directions (i.e., medial, inferolateral, superolateral) and the composite score were used as outcome measures. Intraclass correlation coefficient (ICC3,1) and standard error of measurement (SEM) were calculated to assess both relative and absolute test-retest reliability. In addition, the minimal detectable change (MDC95%), an index that is defined as the minimal amount of change in performance that falls outside the measurement error or performance changes due to variability was determined. RESULTS: Irrespective of age cohort, reach arm, and reach direction, the measure of relative reliability ranged from "moderate-to-good" to "excellent" ICC values and the proxy of absolute reliability was rather small (i.e., SEM ≤ 7.6%). The MDC95% needed to identify relevant effects in repeated measurements of the YBT-UQ performance ranged between 4.8% and 21.1%, depending on age, reach arm, and reach direction. CONCLUSIONS: The detected values imply that the YBT-UQ is a reliable field test that can be used to detect changes of upper quarter mobility/stability in healthy adolescents aged 12-17 years. LEVEL OF EVIDENCE: 2b.

Effects of a blocked versus an alternated sequence of balance and plyometric training on physical performance in youth soccer players.

BACKGROUND: The sequence of blocked balance training (BT) followed by blocked plyometric training (PT) showed greater improvements in physical performance than vice versa and is explained by a preconditioning effect of BT-related adaptations on subsequent adaptations induced by PT. However, it remains unclear whether beneficial effects can also be induced using alternating instead of blocked BT and PT exercise sequences. Thus, we examined the effects of a blocked versus an alternated sequence of BT and PT on physical performance in trained individuals. METHODS: Twenty young soccer players (13 years) were randomly assigned to a blocked (n = 10) or an alternated (n = 10) intervention group. Both groups trained balance and plyometric exercises for six weeks (two sessions/week). The exercises were conducted in a blocked (three weeks of BT followed by three weeks of PT) or an alternated sequence (weekly change of BT and PT). Assessment of pre- and post-training performance included measures of balance, muscle power, speed, and agility. RESULTS: Mainly significant main effects of Test (i.e., pre- to post-test improvements) were observed for the Y-balance test (p ≤ 0.014, 1.3 ≤ Cohen's d ≤ 1.81), the squat jump (p = 0.029, d = 1.36), the countermovement jump (p = 0.002, d = 2.21), the drop jump (p = 0.004, d = 1.96), the split times/total time over 15-m sprinting (p ≤ 0.001, 2.02 ≤ d ≤ 3.08), and the figure-T agility run (p < 0.001, d = 3.80). Further, tendencies toward significant Test x Group interactions were found for several items of the Y-balance test and for SJ height in favor of the blocked BTPT group. CONCLUSIONS: Our results indicate that the combined training of balance and plyometric exercises is effective to improve proxies of physical performance in youth soccer players. In addition, there is a limited advantage in some parameters of balance and muscle power for the blocked as compared to the alternated sequence of BT and PT.

Validity, reliability, and feasibility of the uSense activity monitor to register physical activity and gait performance in habitual settings of geriatric patients.

OBJECTIVE: The aim of the study was to investigate the psychometric quality of a newly developed activity monitor (uSense) to document established physical activity parameters as well as innovative qualitative and quantitative gait characteristics in geriatric patients. APPROACH: Construct and concurrent validity, test-retest reliability, and feasibility of established as well as innovative characteristics for qualitative gait analysis were analyzed in multi-morbid, geriatric patients with cognitive impairment (CI) (n = 110), recently discharged from geriatric rehabilitation. MAIN RESULTS: Spearman correlations of established and innovative uSense parameters reflecting active behavior with clinically relevant construct parameters were on average moderate to high for motor performance and life-space and low to moderate for other parameters, while correlations with uSense parameters reflecting inactive behavior were predominantly low. Concurrent validity of established physical activity parameters showed consistently high correlations between the uSense and an established comparator system (PAMSys™), but the absolute agreement between both sensor systems was low. On average excellent test-retest reliability for all uSense parameters and good feasibility could be documented. SIGNIFICANCE: The uSense monitor allows the assessment of established and-for the first time-a semi-qualitative gait assessment of habitual activity behavior in older persons most affected by motor and CI and activity restrictions. On average moderate to good construct validity, high test-retest reliability, and good feasibility indicated a sound psychometric quality of most measures, while the results of concurrent validity as measured by a comparable system indicated high correlation but low absolute agreement based on different algorithms used.

Age and sex differences in human balance performance from 6-18 years of age: A systematic review and meta-analysis.

BACKGROUND: The process of growing leads to inter-individual differences in the timing of growth, maturational, and developmental processes during childhood and adolescence, also affecting balance performance in youth. However, differences in balance performance by age and sex in youth have not been systematically investigated yet. OBJECTIVE: The objective of the present study was to characterize and quantify age- and sex-related differences in balance performance in healthy youth. METHODS: A computerized systematic literature search was performed in the electronic databases PubMed, Web of Science, and SPORTDiscus. To be applicable for analysis, studies had to report at least one measure of static steady-state, dynamic steady-state, proactive or reactive balance in healthy children (6-12 years) and/or adolescents (13-18 years). Coding of the studies was done according to the following criteria: age, sex, and balance outcome. Study quality was assessed using the Appraisal tool for Cross-Sectional Studies. Weighted standardized mean differences were calculated and classified according to their magnitude. RESULTS: Twenty-one studies examined age-related differences in balance performance. A large effect for measures of static steady-state balance (SMDba = 1.20) and small effects for proxies of dynamic steady-state (SMDba = 0.26) and proactive balance (SMDba = 0.28) were found; all in favor of adolescents. Twenty-five studies investigated sex-related differences in balance performance. A small-sized effect was observed for static steady-state balance (SMDbs = 0.33) in favor of girls and for dynamic steady-state (SMDbs -0.02) and proactive balance (SMDbs = -0.15) in favor of boys. Due to a lack of studies, no analysis for measures of reactive balance was performed. CONCLUSIONS: Our systematic review and meta-analysis revealed better balance performances in adolescents compared to children, irrespective of the measure considered. Sex-related differences were inconsistent. These findings may have implications for example in terms of trainability of balance in youth that should be investigated in future studies.

Effects of motor practice on learning a dynamic balance task in healthy young adults: A wavelet-based time-frequency analysis.

BACKGROUND: Previous research showed changes in amplitude- or time-derived measures of electromyographic (EMG) activity with motor learning. However, an analysis of the EMG spectral content (e.g., via wavelet technique) has not been included in these investigations yet. OBJECTIVE: The aim of this study was to use conventional, amplitude-derived EMG parameters along with modern, wavelet-based time-frequency EMG measures to assess the effects of motor practice on learning a dynamic balance task. METHODS: Nineteen young male adults (mean age: 26 ± 6 years) practiced a dynamic balance task for two days. Delayed retention test was performed on the third day. On a behavioral level, the root-mean-square error (RMSE) of the stability platform angle was calculated and used as outcome measure. On a neuromuscular level, EMG data from the tibialis anterior (TA) and the gastrocnemius medialis (GM) muscle were unilaterally recorded and analysed by calculating the integrated EMG (iEMG) and the EMG intensity (via continuous wavelet transforms). RESULTS: Two days of practice resulted in significantly improved balance performance (i.e., lower RMSE) and TA/GM activation (i.e., reduced iEMG and EMG intensity) that was still present during the retention test on day 3. There was also evidence of practice-related changes in the EMG intensity pattern as indicated by an intensity shift from higher to lower frequency components. CONCLUSIONS: We conclude that motor practice leads to improvements in movement effectiveness as indicated by reduced RMSE and in movement efficiency (i.e., decreased iEMG and EMG intensity, intensity shift). In addition to conventional amplitude-derived EMG parameters, modern, wavelet-based time-frequency EMG measures are appropriate to detect practice-related changes in muscle activation.

Limb Differences in Unipedal Balance Performance in Young Male Soccer Players with Different Ages.

In soccer, the dominant leg is frequently used for passing and kicking while standing on the non-dominant leg. Consequently, postural control in the standing leg might be superior compared to the kicking leg and is further enhanced with increasing age (i.e., level of playing experience). Unfortunately, leg differences in postural control are associated with an increased risk of injuries. Thus, we examined differences between limbs in unipedal balance performance in young soccer players at different ages. Performance in the Lower Quarter Y Balance Test (YBT-LQ) of the dominant and non-dominant leg and anthropometry was assessed in 76 young male soccer players (under-13 years [U13]: n = 19, U15: n = 14, U17: n = 21, U19: n = 22). Maximal reach distances (% leg length) and the composite scores were used for further analyses. Statistical analyses yielded no statistically significant main effects of leg or significant Leg × Age interactions, irrespective of the measure investigated. However, limb differences in the anterior reach direction were above the proposed cut-off value of >4 cm, which is indicative of increased injury risk. Further, statistically significant main effects of age were found for all investigated parameters, indicating larger reach distances in older (U19) compared to younger (U13) players (except for U15 players). Although reach differences between legs were non-significant, the value in the anterior reach direction was higher than the cut-off value of >4 cm in all age groups. This is indicative of an increased injury risk, and thus injury prevention programs should be part of the training of young soccer players.

Life-space mobility in older persons with cognitive impairment after discharge from geriatric rehabilitation.

OBJECTIVES: To describe life-space mobility and identify its determinants in older persons with cognitive impairment after discharge from geriatric rehabilitation. METHODS: A cross-sectional study in older community-dwelling persons with mild to moderate cognitive impairment (Mini-Mental State Examination, MMSE: 17-26) following geriatric rehabilitation was conducted. Life-space mobility (LSM) was evaluated by the Life-Space Assessment in Persons with Cognitive Impairment (LSA-CI). Bivariate analyses and multivariate regression analyses were used to investigate associations between LSM and physical, cognitive, psychosocial, environmental, financial and demographic characteristics, and physical activity behavior. RESULTS: LSM in 118 older, multimorbid participants (age: 82.3 ± 6.0 years) with cognitive impairment (MMSE score: 23.3 ± 2.4 points) was substantially limited, depending on availability of personal support and equipment. More than 30% of participants were confined to the neighborhood and half of all patients could not leave the bedroom without equipment or assistance. Motor performance, social activities, physical activity, and gender were identified as independent determinants of LSM and explained 42.4% (adjusted R²) of the LSA-CI variance in the regression model. CONCLUSION: The study documents the highly restricted LSM in older persons with CI following geriatric rehabilitation. The identified modifiable determinants of LSM show potential for future interventions to increase LSM in such a vulnerable population at high risk for restrictions in LSM by targeting motor performance, social activities, and physical activity. A gender-specific approach may help to address more advanced restrictions in women.

Validation of a Modified Life-Space Assessment in Multimorbid Older Persons With Cognitive Impairment.

BACKGROUND AND OBJECTIVES: To investigate the validity, reliability, sensitivity to change, and feasibility of a modified University of Alabama at Birmingham Study of Aging Life-Space Assessment (UAB-LSA) in older persons with cognitive impairment (CI). RESEARCH DESIGN AND METHODS: The UAB-LSA was modified for use in persons with CI Life-Space Assessment for Persons with Cognitive Impairment (LSA-CI). Measurement properties of the LSA-CI were investigated using data of 118 multimorbid older participants with CI [mean age (SD): 82.3 (6.0) years, mean Mini-Mental State Examination score: 23.3 (2.4) points] from a randomized controlled trial (RCT) to improve motor performance and physical activity. Construct validity was asessed by Spearman's rank (rs) and point-biseral correlations (rpb) with age, gender, motor, and cognitive status, psychosocial factors, and sensor-derived (outdoor) physical activity variables. Test-retest reliability was analyzed using intra-class correlation coefficients (ICCs). Sensitivity to change was determined by standardized response means (SRMs) calculated for the RCT intervention group. RESULTS: The LSA-CI demonstrated moderate to high construct validity, with significant correlations of the LSA-CI scores with (outdoor) physical activity (rs = .23-.63), motor status (rs = .27-.56), fear of falling-related psychosocial variables (rs = |.24-.44|), and demographic characteristics (rpb = |.27-.32|). Test-retest reliability was good to excellent (ICC = .65-.91). Sensitivity to change was excellent for the LSA-CI composite score (SRM = .80) and small to moderate for the LSA-CI subscores (SRM = .35-.60). A completion rate of 100% and a mean completion time of 4.1 min) documented good feasibility. DISCUSSION AND IMPLICATIONS: The LSA-CI represents a valid, reliable, sensitive, and feasible interview-based life-space assessment tool in multimorbid older persons with CI.

Performance and reliability of the Lower Quarter Y Balance Test in healthy adolescents from grade 6 to 11.

BACKGROUND: The Lower Quarter Y Balance Test (YBT-LQ) has been widely used in the field to assess dynamic balance performance in various populations. However, no study has demonstrated test-retest reliability of the YBT-LQ in adolescents including several age cohorts, even though reliability is necessary to provide repeatable performance data. OBJECTIVE: Thus, we examined test-retest reliability of the YBT-LQ in healthy adolescents. METHODS: In a school setting, 178 secondary school students (93 female, 85 male) in sixth to eleventh grades (11-19 years) performed the YBT-LQ twice, 7 days apart. Normalized maximal reach distances (% leg length) for all three directions (i.e., anterior, posterolateral, posteromedial) and both legs and the composite score were used as outcome measures. Intraclass correlation coefficient (ICC3,1) and standard error of measurement (SEM) were calculated to assess relative and absolute test-retest reliability, respectively. Practical relevance of the YBT-LQ was determined by calculating the minimal detectable change (MDC95%). RESULTS: Irrespective of grade, test-retest reliability for all distances reached was predominately "excellent" (i.e., ICC3,1 > 0.75) and the rather small SEM values ranged from 1.77 to 5.81%. Depending on grade and reach direction, MDC values of 4.90 to 16.10% represent the minimum amount of change needed to identify clinically relevant effects in repeated measurements of the YBT-LQ performance. CONCLUSIONS: The observed values suggest that the YBT-LQ is a reliable test and suitable to detect changes of dynamic balance performance in healthy adolescents from grade six to eleven (i.e., aged 11-19 years).

Cut-off for the Life-Space Assessment in persons with cognitive impairment.

BACKGROUND: A version of the Life-Space Assessment in persons with cognitive impairment (LSA-CI) has recently been developed. AIMS: To establish a cut-off value for the newly developed Life-Space Assessment in persons with cognitive impairment (LSA-CI). METHODS: In a cross-sectional study including 118 multimorbid, older persons with cognitive impairment, life-space mobility (LSM) was documented by the LSA-CI. The analysis was rationalized by Global Positioning System (GPS)-based measures of spatial distance from home. A receiver-operating characteristic (ROC) curve was created and the cut-off point for the LSA-CI was identified with the Youden's Index. RESULTS: ROC curve analysis indicated a critical value of 26.75 (within a range of 0-90) to differentiate between low and high LSM with a sensitivity of 78.1% and specificity of 84.2%. DISCUSSION: Diagnostic interpretation of the ROC curves revealed that low and high LSM groups can be differentiated with the proposed cut-off. CONCLUSIONS: The proposed LSA-CI cut-off score can be recommended to tailor clinical interventions and evaluate change over time.

Associations Between Types of Balance Performance in Healthy Individuals Across the Lifespan: A Systematic Review and Meta-Analysis.

Background: The objective of this systematic review and meta-analysis was to quantify and statistically compare correlations between types of balance performance in healthy individuals across the lifespan. Methods: Literature search was performed in the electronic databases PubMed, Web of Science, and SPORTDiscus. Studies were included if they investigated healthy individuals aged ≥6 years and reported measures of static/dynamic steady-state, proactive, and/or reactive balance. The included studies were coded as follows: age group, gender, and balance type, test, parameter. Pearson's correlation coefficients were extracted, transformed (i.e., Fisher's z-transformed r z -value), aggregated (i.e., weighted mean r z -value), back-transformed to r-values, classified according to their magnitude, and statistically compared. The methodological quality of each study was assessed using the Appraisal tool for Cross-Sectional Studies. Results: We detected twenty-six studies that examined associations between types of balance and exclusively found small-sized correlations, irrespective of the age group considered. More specifically, the weighted mean r z-values amounted to 0.61 (back-transformed r-value: 0.54) in old adults for the correlation of dynamic steady-state with proactive balance. For correlations between dynamic and static steady-state balance, the weighted mean r z-values amounted to 0.09 in children (r-value: 0.09) and to 0.32 in old adults (r-value: 0.31). Further, correlations of proactive with static steady-state balance revealed weighted mean r z-values of 0.24 (r-value: 0.24) in young adults and of 0.31 (r-value: 0.30) in old adults. Additionally, correlations between reactive and static steady-state balance yielded weighted mean r z-values of 0.21 (r-value: 0.21) in young adults and of 0.19 (r-value: 0.19) in old adults. Moreover, significantly different correlation coefficients (z = 8.28, p < 0.001) were only found for the association between dynamic and static steady-state balance in children (r = 0.09) compared to old adults (r = 0.31). Lastly, we detected trivial to considerable heterogeneity (i.e., 0% ≤ I2 ≤ 83%) between studies. Conclusions: Our systematic review and meta-analysis showed exclusively small-sized correlations between types of balance performance across the lifespan. This indicates that balance performance seems to be task-specific rather than a "general ability." Further, our results suggest that for assessment/training purposes a test battery/multiple exercises should be used that include static/dynamic steady-state, proactive, and reactive types of balance. Concerning the observed significant age differences, further research is needed to investigate whether they are truly existent or if they are caused by methodological inconsistencies.

Single- and Dual-Task Balance Training Are Equally Effective in Youth.

Due to maturation of the postural control system and secular declines in motor performance, adolescents experience deficits in postural control during standing and walking while concurrently performing cognitive interference tasks. Thus, adequately designed balance training programs may help to counteract these deficits. While the general effectiveness of youth balance training is well-documented, there is hardly any information available on the specific effects of single-task (ST) versus dual-task (DT) balance training. Therefore, the objectives of this study were (i) to examine static/dynamic balance performance under ST and DT conditions in adolescents and (ii) to study the effects of ST versus DT balance training on static/dynamic balance under ST and DT conditions in adolescents. Twenty-eight healthy girls and boys aged 12-13 years were randomly assigned to either 8 weeks of ST or DT balance training. Before and after training, postural sway and spatio-temporal gait parameters were registered under ST (standing/walking only) and DT conditions (standing/walking while concurrently performing an arithmetic task). At baseline, significantly slower gait speed (p < 0.001, d = 5.1), shorter stride length (p < 0.001, d = 4.8), and longer stride time (p < 0.001, d = 3.8) were found for DT compared to ST walking but not standing. Training resulted in significant pre-post decreases in DT costs for gait velocity (p < 0.001, d = 3.1), stride length (-45%, p < 0.001, d = 2.4), and stride time (-44%, p < 0.01, d = 1.9). Training did not induce any significant changes (p > 0.05, d = 0-0.1) in DT costs for all parameters of secondary task performance during standing and walking. Training produced significant pre-post increases (p = 0.001; d = 1.47) in secondary task performance while sitting. The observed increase was significantly greater for the ST training group (p = 0.04; d = 0.81). For standing, no significant changes were found over time irrespective of the experimental group. We conclude that adolescents showed impaired DT compared to ST walking but not standing. ST and DT balance training resulted in significant and similar changes in DT costs during walking. Thus, there appears to be no preference for either ST or DT balance training in adolescents.

Effects of Single Compared to Dual Task Practice on Learning a Dynamic Balance Task in Young Adults.

Background: In everyday life, people engage in situations involving the concurrent processing of motor (balance) and cognitive tasks (i.e., "dual task situations") that result in performance declines in at least one of the given tasks. The concurrent practice of both the motor and cognitive task may counteract these performance decrements. The purpose of this study was to examine the effects of single task (ST) compared to dual task (DT) practice on learning a dynamic balance task. Methods: Forty-eight young adults were randomly assigned to either a ST (i.e., motor or cognitive task training only) or a DT (i.e., motor-cognitive training) practice condition. The motor task required participants to stand on a platform and keeping the platform as close to horizontal as possible. In the cognitive task, participants were asked to recite serial subtractions of three. For 2 days, participants of the ST groups practiced the motor or cognitive task only, while the participants of the DT group concurrently performed both. Root-mean-square error (RMSE) for the motor and total number of correct calculations for the cognitive task were computed. Results: During practice, all groups improved their respective balance and/or cognitive task performance. With regard to the assessment of learning on day 3, we found significantly smaller RMSE values for the ST motor (d = 1.31) and the DT motor-cognitive (d = 0.76) practice group compared to the ST cognitive practice group but not between the ST motor and the DT motor-cognitive practice group under DT test condition. Further, we detected significantly larger total numbers of correct calculations under DT test condition for the ST cognitive (d = 2.19) and the DT motor-cognitive (d = 1.55) practice group compared to the ST motor practice group but not between the ST cognitive and the DT motor-cognitive practice group. Conclusion: We conclude that ST practice resulted in an effective modulation of the trained domain (i.e., motor or cognitive) while only DT practice resulted in an effective modulation of both domains (i.e., motor and cognitive). Thus, particularly DT practice frees up central resources that were used for an effective modulation of motor and cognitive processing mechanisms.

Associations Between Practice-Related Changes in Motor Performance and Muscle Activity in Healthy Individuals: A Systematic Review.

BACKGROUND: A well-learned motor skill is characterized by the efficient activation of muscles that are involved in movement execution. However, it is unclear if practice-related changes in motor performance correlate with those in quantitative markers of muscle activity and if so, whether the association is different with respect to the investigated muscle (i.e., agonist and antagonist) and quantitative myoelectric parameter. Thus, we conducted a systematic review and characterized associations between practice-related changes in motor performance and muscle activity in healthy individuals. METHODS: A computerized systematic literature search was performed in the electronic databases PubMed, Web of Science, and SPORTDiscus up to September 2017 to capture all relevant articles. A systematic approach was applied to evaluate the 1670 articles identified for initial review. Studies were included only if they investigated healthy subjects aged 6 years and older and tested at least one measure of motor performance (e.g., error score, movement time) and quantitative muscle activity (i.e., amplitude domain: iEMG [integrated electromyography], RMS [root mean square]; time domain: duration of muscle activity, time to peak muscle activation). In total, 24 studies met the inclusionary criteria for review. The included studies were coded for the following criteria: age, learning task, practice modality, and investigated muscles (i.e., agonist and antagonist). Correlation coefficients for the relationship of motor performance changes with changes in electromyography (EMG) amplitude, and duration were extracted, transformed (i.e., Fisher's z-transformed rz value), aggregated (i.e., weighted mean rz value), and back-transformed to r values. To increase sample size, we additionally extracted pre and post practice data for motor performance and myoelectric variables and calculated percent change values as well as associations between both. Correlations were classified according to their magnitude (i.e., small r ≤ 0.69, medium r ≤ 0.89, large r ≥ 0.90). RESULTS: Five studies reported correlation coefficients for the association between practice-related alterations in motor performance and EMG activity. We found small associations (range r = 0.015-0.50) of practice-related changes in motor performance with measures of agonist and antagonist EMG amplitude and duration. A secondary analysis (17 studies) that was based on the calculation of percent change values also revealed small correlations for changes in motor performance with agonist (r = - 0.25, 11 studies) and antagonist (r = - 0.24, 7 studies) EMG amplitude as well as agonist (r = 0.46, 8 studies) and antagonist (r = 0.29, 5 studies) EMG duration. CONCLUSIONS: Our systematic review showed small-sized correlations between practice-related changes in motor performance and agonist and antagonist EMG amplitude and duration in healthy individuals. These findings indicate that practice-related changes can only partly be explained by quantitative myoelectric measures. Thus, future studies investigating biomechanical mechanisms of practice-related changes in motor performance should additionally include qualitative measures of muscle activity (e.g., timing of muscle activity, level of coactivation) and other biomechanical variables (i.e., kinetics, kinematics).

Development of a home-based training program for post-ward geriatric rehabilitation patients with cognitive impairment: study protocol of a randomized-controlled trail.

BACKGROUND: Geriatric patients with cognitive impairment (CI) show an increased risk for a negative rehabilitation outcome and reduced functional recovery following inpatient rehabilitation. Despite this obvious demand, evidence-based training programs at the transition from rehabilitation to the home environments are lacking. The aim of this study is to evaluate the efficacy of a feasible and cost-effective home-based training program to improve motor performance and to promote physical activity, specifically-tailored for post-ward geriatric patients with CI. METHODS: A sample of 101 geriatric patients with mild to moderate stage CI following ward-based rehabilitation will be recruited for a blinded, randomized controlled trial with two arms. The intervention group will conduct a 12 week home-based training, consisting of (1) Exercises to improve strength/power, and postural control; (2) Individual walking trails to enhance physical activity; (3) Implementation of patient-specific motivational strategies to promote behavioral changes. The control group will conduct 12 weeks of unspecific flexibility exercise. Both groups will complete a baseline measurement before starting the program, at the end of the intervention, and after 24 weeks for follow-up. Sensor-based as well as questionnaire-based measures will be applied to comprehensively assess intervention effects. Primary outcomes document motor performance, assessed by the Short Physical Performance Battery, and level of physical activity (PA), as assessed by duration of active episodes (i.e., sum of standing and walking). Secondary outcomes include various medical, psycho-social, various PA and motor outcomes, including sensor-based assessment as well as cost effectiveness. DISCUSSION: Our study is among the first to provide home-based training in geriatric patients with CI at the transition from a rehabilitation unit to the home environment. The program offers several unique approaches, e.g., a comprehensive and innovative assessment strategy and the integration of individually-tailored motivational strategies. We expect the program to be safe and feasible in geriatric patients with CI with the potential to enhance the sustainability of geriatric rehabilitation programs in patients with CI. TRIAL REGISTRATION: International Standard Randomized Controlled Trial (# ISRCTN82378327 ). Registered: August 10, 2015.