The effect of muscle fatigue on wrist joint position sense in healthy adults.

STUDY DESIGN: Pretest and posttest experimental study. INTRODUCTION: The effect of muscle fatigue on wrist joint position sense (JPS) has yet to be determined. PURPOSE OF THE STUDY: The primary aim was to determine whether muscle fatigue affects wrist JPS in healthy adults. The secondary aims were to compare the effect of muscle fatigue on younger and older adults JPS and determine the association between JPS rate of change and total muscle fatigue (TMF) rates postexercise. METHODS: Forty male and female healthy adults were assigned into younger (18-40 years) and older (41-65 years) groups. Preexercise and postexercise testing consisted of active wrist JPS, handgrip, and wrist extensor strength assessments. Muscle fatigue was induced via a calibrated gripper and wrist extension dumbbell exercises. Dependent variables were the JPS rate of change (ie, preexercise and postexercise), TMF rate (ie, grip and wrist extension average strength decline), and Borg Rating of Perceived Exertion scale scores. RESULTS: Postexercise wrist JPS test scores were significantly higher than preexercise. Exercises induced statistically significant TMF rates and Borg Rating of Perceived Exertion scores among all participants. No statistically significant age-group differences on JPS rate of change, and TMF rate was found. A statistically significant mild correlation (r = 0.425) existed between JPS rate of change and TMF rates. DISCUSSION: Postexercise fatigue significantly impairs wrist JPS in both younger and older adults. On average, an 18% muscle strength decline led to 215% wrist JPS deficit. CONCLUSIONS: Significant wrist proprioception deficits persist for ≤5 min following exertional exercises, regardless of age level.

The Rehabilitation Enhancing Aging Through Connected Health Prehabilitation Trial.

OBJECTIVE: To evaluate the proof of concept of an innovative model of physical therapy Rehabilitation Enhancing Aging through Connected Health (REACH) and evaluated its feasibility and effect on physical function and health care utilization. DESIGN: Quasi-experimental 12-month clinical trial. SETTING: Two outpatient rehabilitation centers. PARTICIPANTS: Community-dwelling older primary care patients with a treatment arm undergoing the intervention (n=75; mean age=77±5.9y; 54% women) and propensity matched controls derived from a longitudinal cohort study (n=430; mean age=71±7.0y; 68% women) using identical recruitment criteria (N=505). INTERVENTION: Combined outpatient and home PT augmented with a commercially available app and computer tablet. MEASUREMENTS: Primary outcomes included a feasibility questionnaire, exercise adherence, self-reported function, and the Short Physical Performance Battery (SPPB). Secondary outcomes included the rates of emergency department (ED) visits and hospitalizations. RESULTS: Among REACH participants, we observed a 9% dropout rate. After accounting for dropouts, with propensity matching, n=68 treatments and n=100 controls were analyzed. Over the 12-month study duration, 85% of participants adhered to the exercise program an average of 2 times a week and evaluated the treatment experience favorably. In comparison to controls, after 1 year of treatment and within multivariable regression models, REACH participants did not manifest a significant difference in patient reported function (group x time effect 1.67 units, P=.10) but did manifest significant differences in SPPB (group x time effect 0.69 units, P=.03) and gait speed (group x time effect .08m/s, P=.02). In comparison to controls, after 1 year, the rate of ED visits (group x time treatment rate=0.27, P<.004) were significantly reduced, but a significant reduction in hospitalizations was not observed. CONCLUSION: The REACH intervention is feasible and has proof of concept in preventing functional decline and favorably affecting health care utilization. Evaluation on a larger scale is warranted.

The rehabilitation enhancing aging through connected health (REACH) study: study protocol for a quasi-experimental clinical trial.

BACKGROUND: Mobility limitations among older adults increase the risk for disability and healthcare utilization. Rehabilitative care is identified as the most efficacious treatment for maintaining physical function. However, there is insufficient evidence identifying a healthcare model that targets prevention of mobility decline among older adults. The objective of this study is to evaluate the preliminary effectiveness of a physical therapy program, augmented with mobile tele-health technology, on mobility function and healthcare utilization among older adults. METHODS: This is a quasi-experimental 12-month clinical trial conducted within a metropolitan-based healthcare system in the northeastern United States. It is in parallel with an existing longitudinal cohort study evaluating mobility decline among community-dwelling older adult primary care patients over one year. Seventy-five older adults (≥ 65-95 years) are being recruited using identical inclusion/exclusion criteria to the cohort study. Three aims will be evaluated: the effect of our program on 1) physical function, 2) healthcare utilization, and 3) healthcare costs. Changes in patient-reported function over 1 year in those receiving the intervention (aim 1) will be compared to propensity score matched controls (N = 150) from the cohort study. For aims 2 and 3, propensity scores, derived from logistic regression model that includes demographic and diagnostic information available through claims and enrollment information, will be used to match treatment and control patients in a ratio of 1:2 or 1:3 from a Medicare Claims Registry derived from the same geographic region. The intervention consists of a one-year physical therapy program that is divided between a combination of outpatient and home visits (6-10 total visits) and is augmented on a computerized tablet using of a commercially available application to deliver a progressive home-based exercise program emphasizing lower-extremity function and a walking program. DISCUSSION: Incorporating mobile health into current healthcare models of rehabilitative care has the potential to decrease hospital visits and provide a longer duration of care. If the hypotheses are supported and demonstrate improved mobility and reduced healthcare utilization, this innovative care model would be applicable for optimizing the maintenance of functional independence among community-dwelling older adults. TRIAL REGISTRATION: ClinicalTrial.gov Identifier: NCT02580409 (Date of registration October 14, 2015).

Reliability, Validity, and Minimal Detectable Change of Four-Step Stair Climb Power Test in Community-Dwelling Older Adults.

BACKGROUND: Stair climb power is an important clinical measure of lower-extremity power. The stair climb power test (SCPT) was validated by requiring individuals to climb a full flight of stairs. A 4-step SCPT (4SCPT) would be more clinically feasible and easier to perform, yet its reliability and validity are unknown. OBJECTIVE: To evaluate reliability, validity, and minimal detectable change of 4SCPT among community-dwelling older adults. DESIGN: This study is a cross-sectional analysis of baseline data from a clinical trial. METHODS: Fifty older adults ≥65 years of age, at risk for mobility decline, consented to participate in this ancillary study. Test-retest reliability was derived from 2 measurements within each participant measured by a single assessor. Pearson correlation analyses among leg power measures (4SCPT, SCPT, single leg press power at 40% and 70% of the 1-repetition maximum [SLP40, SLP70]) were performed. Separate multivariate linear regressions were conducted evaluating the associations between each leg power measure and 2 mobility outcomes, the Short Physical Performance Battery (SPPB) and habitual gait speed (HGS). Minimal detectable change was based on a 90% confidence interval (MDC 90 ). RESULTS: The 4SCPT had excellent test-retest reliability (ICC(2,1) = 0.951), and strong correlation with SCPT, SLP40, and SLP70 ( r = 0.85-0.96). The 4SCPT explained a greater amount of variance in the SPPB (R 2 = 0.31) than other leg power measurements (R 2 = 0.23-0.25). The 4SCPT (R 2 = 0.41) and SCPT (R 2 = 0.42) described equivalent amounts of variance in HGS, and greater than that with SLP40 (R 2 = 0.28) and SLP70 (R 2 = 0.30). The MDC 90 for 4SCPT was 44.0 watts. LIMITATIONS: This was a cross-sectional analysis within a small, nonrepresentative sample. Interrater reliability was not evaluated. CONCLUSIONS: The 4SCPT shows scientific promise as a valid and reliable leg power measurement among community-dwelling older adults.