Individually tailored, Internet-mediated PA interventions are an effective way to significantly increase PA in older adults.

There are many research studies documenting the validity and intervention effectiveness of consumer-WPAMs; evidence is emerging on the health benefits linked to use of such devices. Future work on the long-term effects of consumer-WPAMs on behavior and health is warranted, and prospects appear exciting as wearable technology advances and adoption increases.

This study examined the effects of a 12 week, treadmill-based, run sprint interval training (SIT) protocol compared with that of a moderate-intensity continuous training (MICT) protocol in healthy, inactive, overweight/obese women, on cardiovascular disease risk factors. After random assignment, the SIT group completed 4-10 × 30 s maximal sprints, with a 4 min active recovery between sprints, and the MICT group completed 30-60 min at moderate intensity (45-55% heart rate reserve (HRR)). The rate of perceived exertion (RPE) was recorded for each session, and perceived enjoyment was quantified every 3 weeks. Clinical and fitness testing were completed at baseline, 6 weeks, and 12 weeks. Twelve female participants (age: 34.1 ± 6.1; body mass index (BMI): 31.3 ± 6.8; VO 2peak : 27.0 ± 6.2) completed the intervention. There were significant main effects for time for VO 2peak (p = 0.001), body fat percentage (p = 0.001), and session RPE (p = 0.006). VO 2peak improved 20.7% in the SIT group (n = 5) and 24.4% in the MICT group (n = 7). Body fat percentage reduced by 1.7% in the SIT group and 2.6% in the MICT group. Perceived enjoyment was similarly high between the groups despite higher session RPE in the SIT group (p = 0.441). SIT training on a motor-driven treadmill elicits similar improvements in oxygen utilization and body composition as moderate-intensity training in this population.

Extrapolating these results, pedaling at a SSP for an hour while performing seated activities is equivalent to the net EE of walking 1.6 miles. Future home-based effectiveness and feasibility should be explored.

Introduction Field tests to estimate maximal oxygen consumption (VO2max) are an alternative to traditional exercise testing methods. Published field tests and their accompanying estimation equations account for up to 80% of the variance in VO2max with an error rate of ~4.5 ml.kg-1.min-1. These tests are limited to very specific age-range populations. The purpose of this study was to create and validate a series of easily administered walking and stepping field equations to predict VO2max across a range of healthy 18-79-year-old adults. Methods One-hundred-fifty-seven adults completed a graded maximal exercise test to assess VO2max. Five separate walking and three separate stepping tests of varying durations, number of stages, and intensities were completed. VO2max estimation equations were created using hierarchal multiple regression. Covariates including age, sex, body mass, resting heart rate, distance walked, gait speed, stepping cadence, and recovery heart rate were entered into each model using a stepwise approach. Each full model created had the same base model consisting of age, sex, and body mass. Validity of each model was assessed using a Jackknife cross-validation analysis, and percent bias and root mean square error (RMSE) were calculated. Results Base models accounted for ~72% of the total variance of VO2max. Full model variance ranged from ~79–83% and bias was minimal (<±1.0%) across models. RMSE for all models were approximately 4.5 ml.kg-1.min-1. Stepping tests performed better than walking tests by explaining ~2.5% more of the variance and displayed smaller RMSE. Conclusion All eight models accounted for a large percentage of VO2max variance (~81%) with a RMSE of ~4.5 ml.kg-1.min-1. The variance and level of error of models examined highlight good group mean prediction with greater error expected at the individual level. All the models perform similarly across a broad age range, highlighting flexibility in application of these tests to a more general population.

Objective Slow walking speed paired with increased energy cost is a strong predictor for mortality and disability in older adults but has yet to be examined in a heterogeneous sample (ie, age, sex, disease status). The aim of this study was to examine energy cost of slow and normal walking speeds among low-and normal-functioning adults. Design Adults aged 20-90 yrs were recruited for this study. Participants completed a 10-m functional walk test at a selfselected normal walking speed and were categorized as low functioning or normal functioning based on expected age-and sex-adjusted average gait speed. Participants completed two successive 3-min walking stages, at slower than normal and normal walking speeds, respectively. Gas exchange was measured and energy cost per meter (milliliter per kilogram per meter) was calculated for both walking speeds. Results Energy cost per meter was higher (P < 0.0001) in the low-functioning group (n = 76; female = 59.21%; mean ± SD age = 61.13 ± 14.68 yrs) during the slower than normal and normal (P < 0.0001) walking speed bouts compared with the normal-functioning group (n = 42; female = 54.76%; mean ± SD age = 51.55 ± 19.51 yrs). Conclusions Low-functioning adults rely on greater energy cost per meter of walking at slower and normal speeds. This has implications for total daily energy expenditure in low-functioning, adult populations.

Objective To determine classes of motor performance based on community deployable motor impairment and functional tests in a heterogeneous adult population. Design Sixteen tests of limb-specific and whole-body measures of motor impairment and function were obtained. Linear regression analysis was used to dichotomize performance on each test as falling within or outside the age- and sex-predicted values. Latent class analysis was used to determine 3 classes of motor performance. The chi-square test of association and the Fisher exact test were used for categorical variables, and analysis of variance and the Kruskal-Wallis test were used for continuous variables to evaluate the relationship between demographic characteristics and latent classes. Setting General community. Participants Individuals (N=118; 50 men) participated in the study. Quota sampling was used to recruit individuals who self-identified as healthy (n=44) or currently living with a preexisting chronic health condition, including arthritis (n=19), multiple sclerosis (n=18), Parkinson disease (n=17), stroke (n=18), or low functioning (n=2). Intervention Not applicable. Main Outcome Measure Latent classes of motor performance. Results Across the entire sample, 3 latent classes of motor performance were determined that clustered individuals with motor performance falling: (1) within predicted values on most of the tests (expected class), (2) outside predicted values on some of the tests (moderate class), and (3) outside predicted values on most of the tests (severe class).The ability to distinguish between the respective classes based on the percent chance of falling outside predicted values was achieved using the following community deployable motor performance tests: 10-meter walk test (22%, 80%, and 100%), 6-minute walk test (14.5%, 37.5%, and 100%), grooved pegboard test (23%, 38%, and 100%), and modified physical performance test (3%, 54%, and 96%). Conclusions In this heterogeneous group of adults, we found 3 distinct classes of motor performance, with the sample clustering into an expected test score group, a moderate test score deficiency group, and a severed test score deficiency group. Based on the motor performance tests, we established that community deployable, easily administered testing could accurately predict the established clusters of motor performance.

&lt;p&gt;The process of meandering in alluvial rivers is the result of spatial variability in erosion and deposition that systematically alternates from one side of the channel to the next along sequential meander bends. The localized erosion of outer banks, typically downstream of the bend apex, occurs due to an outward advection of high-momentum fluid leading to an asymmetric lateral distribution of streamwise velocity. Two primary mechanisms are responsible for the lateral flux of streamwise momentum within meander bends. The first is an increasing bed elevation along the inner bank in the form of a point bar that causes a shoaling effect, steering fluid mass and momentum from the inner bank toward the outer bank. The second mechanism is curvature-driven secondary circulation that leads to helical motion of flow through the bend and an outward advection of high-momentum near-surface flow. While these two mechanisms have been studied previously, their relative contribution to the net redistribution of momentum within a series of consecutive bends have not yet been fully documented. For this study, we obtained three-dimensional velocity measurements using a boat-mounted acoustic Doppler current profiler along regularly spaced cross-sections for six consecutive meander bends on the Pearl River (Louisiana, USA) during two different discharge conditions. Velocity data were processed using the Velocity Mapping Toolbox in Matlab, and calculations were performed to evaluate the lateral flux of streamwise momentum due to topographic steering and secondary circulation using the Rozovskii frame of reference. These momentum flux terms are systematically compared to spatial series of curvature, bed elevation, and channel width to elucidate the interactions between form and flow structure. Results show that lateral flux of streamwise momentum is primarily driven by topographic steering, and that values of momentum flux due to curvature-driven secondary circulation are on average an order of magnitude lower. The spatial pattern of these flux components through the bends show that momentum redistribution due to topographic steering is highest at the entrance to the bend, and momentum redistribution due to secondary circulation is typically highest downstream of the apex.&amp;#160; The results of this study emphasize the important role that interaction between process and form play in dynamics of natural meandering rivers.&amp;#160; Point bars form through spatial variations in bed-material transport capacity within curved channels, but, once in place, these bars reinforce their own persistence through their influence on the lateral redistribution of streamwise momentum.&amp;#160;&lt;/p&gt;