Rethinking walkability and developing a conceptual definition of active living environments to guide research and practice.

BACKGROUND: Walkability is a popular term used to describe aspects of the built and social environment that have important population-level impacts on physical activity, energy balance, and health. Although the term is widely used by researchers, practitioners, and the general public, and multiple operational definitions and walkability measurement tools exist, there are is no agreed-upon conceptual definition of walkability. METHOD: To address this gap, researchers from Memorial University of Newfoundland hosted "The Future of Walkability Measures Workshop" in association with researchers from the Canadian Urban Environmental Health Research Consortium (CANUE) in November 2017. During the workshop, trainees, researchers, and practitioners worked together in small groups to iteratively develop and reach consensus about a conceptual definition and name for walkability. The objective of this paper was to discuss and propose a conceptual definition of walkability and related concepts. RESULTS: In discussions during the workshop, it became clear that the term walkability leads to a narrow conception of the environmental features associated with health as it inherently focuses on walking. As a result, we suggest that the term Active Living Environments, as has been previously proposed in the literature, are more appropriate. We define Active Living Environments (ALEs) as the emergent natural, built, and social properties of neighbourhoods that promote physical activity and health and allow for equitable access to health-enhancing resources. CONCLUSIONS: We believe that this broader conceptualization allows for a more comprehensive understanding of how built, natural, and social environments can contribute to improved health for all members of the population.

Reliability and Validity of Commercially Available Wearable Devices for Measuring Steps, Energy Expenditure, and Heart Rate: Systematic Review.

BACKGROUND: Consumer-wearable activity trackers are small electronic devices that record fitness and health-related measures. OBJECTIVE: The purpose of this systematic review was to examine the validity and reliability of commercial wearables in measuring step count, heart rate, and energy expenditure. METHODS: We identified devices to be included in the review. Database searches were conducted in PubMed, Embase, and SPORTDiscus, and only articles published in the English language up to May 2019 were considered. Studies were excluded if they did not identify the device used and if they did not examine the validity or reliability of the device. Studies involving the general population and all special populations were included. We operationalized validity as criterion validity (as compared with other measures) and construct validity (degree to which the device is measuring what it claims). Reliability measures focused on intradevice and interdevice reliability. RESULTS: We included 158 publications examining nine different commercial wearable device brands. Fitbit was by far the most studied brand. In laboratory-based settings, Fitbit, Apple Watch, and Samsung appeared to measure steps accurately. Heart rate measurement was more variable, with Apple Watch and Garmin being the most accurate and Fitbit tending toward underestimation. For energy expenditure, no brand was accurate. We also examined validity between devices within a specific brand. CONCLUSIONS: Commercial wearable devices are accurate for measuring steps and heart rate in laboratory-based settings, but this varies by the manufacturer and device type. Devices are constantly being upgraded and redesigned to new models, suggesting the need for more current reviews and research.

Changes in arterial distensibility and flow-mediated dilation after acute resistance vs. aerobic exercise.

Previous research has shown significantly lower arterial distensibility (AD) after resistance exercise (RE) yet higher AD after aerobic exercise (AE). These changes may be related to exercise-induced differences in vasodilatory capacity. The purpose of this study was to investigate the vasodilatory and AD responses to acute AE and RE. Forearm blood flow (FBF) during reactive hyperemia (RH) was assessed before and 60 minutes after exercise, whereas aortic and femoral pulse wave velocity was measured as an index of arterial stiffness pre, 40, and 60 minutes after an acute bout of AE (30-minute leg ergometry at 65% of VO2peak) and RE (3 sets, 10 reps; upper and lower body at 65% 1 repetition maximum) in 10 male subjects (24.9 ± 0.86 years). Area under the curve (AUC) was employed to determine differences in flow. After the intervention, we found that central pulse wave velocity decreased 8% after AE and remained depressed at this level through 60 minutes of observation, whereas RE increased central pulse wave velocity 9.8% from pre to 40 and 60 minutes postexercise. Area under the curve for FBF-RH significantly increased 38% after RE, yet there was no significant change after AE. Forearm vasodilatory capacity increased after acute RE but not after acute AE. This suggests that changes in AD may be disassociated from changes in vasodilatory capacity after acute exercise. Further, in a direct comparison of RE vs. AE, we have shown that RE has greater increases in limb blood flow and augments postexercise hypotension greater at 40 minutes postexercise when compared to AE.