Assessment of the MyWellness Key accelerometer in people with type 2 diabetes.
Accelerometers are designed to measure physical activity (PA) objectively. The MyWellness Key (MWK) accelerometer has been validated primarily in younger, normal-weight populations. The aims of this study were to examine the accuracy of the MWK against directly measured lab-based exercise and free-living PA in people with type 2 diabetes, many of whom are older and overweight or obese. Thirty-five participants with type 2 diabetes completed the protocol, which included a laboratory-based session and a free-living phase. In the laboratory visit, participants completed a structured treadmill protocol wearing MWKs on each hip (all subjects) and bra cup (women only). The speed where each MWK switched from recording light- to moderate-intensity activity was determined for each MWK worn. In the free-living phase, participants wore the MWK for all waking hours for 2 weeks, and recorded exercise in PA diaries immediately after each exercise session. The mean cut-points between low ("Free") and moderate ("Play") intensity for the right and left waist-worn MWKs were 4.1 ± 0.5 km/h and 5.0 ± 0.9 km/h for the bra-mounted MWK; ideal cut-point would be 4.0 km/h. In the free-living phase, the Spearman correlation between PA according to PA diary and the waist-worn MWK was 0.81 (95% confidence interval (CI): 0.76, 0.85; P < 0.001), but only 0.66 (95% CI: 0.53, 0.77; P < 0.001) when on the bra. In conclusion, the waist-worn MWK measured PA volume accurately, and was acceptably accurate at discriminating between low- and moderate-intensity PA in people with type 2 diabetes. The MWK underestimated PA volume and intensity when worn on a bra.
a Faculty of Kinesiology, University of Calgary, Calgary, AB T2N 1N4, Canada.
Samantha Kate
SK
McGinley
b Department of Cardiovascular and Respiratory Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada.
Marni J
MJ
Armstrong
c Alberta Health Services, Department of Cancer Epidemiology and Prevention Research, 5th floor, Holy Cross Centre, Box ACB, 2210 - 2nd St. SW, Calgary, AB T2S 3C3, Canada.
Farah
F
Khandwala
d Centre for Human Performance and Sport, Medway Campus, Greenwich University, Kent ME4 4TB, UK.
Silvano
S
Zanuso
e Departments of Medicine, Cardiac Sciences, and Community Health Sciences, Cumming School of Medicine, Faculties of Medicine and Kinesiology, Division of Endocrinology and Metabolism, University of Calgary, RRDTC, 1820 Richmond Road SW, Room 1898, Calgary, AB T2T 5C7, Canada.
Ronald J
RJ
Sigal
D056044:Actigraphy / Q000295:instrumentation*; D000203:Activities of Daily Living; D000368:Aged; D003020:Clothing; D003924:Diabetes Mellitus, Type 2 / Q000175:diagnosis / Q000503:physiopathology*; D004867:Equipment Design; D005080:Exercise Test; D005260:Female; D006304:Health Status; D006339:Heart Rate; D006801:Humans; D008297:Male; D008422:Materials Testing; D008875:Middle Aged; D009043:Motor Activity; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D013997:Time Factors
MyWellness Key; accelerometer; accéléromètre; activité physique; diabète de type 2; exercice physique; exercise; physical activity; type 2 diabetes; validation