A comparison of physical activity (PA) assessment tools across levels of frailty.
OBJECTIVE
Determine which PA assessment tools are most closely related to frailty and whether PA is different across levels of frailty.


METHODS
Fifty community-dwelling Greek older women (63-90 years) participated in this study. PA was measured objectively over 10h using an accelerometer, a heart rate (HR) monitor, a portable electromyography (EMG) unit, and a global positioning system (GPS) and subjectively using the short version of the Minnesota Leisure Time Activity Questionnaire (MLTAQ). Participants were divided into three tertiles based on level of frailty as calculated from a Frailty Index (FI): low FI group (<0.17 FI); intermediate FI group (0.17-0.38 FI); and high FI group (>0.38 FI).


RESULTS
Accelerometer step counts had the strongest correlation with frailty and were different across levels of frailty. The percentage of time engaged in PA was 31±15% when PA was determined using an accelerometer. Forty-five percent of the variability in the FI was explained by a combination of PA assessment tools including; accelerometer, EMG, GPS, and MLTAQ. The individual contribution of EMG determined activity from the biceps brachii (BB) to the FI prediction was 16%. Accelerometer contributed an additional 10% and time engaged in PA, as assessed with the MLTAQ, added an additional 6% to the prediction of FI score.


CONCLUSIONS
PA assessment tools, when used in combination, provide important information about the PA accumulation of older women across levels of frailty.
School of Health and Exercise Sciences, University of British Columbia Okanagan, 3333 University Way, Kelowna, BC, Canada. otheou@alumni.uwo.ca
Olga
O
Theou
Jennifer M
JM
Jakobi
Anthony A
AA
Vandervoort
Gareth R
GR
Jones
D000368:Aged; D000369:Aged, 80 and over; D004576:Electromyography; D005260:Female; D016330:Frail Elderly; D015577:Geriatric Assessment / Q000379:methods; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D012111:Residence Characteristics; D011795:Surveys and Questionnaires