Accelerometer Determined Physical Activity in Older Women: A Descriptive Study

Abstract

No relationships reported)PURPOSE: To evaluate the reliability of 2 field tests and one non-exercise questionnaire on the estimation of VO2max and their sensibility to a 5-month training program in a sample of older adults. METHODS:Twenty healthy older sedentary adults from 60 to 80 years, randomly assigned to an Aerobic and Strength training program or a Stretching program, were evaluated for their cardiorespiratory fitness before and after the 5-month training programs. VO2max was evaluated at baseline (T1) by a nonexercise test model (Jurca et al., 2005) and at baseline, after 3 months (T2) and again after 5 months (T3) by the Rockport 1-mile walk test (Kline et al., 1987) and the self-paced Step test (Petrella et al., 1998). Reliability of the 3 tests at T1 was estimated by Cronbach alpha. Differences between VO2max measures at T1 and sensibility to the 2 training programs were assessed by ANOVAs with repeated measures. Significantly increase in VO2max from T1 to T3 was expected only for the Aerobic group but not for the Stretching group. RESULTS:The test of reliability revealed that the 3 tests were highly reliable and represented measures of the same construct (Cronbach α = .898). At T1, VO2max of all participants, estimated from the Rockport walk test (19.6±6 ml.kg -1 .min -1 ) and from the questionnaire of Jurca and al. (19.5±5 ml.kg -1 .min -1 ) did not differ significantly. However, the Step test overestimated VO2max (25.6±5 ml.kg -1 .min -1 ) comparatively to the 2 other tests (p<0.05). VO2max estimated with the Rockport walk test significantly increased from T1 to T2 and T3 (p<0.05), but to the same magnitude for the 2 training groups (p=0.19). Only the Step test was able to detect a significant Group by Session interaction (p<0.05). VO2max estimated with the Step test, significantly increased from T1 to T3 only for the Aerobic group (p<0.05), but did not significantly vary for the Stretching group (p>0.05). CONCLUSION:Although this study did not provide direct measures of VO2max, it seems that the Step test overestimated actual VO2max in our sample of healthy older adults. Moreover, only the Step test was sensitive to discriminate the effects of 2 training programs differing in exercise intensity. More work is needed to clearly establish what kind of VO2max estimation test is valuable for epidemiological or interventional studies involving older adults. (No relationships reported)PURPOSE: The aim of this study was to analyze the correlation with electromyography (EMG) responses of vastus lateralis muscle and human body to withstand the acceleration of gravity in different whole-body vibration frequencies for Middle-Aged and Elderly People. METHODS: 15 people (age, 56.9±3.6 years; height, 162.5±11.1 cm; weight, 68.4±5.6 kg) participated in the study. Vibration treatment was administered while standing on a vibrating platform with knees bent at 100 0 (LV-1000, X-train). EMG root mean square (rms) and acceleration of gravity (G) (force plate, AMTI) on human loading was recorded for 60 seconds while s...