Peak leg muscle power, peak VO2 and its correlates with physical activity in 57 to 70-year-old women.

The two aims of this study were first to measure short-term muscle power (STMP) by means of a cycling force-velocity test (cycling peak power: CPP) and a vertical jump test (jumping peak performance: JPP) and second, to examine the relationships between physical activity (PA) level, peak oxygen uptake (peak VO2) and STMP in healthy elderly women. Twenty-three independent community-dwelling elderly women (mean age: 64+/-4.4) performed on separate days, a peak oxygen uptake test on cycle ergometer, a cycling force-velocity test and a vertical jump test. A questionnaire (QUANTAP) was used to assess lifespan exercise habits. Four indices expressed in kJ day(-1) kg(-1) were calculated. Two indices represented average past PA level: 1/quantity of habitual physical activity (QHPA), 2/quantity of sports activities (QSA). Two indices represented the actual PA level: 3/actual quantity of habitual physical activity (AQHPA), 4/actual quantity of sports activities (AQSA). CPP (6.3+/-1.2 W kg(-1)) was closely correlated to JPP (14.8+/-3.4 cm) (r=0.80, P<0.001). AQHPA and AQSA were only positively associated with peak VO2 (ml min(-1) kg(-1)) (r=0.49; r=0.50, P<0.05, respectively). Past PA level was not related to fitness measurements. Results show that in this population: (1) jumping peak performance was closely related to CPP measured in the laboratory; (2) the cardio-respiratory fitness was related to the actual habitual physical activity level; (3) only age and anthropometric variables explained the actual performances in multivariate analysis.

Validity of a V.O2 max prediction equation of the 2-km walk test in female seniors.

Walking is a useful exercise mode for most adults due to its general ease, acceptability, and safety. Therefore, many field tests based on performance in walking have been developed to predict V.O (2 max). Even if these tests are much easier to perform than laboratory tests, field tests have to be valid. The objective of the paper was to explore the accuracy and bias of a V.O (2 max) prediction equation of the 2-km Walk Test, in an active female senior group (n=18, mean age: 66.1+/-4.4). V.O (2 max) (l . min (-1)) was measured during cycle ergometry by direct gas analysis from a maximal test (step: 30 W, time: 2 min 30). V.O (2 max) related to body mass was then calculated (ml . min (-1) . kg (-1)). Subjects completed also the 2-km Walk Test (UKK Institute). V.O (2 max) (ml . min (-1) . kg (-1)) was then predicted from age, sex, body mass index, heart rate, and walking time measured during the 2-km Walk Test. Predicted V.O (2 max) and measured V.O (2 max) were highly correlated (r=0.63, p<0.01). Predicted V.O (2 max) (20.5+/-6.1 ml . min (-1) . kg (-1)) was not significantly different from measured V.O (2 max) (18.7+/-3.4 ml . min (-1) . kg (-1)). Prediction equation bias with its 95 % limits of agreement was - 1.8+/-4.8 ml . min (-1) . kg (-1) with a coefficient of variation of 24.2 %. In an active female senior population, the 2-km Walk Test offers a fairly accurate V.O (2 max) prediction. The training and learning effects can be neglected because when the test was repeated no significant bias was observed between the two trials.