Habitual physical activity and peak anaerobic power in elderly women

The aim of this study was to investigate the relationship between maximal anaerobic power (Pmax) and corresponding optimal velocity (Vopt) and habitual physical activity (PA) on the one hand and with maximal oxygen consumption (VO2max) on the other hand, in elderly women. Twenty-nine community dwelling, healthy women aged 66-82 years participated in the study. PA was evaluated using the Questionnaire d'Activite Physique Saint-Etienne (QAPSE) and expressed using two QAPSE activity indices: mean habitual daily energy expenditure (MHDEE) and daily energy expenditure corresponding to leisure time sports activities (sports activity). The subjects' Pmax and Vopt were measured while they cycled on a friction-loaded non-isokinetic cycle ergometer. Pmax was expressed relative to body mass [Pmax/kg(W.kg-1)], and relative to the mass of two quadriceps muscles [Pmax/Quadr(W.kg-1Quadr)]. A negative relationship between Pmax/kg (Spearman's r = -0.56; P < 0.01), Pmax/Quadr (r = -0.53; P < 0.01) and Vopt (r = -0.45; P < 0.05) and age was found. Pmax/kg was positively associated with MHDEE (r = 0.51; P < 0.01) and sports activity (r = 0.58; P < 0.01), as were Pmax/Quadr and Vopt (r = 0.55; P < 0.01 and r = 0.54; P < 0.01, respectively). Pmax/kg, Pmax/Quadr and Vopt correlated positively with VO2max. The positive relationship between ergometer measurements and PA indices was similar to that between VO2max and PA. Pmax/kg was, moreover, closely related to Vopt (r = 0.77; P < 0.001). When a multiple stepwise regression analysis was used to select the variables influencing ergometer measurements, MHDEE contributed significantly to Pmax/kg variance, whereas sports activity contributed to Pmax/Quadr and Vopt variances. In conclusion, the data from this cross-sectional study suggest that in healthy elderly women habitual PA, and especially leisure time PA, alleviates the decline of the Pmax of the quadriceps muscles.