Abstract

The effects of prolonged endurance training on maximal 02 uptake capacity (VO2 max) and its determinants were studied in 11 older individuals (63 +/- 2 yr). The subjects were evaluated before training, after 6 mo of low-intensity (LI) training, and after an additional 6 mo of higher intensity (HI) training. VO2 max was 25.4 +/- 4.6 ml/kg/min before training, 28.2 +/- 5.2 ml/kg/min after LI training, and 32.9 +/- 7.6 ml/kg/min after HI training, with an overall incraese of 30. The increase in VO2 max in response to training appeared to be mediated primarily through an increase in maximal arteriovenous O2 difference, with little augmentation of maximal cardiac output (Q). At the same absolute work rates, stroke volume was higher; heart rate (HR), blood pressure (BP), and systemic vascular resistance were lower; and Q and arteriovenous O2 difference were unchanged after training. At the same relative work rates, arteriovenous O2 difference was higher; BP and systemic vascular resistance were lower; and HR, Q, and stroke volume did not change significantly. These findings show that older individulas can adapt to prolonged endurance training with a large increase in aerobic power. Verf.-Referat