Abstract

Seven men and four women (age 63 +/- 2 yr, mean +/- SD, range 61-67 yr) participated in a 12-mo endurance training program to determine the effects of low -intensity (LI) and high-intensity (HI) training on the blood lactate response to submaximal exercise in older individuals. Maximal oxygen uptake (VO2max), blood lactate, 02 uptake (VO2), heart rate (HR), ventilation (VE), and respiratory exchange ratio (R) during three submaximal exercise bouts (65-90 VO2 max) were determined before training, after 6 mo of LI training, and after an additional 6 mo of HI training. VO2 max (ml/kg/min) was increased 12 after LI training, while HI training induced a further increase of 18. Lactate, HR, VE, and R were significantly lower at the same absolute work rates after LI training, while HI training induced further but smaller reductions in these parameters. In general, at the same relative work rates (i.e., of VO2 max) after training, lactate was lower or unchanged, HR and R were unchanged, and VO2 and VE were higher. These findings indicate that LI training in older individuals results in adaptations in the response to submaximal exercise that are similar to those observed in younger populations and that additional higher intensity training results in further but less-marked changes. Verf.-Referat