Abstract

The anaerobic threshold (AT) was determined noninvasively during incremental exercise on a bicycle ergometer in two groups (N=22, N2=16) of healthy, untrained middle-aged men (mean age, 31.5+/-4.8, and 51.8 +/-5.4 years; maximal rate of oxygen consumption (VO2max) was 43.3+/-7.9, and 34.4+/-8.0 ml/kg/min) using two testing methods simultaneously; ventilatory threshold and heart rate response (the modified Conconi test). The value of selected functional parameters at AT determined by either method showed no significant difference between the two determinations either in absolute or relative terms. A high correlation was found between the value of the functional parameters at the AT estimated by the two methods (p<0.005 in all cases). The two methods of AT determination are interchangeable and may be used under the following conditions: The initial exercise intensity is between 40 and 60 of VO2max; the duration of each exercise increment ranges from 30 to 90 seconds; the increments cause a heart rate increase of 4 to 6 beats/min; the total number of exercise increments ranges from 5 to 12. AT determination from heart rate response may also be performed in older subjects (with about a 93 success rate) under laboratory and field conditions. Verf.-Referat