The use of the aerobic threshold as a basis for training.

Results from training studies, whose intensity is usually prescribed relative to VO2max, have shown wide variation in improvement among subjects with similar initial fitness levels. Since aerobic thresholds (AerT) of untrained males range from 35 to 65% VO2max, a large variation in stimulation and improvement may result in persons with different AerT values but similar fitness levels. The use of AerT as a training criterion was studied in 14 secondary males with an initial VO2max less than 47 ml.kg-1 min-1 and AerT values either greater than 55% or less than 45% VO2max. One group trained relative to VO2max (% MAX; N = 8) while the other trained relative to AerT (% AerT; N = 6) on the cycle ergometer 30-45 min.day-1, 3 times week-1 for 8 weeks. Intensity increased from 55 to 65% VO2max for the % MAX group and from 5 to 15% above individual AerT values for the % AerT group. Average intensity for the two groups was identical. Improvements in VO2max (ml.kg-1.min-1) from pre- to post-training were significantly greater for the % AerT group compared to the % MAX group (38.3 to 47.2 and 36.9 to 43.6, respectively). No difference in the variability of response to training was found between groups. There was a significant increase in absolute AerT values but no change was found when expressed relative to VO2max. It was concluded that the use of a training intensity relative to AerT values was as effective as % VO2max in enhancing cardiorespiratory fitness in initially untrained males.