The study purpose is to determine if aerobic training affects aerobic capacity, as well as anaerobic threshold, minute ventilation (VE), ratio of expired carbon dioxide to oxygen utilization (VCO 2 , VO 2 ). The research methods used were: bibliographical study, observation, Bruce protocol with the computerized assessment of expired gases. Three recreational athletes were tested for basal VO 2 max and data were used to determine their first (VT1) and second (VT 2 ) ventilatory thresholds, VE (L/min), VCO 2 /VO 2 (%). The intervention consisted in a 2-month period of aerobic training focused on building volume at 65% VO 2 . Exercise volume was controlled across the 2-month period by varying duration and frequency. Intensity during exercise was controlled by monitoring the subjects' heart rate (HR) to stay within targeted HR zones. In the first 4 weeks, it was used a volume of around 300km (65% VO 2 max), and for the second 4 weeks, the volume increased to around 380km (65% VO 2 max). After two months of training VO 2 max, VT1 and VT2, we found significant improvements in both ventilatory thresholds, and also in VE, VCO 2 and VO 2 . VO 2 max did not improve significantly, but there were improvements in all three subjects in their VT1, VT2, VCO 2 /VO 2 and VE. When exercise volume is controlled and individualized based on VT, adaptation to training improves both VT1 and VT2, the subject performing no anaerobic activity over a period of 2 months.