2.4. Subjects’ Physical Profile and Exercise Workload Assessment
All subjects visited the laboratory to perform an incremental test on a bicycle ergometer (Ergoline 900, Cosmed, Albano Laziale (RM), Italy) in order to estimate both ventilatory thresholds (VT1 and VT2). During the test, gas exchange data were collected continuously using an automated breath-by-breath system (K5, Cosmed, Italy). The measuring instrument was calibrated before each test and the necessary environmental adjustments were made. The test protocol was composed of a rest phase 5 min long, where subjects remained seated on a bike without pedaling or other movements to assess basal parameters, a warm-up phase 3 min long, which consisted of pedaling with a power of 25 W, and an incremental phase, where pedaling was kept constant in a range of 70–80 rpm and the bike power increased by 5 W every 15 s. The incremental test was terminated (i) voluntarily by the subject, (ii) when pedaling cadence could not be kept firmly within range, or (iii) if in two successive load increments the VCOVT1 was determined using the criteria of an increase in the ventilatory equivalent for oxygen (VE/VOThe purpose of the preliminary session was to determine the individual workload to also collect each subject’s measurements needed in the experimental sessions, including saddle height and pedal position. Participants started cycling at 30 W and, after 3 min, workload was increased to the individual’s pre-assessed VT1 (aerobic workload) and maintained for 30 min. This workload had to have the characteristics of being predominantly aerobic and being able to be sustained by the subjects throughout the session. Subjects maintained pedal rates of 70–80 rpm throughout all the sessions (B and C). Participants wore individual outfits and were allowed to drink during the experimental session. Temperature and humidity of the laboratory were kept constant during all sessions.