Age-related changes in cardio-respiratory responses and muscular performance following an Olympic triathlon in well-trained triathletes

The aim of the present study was to compare the maximal isometric torque and cardio-respiratory parameters in well-trained young and master triathletes prior to and following an Olympic distance triathlon. One day before and 24 h following the event, participants performed three maximum voluntary isometric knee extensions and flexions and an incremental running test on a treadmill to determine the maximal isometric torque, maximal oxygen uptake \( \left( {\dot{V}{\text{O}}_{2\max } } \right) \), speed at \( \dot{V}{\text{O}}_{2\max } \) (vVO₂max), speed at ventilatory thresholds (VT1 and VT2) and submaximal running economy. Prior to the event \( \dot{V}{\text{O}}_{2\max } \), vVO₂max, speed at ventilatory thresholds and running economy were significantly lower in master athletes, but maximal voluntary torque was similar between the groups. 24 h following the race, a similar significant decrease in \( \dot{V}{\text{O}}_{2\max } \) (−3.1% in masters, and −6.2% in young, p < 0.05), and vVO₂max (−9.5% in masters, and −5.6% in young, p < 0.05) was observed in both the groups. The speed at VT2 significantly decreased only in master athletes (−8.3%, p < 0.05), while no change was recorded in maximal voluntary torque or submaximal running economy following the event. The results indicate that for well-trained subjects, the overall relative exercise intensity during an Olympic distance triathlon and the fatigue 24 h following the event seem to be independent of age.