Final answer:
VT2 represents the second ventilatory threshold during an incremental test protocol. At VT2, the body starts to rely more on anaerobic metabolism due to the accumulation of lactate. It is important for determining training intensities and assessing aerobic fitness.
Step-by-step explanation:
Vt2 represents the second ventilatory threshold during an incremental test protocol. It is the point at which an individual starts to rely more on anaerobic metabolism due to the accumulation of lactate in the bloodstream. At VT2, the body is no longer able to clear lactate efficiently, leading to fatigue and a decrease in exercise performance. This point is important for determining training intensities and assessing an individual's aerobic fitness.