_max, HR and [L⁻] attained at the limit of tolerance during the control and maximal HIIT protocols.

Values are means ± SD. _max (maximal rate of pulmonary oxygen uptake); HR (heart rate) and [L⁻] (Lactate concentration) measured at the limit of tolerance during the constant-speed tests used to characterize the Speed-tolerable duration (S-t_LIM) relationship (Control) and ON bouts 1, 2, 3 and 4 of the maximal HIIT protocol.

Significantly lower [L⁻] than that achieved in Bout 2.