FIGURE 3.

(A) MCAv was determined continuously by transcranial doppler ultrasound (TCD) and presented as change in MCAv from rest in each protocol for each participant. (B) P_ETCO₂ was determined by measurement of breath-by-breath respiratory gas exchange and ventilation. Data were averaged for 1 min during seated rest (Rest); over 30 s during the final minute of four 4 min high intensity (85% HR_max) interval bouts (HIIT; Ex 1 – 4); across the duration of four 30 s supramaximal (200% W_max) sprint intervals (SIT; Ex 1 – 4), and over a 30 s period, 15 s into the recovery following each bout in both interval protocols (Reco 1 – 4). Data are presented as mean ± SD (n = 24). Significance (analyzed by linear mixed model, p < 0.05) between time points is denoted by * for differences from resting values; ^€ for differences between interval (ex) and recovery (reco). Significant differences between protocols are denoted by ^Ω.