Fig. 3

Δ%\({\dot{V}}_{{\text{O}}_{\text{2peak}}}\)-adjusted Δ pupil diameter, Δ \({\dot{V}}_{\text{E}},\) and Δ HR for each intensity interval. R, rest; VL, very-light; L, light; M, moderate; V, vigorous; NM, near maximal/maximal; \({\dot{V}}_{{\text{O}}_{\text{2peak}}}\), peak oxygen uptake; HR, heart rate; \({\dot{V}}_{E}\), minute ventilation; ^aP < 0.05 greater than R-VL; ^bP < 0.05 greater than VL-L; ^cP < 0.05 greater than L-M; ^dP < 0.05 greater than M-V. Data are presented as mean ± SE