Table 3.

Effect of exercise intensity on kinetic parameters of the VO₂ on and off-kinetics responses to square-wave exercise of moderate (M), heavy (H) and very heavy (VH) intensity by race.

	African Americans			Caucasians
On	M	H	VH	M	H	VH
A1 (L min−1)	0.36±0.12	0.67±0.15a	1.01±0.17a	0.69±0.19b	0.97±0.15a,b	1.27±0.16a
A2 (L min−1)		0.12±0.09	0.29±0.32		0.17±0.08	0.35±0.2
δ1 (s)	19.1±5.2	16.4±2.5	15.3±1.7	17.2±3.8	15.2±2.2	15.0±3.7
δ2 (s)		174.6±35.8	107.0± 18.3		148.5±36.8	123.2±25.4
τ1 (s)	39.4±12.5	47.0±10.8	44.3±10	38.8±15	41.0±12	43.2±15
τ2 (s)		288.6±63	219.3±90		276.5±81	215.0±36
G1 (mL min−1 W−1)	9.3±0.7	10.3±1.9	9.9±1.5	ll±0.9b	10.8±0.7	10.1±1.4
GTOT (mL min−1 W−1)		12.3±1.85c	12.4±3.1c		12.7±1.1c	12.9±1.9c
OFF	M	H	VH	M	H	VH
A1 (L min−1)	0.39±0.14	0.70±0.13a	1.03±0.26a	0.68±0.18b	1.00±0.17a,b	1.21±0.16a
A2 (L min−1)		0.08±0.03	0.16±0.1		0.09±0.05	0.15±0.08
δ1 (s)	14.0±1.3d	13.4±1.8	15.4±2.2	14.1±1.5	15.7±1.2	16.2±2.2
δ2 (s)		142.7±74	151.6±26		142.7±44.7	149.5±31.6
τ1 (s)	52.7±10.1d	45.9±6.2	50.7±10	40.7±4.4	40.2±3.4	42.3±7.25
τ2 (s)		258.9±120	242.6±93		214.8±132.8	222.7±64.1
G1 (mL min−1 W−1)	10.1±0.9	10.9±1.3	10.0±2.5	10.8±0.7	11.2±1.2	9.6±1
G1 (mL min−1 W−1)		12.3±1.5c	11.5±3.2c		12.2±lc	10.8±1.6c

^aP<0.05, significantly different from other exercise intensities within group.

^bP<0.05, significant influence of race (considering the specific intensity domain).

^cP<0.05, greater than their respective fundamental gains.

^dP<0.05, significantly different from VO₂ on response (considering the specific intensity domain).