Table 1.

Muscle metabolic responses in Leg_1CON, Leg_1PL, Leg_1ACT, Leg_2CON, Leg_2PL-CONTRA, and Leg_2ACT-CONTRA conditions

	Leg1CON	Leg1PL	Leg1ACT	Leg2CON	Leg2PL-CONTRA	Leg2ACT-CONTRA
[PCr]
Baseline, %	100 (0)	100 (0)	100 (0)	100 (0)	92 (5)*	93 (4)*
120 s, %	70 (8)	70 (8)	71 (7)	71 (8)	62 (9)*	63 (7)*
End exercise, %	42 (9)	41 (9)	41 (8)	44 (8)	45 (7)	44 (8)
Rate of change, mmol/s	−0.06 (0.01)	−0.06 (0.03)	−0.06 (0.02)	−0.05 (0.03)	−0.06 (0.04)	−0.06 (0.03)
[Pi]
Baseline, %	100 (0)	100 (0)	100 (0)	100 (0)	125 (24)*	126 (23)
120 s, %	310 (66)	313 (71)	306 (62)	312 (66)	316 (70)	318 (64)
End exercise, %	590 (149)	590 (137)	594 (156)	588 (177)	459 (110)*	460 (109)*
Rate of change, mmol/s	0.05 (0.02)	0.05 (0.02)	0.05 (0.02)	0.05 (0.02)	0.05 (0.02)	0.05 (0.02)
[ADP]
Baseline, %	100 (0)	100 (0)	100 (0)	100 (0)	200 (78)*	201 (77)*
120 s, %	404 (161)	415 (183)	400 (148)	412 (170)	538 (176)	516 (154)*
End-exercise, %	1,028 (386)	1,036 (421)	1,046 (409)	1,024 (401)	980 (316)	978 (312)
Rate of change, µmol/s	0.15 (0.08)	0.15 (0.09)	0.14 (0.07)	0.15 (0.09)	0.17 (0.10)	0.15 (0.09)
pH
Baseline	7.04 (0.01)	7.03 (0.02)	7.05 (0.04)	7.04 (0.03)	7.04 (0.03)	7.05 (0.02)
120 s	6.96 (0.09)	6.94 (0.07)	6.92 (0.08)	6.95 (0.08)	6.93 (0.10)	6.94 (0.08)
End-exercise	6.77 (0.18)	6.76 (0.15)	6.76 (0.16)	6.83 (0.15)	6.83 (0.20)	6.80 (0.15)

Values are means (SD) of 14 male subjects who performed single-leg severe-intensity knee-extensor exercise to task failure on the left (Leg₁) and right (Leg₂) legs without prior contralateral fatigue and on Leg₂ immediately following Leg₁ (Leg_2-CONTRA). PL, placebo; ACT, acetaminophen; [PCr], phosphocreatine concentration; [Pi], Pi concentration; [ADP], ADP concentration.

^*P < 0.05 vs. Leg_2CON.