Sixty-seven male and 68 female overweight (body mass index (BMI) = 25-29.9 kg.m) and obese (BMI>or = 30 kg x m) participants undertook a graded treadmill test to volitional exhaustion (phase 1) followed by a verification test (phase 2) to determine the proportion who could achieve a plateau in (.)VO2 and other "maximal" markers (RER, lactate, HR, RPE).