For older people exercise intensity is often determined based on heart rate (HR) or the percentage of maximal HR (%HRmax). This study evaluated oxygen uptake (O2) and HR during ergometry rowing (combined arm and leg; sitting exercise) and treadmill running (leg; upright exercise) for 15 older people [age, (mean +/- SD) 62 +/- 3 years]. The HR was lower during ergometry rowing than during treadmill running at a blood lactate concentration of 4 mmol l-1 (151 +/- 4 beat min-1 versus 160 +/- 5 beat min-1, P<0.05) and at a maximal effort (171 +/- 7 beat min-1 versus 177 +/- 7 beat min-1, P<0.05). This was the case although the O2 was higher during ergometry rowing than during treamill running both at a blood lactate concentration of 4 mmol l-1 (3.0 +/- 0.4 l min-1 versus 2.7 +/- 0.4 l min-1, P<0.05) and at a maximal effort (3.4 +/- 0.4 l min-1 versus 3.1 +/- 0.3 l min-1, P<0.05]. %HRmax and %HR reserve were lower during ergometry rowing than during treadmill running. The results suggest that, in prescription of rowing for older people, the relation between HR and O2 for rowing and the attenuated HR response to rowing should be taken into consideration.