Oxygen uptake and cardiorespiratory parameters were measured during submaximal and maximal work in flume swimming, bicycling and treadmill running, in order to compare physiological responses of swimmers to those three types of exercise. Subjects were divided into three groups according to the level of swimming training, i, e., 5 less trained water polo players (group A), 5 male well trained college swimmers (group B) and 14 male elite swimmers (group C) .
V_2max during swimming in group A (3.11 1/min) was 5% lower than during bicy cling, while those in group B (3.63 1/min) and C (4.12 1/min) were 9% and 11% higher, respectively. Comparing with running, Vo_2max during swimming was 19% lower in group A, and was about the same in group B.
V_E and V_E/ Vo₂ were lower during submaximal and maximal swimming compared with bicyling and running, in all groups except the maximal work of group C. Lower V_E during swimming resulted from lower f as well as lower V_T. The difference in V_A between during swimming and during running, bicycling was small compared with that in V_E.
Q during swimming increased almost linearly with Vo₂ in all groups. At a given Vo_2submax, Q was about the same in three types of exercise. Q during maximal swimming in group A (19.7 1/min) and B (21.3 1/min) were similar compared with bicycling, but were 16% and 11% lower compared with running, respectively. Q_max during swimming in group C (23.8 1/min) was 5% higher compared with bicycling.
HR increased almost linealy with Vo₂ in all exercise. At a given Vo_2submax, HR was 4-5 beats/min less during running than during bicycling, and was 10-20 beats/min less during swimming than during those two types of exercise. HR_max was lower during swimming compared with bicycling or running in all groups. A similar Q at submaximal work during three types of exercise resulted from higher SV and lower HR in swimming.