The aim of this study was to investigate the effects of swimming suit with different materials and functions on active drag and oxygen uptake (VO₂) during swimming. The subjects were 8 well-trained male college swimmers (age: 21 ± 1 yrs). For this experiment, drag-swimming velocity relationship and VO₂ during submaximal swimming were determined using conventional swimming suit (short type) and 3 new types of swimming suit (long type) developed in 2008. The active drag force was directly measured during arm stroke swimming using a system of underwater push-off pads instrumented with a force transducer (MAD system). There were no significant differences in VO₂ at the water flow rate of 1.2 m･s⁻¹ among the conditions. The estimated drag values at 1.2, 1.6, and 2.0 m.s⁻¹ were not statistically significant among the suits, although drag reduction by 1-6 N (3-6%) was observed for new types of suits when compared to a conventional suit (but non-significant). Furthermore, when 100m to 400m race times were estimated based on the drag and metabolic power of each subject, a reduction of 1 to 4 s in race times would be expected by wearing new types of suit. These results suggest that on a group level, there were statistically non-significant reduction of drag and energy cost during swimming when compared to those of conventional suit but that some small reduction of drag and improvement of performance might be brought.

DESCENTE SPORTS SCIENCE Vol.31/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE