DRAFTING BEHIND ANOTHER SWIMMER IMPROVES PERFORMANCE AND CONSERVES ENERGY
Chatard, J.C., Chollet, D., & Millet, G. (1998). Performance and drag during drafting swimming in highly trained triathletes. Medicine and Science in Sports and Exercise, 30(8), 1276-1280.
The influence of drafting was studied on the swimming performance, metabolic response, and passive drag of triathletes (N = 8).
Performance in drafting position was measured directly behind another swimmer during a 400-m swim and compared with a nondrafting position. Metabolic responses recorded were VO2, blood lactate, stroke rate, stroke length, and rating of perceived exertion. Drag was measured by passive towing.
In drafting position, Ss swam on average 3.2% faster over the 400-m swim than in nondrafting position (4 min, 47.69 +/- 10.35 s vs 4 min, 57.25 +/- 7.24 s; p < 0.01). Blood lactate and stroke rate were significantly lower (9.6 mM vs 10.8 mM; 39.9 cycle/min vs 41.3 cycle/min p < 0.02) and stroke length longer (2.10 m/cycle vs 1.97 m/cycle, p < 0.01) than in a nondrafting position. VO2 and rating of perceived exertion were not statistically different. Passive drag was lower in drafting than in nondrafting position (p < 0.01). However, the gain in drag decreased with increase in velocity (from 26% at 1.1 m/s to 13% at 1.7 m/s). In drafting performance gain was related to 400-m time (r = 0.80, p < 0.01) and to the skinfold thickness (r = 0.94, p < 0.01), with faster and leaner swimmers having greater gains of performance.
Swimming behind another swimmer in a race is advantageous for triathletes.
Implication. Performance improvements and energy conservation are facilitated by drafting behind another swimmer.
Return to Table of Contents for Hydrodynamics of Swimming.