title: Metabolic responses to drafting during front crawl swimming.
abstract: We examined the metabolic responses to front crawl swimming when following directly behind (drafting) another swimmer. Seven trained male swimmers participated as subjects. VO2max (l.min-1) was measured during a progressive tethered swim test and was also estimated from a 20 s sample of expired air collected immediately after an all-out, 549 m (600 yard) swim. On different days, each subject performed two 549 m trials at 95% of his maximal swim velocity, one with drafting and one without drafting, using a counter-balanced design. Underwater pace lights were used to establish the predetermined swim velocity. Drafting significantly reduced post-exercise VO2 (2.85 +/- 0.63 vs 3.12 +/- 0.66 l.min-1), blood lactate (3.4 +/- 0.6 vs 5.0 +/- 0.5 mM), and rating of perceived exertion (11.7 +/- 0.4 vs 14.9 +/- 0.5) (P less than 0.05). A repeated measures ANOVA (condition X distance) also revealed significant reductions in HR during the 549 m swim (137.7 vs 146.8 beats.min-1) (P less than 0.05). The results indicate that drafting results in a decrease in energy expenditure for the range of speeds examined.
authors.affiliation: Department of Human Performance and Sport Studies, University of Tennessee, Knoxville 37996.
authors.forename: D R
authors.initials: DR
authors.lastname: Bassett
authors.forename: J
authors.initials: J
authors.lastname: Flohr
authors.forename: W J
authors.initials: WJ
authors.lastname: Duey
authors.forename: E T
authors.initials: ET
authors.lastname: Howley
authors.forename: R L
authors.initials: RL
authors.lastname: Pein
mesh_terms: D000328:Adult; D004734:Energy Metabolism / Q000502:physiology; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007773:Lactates / Q000097:blood; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D005082:Physical Exertion; D013550:Swimming
chemical_list: D007773:Lactates