Oxygen Consumption When Kicking With Open Water Lifeguard Fins

INTRODUCTION: Open water lifeguards have utilized fins for decades to perform rescues, yet no data exists on the impact of differing fin designs on the metabolic cost when kicking. Purpose: Therefore, the purpose of this study was to determine the metabolic cost of kicking with three pairs of lifeguard fins and one pair of swim fins. We hypothesized that lifeguard fins would be more metabolically efficient compared to swim fins. METHODS: Thirty-one men and women (22 men and 9 women; 24 ± 6 years old) with 17 ± 7 years swimming experience and 3 ± 2 years lifeguard experience participated in this study. Participants performed a maximal graded exercise test to exhaustion in an Endless Pool with a kickboard while wearing the swim fins (Arena) that began at 0.5 m/s and increased by 0.1 m/s every min until volitional fatigue. Subsequently, participants performed four 5-min submaximal kicking trials wearing each of the four fins (Arena, DaFin, Viper, and Duck Feet) in random order at a pace equivalent to 80% of the maximum speed achieved on the graded exercise test. RESULTS: The 2-D surface area of all fin sizes were 302 ± 135 cm2 for Arena, 326 ± 178 cm2 for DaFin, 369 ± 190 cm2, and 371 ± 160 cm2 for Duck Feet. The average water current for the trials was 0.93 ± 0.17 m/s, which is equivalent to 1:48 ± 0:10 per 100 m pace. The mean VO2 for the Arena, DaFin, Viper, and Duck Feet trials were 28.6 ± 5.3, 24.9 ± 5.1, 26.8 ± 5.2, and 24.4 ± 5.5 ml kg -1 min-1, respectively. Two lifeguard fins (DaFin and Duck Feet) had significantly lower VO2 compared to the swim fins (p = 0.03 and p = 0.01, respectively), but there were no significant differences among lifeguard fins. CONCLUSION: Results suggest fin design affects metabolic cost of kicking when comparing lifeguard fins to swim fins. Therefore, it is likely that lifeguards’ fin choice should be based on other criteria such as comfort given that their metabolic cost is similar. T32GM146604