UHM 2003, Vol. 1, No. 30 - Underwater fin swimming in women Underwater fin swimming in women with reference to fin selection D.R. PENDERGAST 1,2 , J. MOLLENDORF 1,3 , C. LOGUE 1,2 , and S. SAMIMY 1,3 Center for Research and Education in Special Environments 1 Departments of Physiology and Biophysics 2 and Mechanical and Aerospace Engineering 3 Schools of Engineering and Medicine and Biomedical Sciences University at Buffalo, Buffalo, NY 14214 Pendergast D, Mollendorf J, Logue C, Samimy S, Underwater fin swimming in women with reference to fin selection. Undersea Hyperb Med 2003; 30(1): 72-82 - Underwater swimmers use fins, which provide thrust to overcome drag and propel the diver. The type of fin used has been shown to affect diver performance, however data are lacking for women. The oxygen consumption (VdotO 2 ) of swimming as a function of speed, velocity as a function of kick frequency, maximal speed (v), maximal VdotO 2 and the maximal thrust were determined for 8 female divers swimming at 1.25 m depth in a 60 m annular pool. VdotO 2 increased as a function of v as; 0.52 + -0.485 V + 2.85 V 2 (r 2 = 0.996) and 0.12 + 1.52 V +1.275 V 2 (r 2 = 0.999) for high (5 fins) and low (3 fins) groupings, respectively. Splits, vents and flanges did not significantly affect VdotO2. Kick frequency increased linearly with v, with unique slopes for each fin. Maximal VdotO 2 was not affect by fin type (1.46 ± 0.05 l/min). Velocities that could be stained aerobically were 0.60 ± 0.02 m/sec on average, with the most flexible fin higher (0.71 m/sec). Maximal v averaged 0.87 ± 0.03 m/sec, with the most rigid fin lower (0.77 m/sec). Maximal thrust was not affected by fin and averaged 104 ± 9 N. It can be concluded that female divers preferred the most flexible fins, which were also the most economical. This is most likely due to low leg power, which could also explain the absence of differences in maximal thrust and velocity. SCUBA diving, oxygen consumption, kick frequency, thrust, fins INTRODUCTION Sport diving has become a popular recreation, and is becoming more popular among women. An important component of diving is underwater swimming using fins for propulsion. As fins come in a wide variety of shapes, materials and designs and all of which are reported to improve the diver’s performance, fin selection can impact diving performance and success. Fin selection is often subjective, but performance is dependent upon the diver having the leg power to kick the fin and the metabolism to sustain muscle contractions over the period of the swim. To swim at a given speed the diver must provide a thrust per kick, which overcomes drag, and propels the body forward. The total thrust is met by the thrust per kick times the frequency of kicking, thus there is a relationship between the distance the body goes per kick and the kick frequency as a function of velocity. To swim with fins, women would have to be able to generate a force with a flutter kick to propel the fin and generate sufficient thrust to over come Copyright © 2003 Undersea and Hyperbaric Medical Society, Inc. 72 http://rubicon-foundation.org