Sports Engineering

, Volume 8, Issue 1, pp 27–38 | Cite as

A theoretical and experimental analysis of diver technique in underwater fin swimming

  • S. Samimy
  • J. C. MollendorfEmail author
  • D. R. Pendergast


This research was theoretical and experimental, with an objective of a better understanding of the physics of fin swimming. The theoretical work followed Lighthill’s slender body theory (1960). Video measurements were made on underwater fin swimmers swimming in an annular pool (58.6 m in circumference). This study considers only SCUBA divers. Five male swimmers swam at five speeds between 0.4 m/s-0.8 m/s. Skilled divers consumed less oxygen and had lower kick frequencies at each speed. The skilled divers adhered to the requirements of the theory, but not the unskilled. Specifically, the fin’s trailing edge (TE) lateral velocity was greater than the relative velocity of the water at the TE (requirement 1); which is the most forgiving. The second requirement is more stringent, and requires the TE lateral velocity and the relative velocity of the water at the TE to be of the same sign. Violating the first requirement sometimes causes a change in the instantaneous thrust’s direction. Violating the second requirement almost always produced instantaneous thrust in the opposite direction than the diver’s desired swimming direction. This study found that the Lighthill model can be used to describe diver fin swimming, which was optimised when the diver met the two requirements required for efficient thrust.


efficiency fin oxygen consumption skill swimming thrust 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Abbott, A.V., Brooks, A.N. & Wilson, D.G. (1995) Human powered watercrafts. In:Human Powered Vehicles (eds Abbott, V. & Wilson, D.R.), pp. 47–92. Human Kinetics, Champaign IL.Google Scholar
  2. Alexander, R. McN. (1983) Motion in fluids. In:Animal mechanics (ed Alexander, R.), pp 183–233. Blackwell Scientific Publications, Oxford.Google Scholar
  3. Bachrach, A.J. & Egstrom, G.H. (1987)Stress and performance in diving. Best Publishing Company, San Pedro, CA.Google Scholar
  4. Christianson, R.A., Weltman, G. & Egstrom, G.H. (1965) Thrust forces in underwater swimming.Human Factors,7, 561–568.Google Scholar
  5. di Prampero, P.E., Pendergast, D.R., Wilson, D. & Rennie, D.W. (1974) Energetics of swimming in man.Journal of Applied Physiology,37, 1–5.Google Scholar
  6. Hoerner, S.F. (1958)Fluid-dynamic drag. Published by author, Midland, NJ.Google Scholar
  7. Lighthill, M.J. (1960) Note on the swimming of slender fish.Journal of Fluid Mechanics,9, 305–317.CrossRefMathSciNetGoogle Scholar
  8. McMurray, R.G. (1977) Competitive efficiencies of conventional and super-swimfin designs.Human Factors,19, 495–501.Google Scholar
  9. Mollendorf, J.C., Felske, J.D., Samimy, S. & Pendergast, D.R. (2003) A fluid/solid model for predicting slender body deflection in a moving fluid.Journal of Applied Mechanics,70, 246–350.CrossRefGoogle Scholar
  10. Morrison, J.B. (1973) Oxygen uptake studies of divers when fin swimming with maximum effort at depths of 6–179 feet.Aerospace Medicine,44, 1120–1129.Google Scholar
  11. Pendergast, D.R., di Prampero, P.E., Craig, A.B., Wilson, D. & Rennie, W. (1977) Quantitative analysis of the front crawl in men and women.Journal of Applied Physiology,4, 475–479.Google Scholar
  12. Pendergast, D.R., Tedesco, M., Nawrocki, D.M. & Fisher, N.M. (1996) Energetics of underwater swimming with SCUBA.Medicine & Science in Sports & Exercise,28, 573–580.CrossRefGoogle Scholar
  13. Pendergast, D.R., Mollendorf J., Logue C. & Samimy S. (2003a) Evaluation of fins used in underwater swimming.Journal of Undersea & Hyperbaric Medicine,30, 57–73.Google Scholar
  14. Pendergast, D.R., Mollendorf J., Logue C. & Samimy S. (2003b) Underwater fin swimming in women with reference to fin selection.Journal of Undersea & Hyperbaric Medicine,30, 75–85.Google Scholar
  15. Samimy, S. (2002) Theoretical and experimental analysis of underwater fin swimming. Master’s Project, State University of New York at Buffalo, Buffalo, NY.Google Scholar
  16. Specht, H., Goff, L.G., Brubach, H.F. & Bartlett, R.G. (1957) Work efficiency and respiratory response of trained underwater swimmers using a modified self-contained underwater breathing apparatus.Journal of Applied Physiology,10, 376–383.Google Scholar
  17. Termin, B. & Pendergast, D.R. (2000) Training using the stroke frequency-velocity relationship to combine biomechanical and metabolic paradigms.Journal of Swimming Research,14, 9–17.Google Scholar
  18. Wu, TY-T. (1960) Swimming of a waving plate.Journal of Fluid Mechanics,10, 321–344.CrossRefGoogle Scholar
  19. Yamaguchi, H., Shidara, F., Naraki, N. & Mohri, M. (1995) Maximal sustained fin-kick thrust in underwater swimming.Underwater Hyperbaric Medicine,22, 241–248.Google Scholar
  20. Zamparo, P., Pendergast, D.R., Termin, B. & Minetti, A.E. (2002) How fins affect the economy and efficiency of human swimming.Journal of Experimental Biology,205, 2665–2676.Google Scholar

Copyright information

© isea 2005

Authors and Affiliations

  • S. Samimy
    • 3
  • J. C. Mollendorf
    • 1
    Email author
  • D. R. Pendergast
    • 2
  1. 1.Department of Mechanical & Aerospace EngineeringSchool of Engineering & Applied SciencesUSA
  2. 2.Department of Physiology & BiophysicsSchool of Medicine & Biomedical Sciences University at BuffaloBuffaloUS
  3. 3.Center for Research and Education in Special EnvironmentsBuffaloUS

Personalised recommendations