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The mechanical efficiency of locomotion in men and women with special emphasis on stretch-shortening cycle exercises

  • Ossi Aura
  • Paavo V. Komi
Article

Summary

The mechanical efficiency of the leg extensor musculature of men and women was examined with a special “sledge ergometer”. The subjects (ten males and ten females) performed (a) pure positive work, (b) pure negative work and (c) a combination of negative and positive work (strech-shortening cycle). The mechanical efficiency of pure positive work was on average 19.8±1.2% for female subjects and 17.4±1.2% for male subjects (t=4.12, P<0.001), although the work intensity was equal in both groups. The mechanical efficiency of pure negative work was slightly lower in women than in men (59.3±14.4% vs 75.6±29.3%). The mechanical efficiency of positive work (η+) in a stretch-shortening cycle exercise was 38.1±6.8% in men and 35.5±6.9% in women. The utilization of prestretch was better for female subjects at low prestretch levels, whereas males showed greater potentiation of elastic energy at higher prestretch levels. Regarding absolute Wel (work due to elasticity) values, male subjects showed greater (P<0.001) values than females (189±44 J vs 115±36 J, respectively). Fundamental differences in neuromuscular functions in men and women might cause the differences in the results obtained.

Key words

Mechanical efficiency Positive work Negative work Stretch-shortening cycle 

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References

  1. Asmussen E, Bonde-Petersen F (1974) Apparent efficiency and storage of elastic energy in human muscles during exercise. Acta Physiol Scand 92:537–545Google Scholar
  2. åstrand P-O (1952) Experimental studies of physical working capacity in relation to sex and age. Munksgaard, CopenhagenGoogle Scholar
  3. åstrand L, åstrand P-O, HallbÄck I, Kilbom å (1973) Reduction in maximal oxygen uptake with age. J Appl Physiol 43:649–654Google Scholar
  4. Aura O, Komi PV (1986a) The mechanical efficiency of pure positive and pure negative work with special reference to the work intensity. Int J Sports Med (in press)Google Scholar
  5. Aura O, Komi PV (1986b) Effects of prestretch intensity on the mechanical efficiency of positive work and on elastic behaviour of skeletal muscle in stretch-shortening cycle exercise. Int J Sports Med (in press)Google Scholar
  6. Bosco C, Komi PV, Sinkkonen K (1980) Mechanical power, net efficiency and muscle structure in male and female middle-distance runners. Scand J Sports Sci 2:47–51Google Scholar
  7. Bosco C, Ito A, Komi PV, Luhtanen P, Rahkila P, Rusko H, Viitasalo JT (1982) Neuromuscular function and mechanical efficiency of human leg extensor muscles during jumping exercise. Acta Physiol Scand 114:543–550Google Scholar
  8. Cavagna GA, Kaneko M (1977) Mechanical work and efficiency in level walking and running. J Physiol 268:467–481Google Scholar
  9. Cavagna GA, Saibene FP, Margaria R (1965) Effect of negative work on the amount of positive work performed by an isolated muscle. J Appl Physiol 20:157–158Google Scholar
  10. Davies CMT, Barnes C (1972) Negative (eccentric) work. II Physiological responses to walking uphill and downhill on a motor-driven treadmill. Ergonomics 15:121–131Google Scholar
  11. Dickinson S (1929) The efficiency of bicycle-pedalling as affected by speed and load. J Physiol 67:242–255Google Scholar
  12. Gaesser GA, Brooks GA (1975) Muscular efficiency during steady-rate exercise: effects of speed and work rate. J Appl Physiol 38:1132–1139Google Scholar
  13. Ito A, Komi PV, Sjödin B, Bosco C, Karlsson J (1983) Mechanical efficiency of positive work in running of different speeds. Med Sci Sports 15:299–308Google Scholar
  14. Julian FJ, Morgan DL (1979) The effect on tension of nonuniform distribution of length changes applied to frog muscle fibres. J Physiol [Lond] 293:379–392Google Scholar
  15. Kamon E (1970) Negative and positive work in climbing a ladder-mill. J Appl Physiol 29:1–5Google Scholar
  16. Kaneko M, Komi PV, Aura O (1984) Mechanical efficiency of concentric and eccentric exercises performed with medium to fast contraction rates. Scand J Sports Sci 6:15–20Google Scholar
  17. Komi PV (1981) Fundamental performance characteristics in females and males. Med Sport 14:102–108Google Scholar
  18. Komi PV, Bosco C (1978) Utilization of stored elastic energy in leg extensor muscles by men and women. Med Sci Sports 10:261–265Google Scholar
  19. Komi PV, Karlsson J (1978) Skeletal muscle fibre types, enzyme activities and physical performance in young males and females. Acta Physiol Scand 103:210–218Google Scholar
  20. Komi PV, Rusko H, Vos J, Vihko V (1977) Anaerobic capacity in athletes. Acta Physiol Scand 100:107–114Google Scholar
  21. Margaria R (1968) Positive and negative work performance and their efficiencies in human locomotion. Int Z Angew Physiol Einschl Arbeitsphysiol 25:339–351Google Scholar
  22. McDonald I (1961) Statistical studies of recorded energy expenditure of man. II: Expenditure on walking related to weight, sex, age and gradient. Nutr Abstr Rev 31:739–762Google Scholar
  23. Pahud P, Ravussin E, Acheson KJ, Jequier E (1980) Energy expenditure during oxygen deficit of submaximal concentric and eccentric exercise. J Appl Physiol 49:16–21Google Scholar
  24. Pandolf KB, Kamon E, Noble BJ (1978) Perceived exertion and physiological responses during negative and positive work in climbing a laddermill. J Sports Med 18:227–236Google Scholar
  25. Pugh LGCE (1971) The influence of wind resistance in running and walking and the mechanical efficiency of work against horizontal and vertical forces. J Physiol 213:255–276Google Scholar
  26. Thys H, Faraggiani T, Margaria R (1972) Utilization of muscle elasticity in exercise. J Appl Physiol 32:491–494Google Scholar
  27. Winter DA (1979) A new definition of mechanical work done in human movement. J Appl Physiol 46:79–83Google Scholar

Copyright information

© Springer-Verlag 1986

Authors and Affiliations

  • Ossi Aura
    • 1
  • Paavo V. Komi
    • 1
  1. 1.Department of Biology of Physical ActivityUniversity of JyvÄskylÄJyvÄskylÄFinland

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