Annals of Biomedical Engineering

, Volume 28, Issue 4, pp 463–469 | Cite as

Fatigue-Related Loading Imbalance on the Shank in Running: A Possible Factor in Stress Fractures

  • J. Mizrahi
  • O. Verbitsky
  • E. Isakov


In previous reports we have shown that in long distance running the impact acceleration on the shank increases with progressing fatigue. The aim of the present study was to test whether, in parallel to this increase, an imbalance in the activities between the ankle plantar and dorsi flexor muscles develops. The tests were made on fourteen subjects during 30 min treadmill running above their anaerobic thresholds. Respiratory data were collected to determine the anaerobic threshold speed and to indicate the progressively developing metabolic fatigue. Surface electromyogram (EMG) was monitored to indicate the changing activity of the shank muscles. In the tibialis anterior the average integrated EMG (iEMG) and the mean power frequency (MPF) significantly decreased from the beginning to the end of running. In the gastrocnemius iEMG did not change, while MPF increased during the course of running. The impact acceleration, measured by means of an accelerometer attached to the tibial tuberosity, significantly increased during the course of running. It was concluded that, with developing fatigue, an imbalance in the contraction of the shank muscles develops in parallel to an increase in shank shock acceleration. The combination of these two changes may hamper the loading balance on the tibia since the bone becomes exposed to excessive bending stresses and to higher risk of stress injury. © 2000 Biomedical Engineering Society.

PAC00: 8719St, 0180+b, 8719Rr, 8719Nn, 8719Ff

Impact acceleration Tibial injury Bone load Tibialis anterior Gastrocnemius 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1_ Andersen, O. K., F. A. Sonnenborg, and L. Arendt-Nielsen. Modular organization of human leg withdrawal reflexes elicited by electrical stimulation of the foot sole. Muscle Nerve22:1520-1530, 1999.Google Scholar
  2. 2_ Baker, J., V. H. Frankel, and A. Burstein. Fatigue Fractures: Biomechanical Considerations. J. Bone Jt. Surg.54A:1345-1346, 1972.Google Scholar
  3. 3_ Beck, B. R.Tibial stress injuries. An aetiological review for the purposes of guiding management. Sports Med.26:265-279, 1998.Google Scholar
  4. 4_ Buczek, F. L., and P. R. Cavanagh. Stance phase knee and ankle kinematics and kinetics during level and downhill running. Med. Sci. Sports Exercise22:669-677, 1990.Google Scholar
  5. 5_ Burr, D. B. Bone, exercise and stress fracture. In: Exercise and sport sciences review, edited by J. O. Holloszy. Baltimore, MD: Williams and Wilkins, 1997, pp. 171–194.Google Scholar
  6. 6_ Burr, D. B., R. B. Martin, M. B. Schaffler, and E. L. Radin. Bone remodeling in response to in vivo fatigue microdamage. J. Biomech.18:189-200, 1985.Google Scholar
  7. 7_ Daffner, R. H.Anterior tibial striations. Am. J. Roentgenol.143:651-653, 1984.Google Scholar
  8. 8_ Dick, R. W., and P. R. Cavanagh. An explanation of the upward drift in oxygen uptake during prolonged sub-maximal downhill running. Med. Sci. Sports Exercise19:310-317, 1987.Google Scholar
  9. 9_ Dickinson, J. A., S. D. Cook, and T. M. Leinhardt. The measurement of shock waves following heel strike while running. J. Biomech.18:415-422, 1985.Google Scholar
  10. 10_ Edwards, R. H. Human muscle function and fatigue. Human muscle fatigue: physiological mechanisms. Pitman Medical, London (Ciba Foundation symposium 82) 1981, pp. 1–18.Google Scholar
  11. 11_ Elliot, B. C.and B. A. Blanksby. The synchronization of muscle activity and body segment movements during a running cycle. Med. Sci. Sports Exercise11:322-327, 1979.Google Scholar
  12. 12_ Fyhrie, D. P., C. Milgrom, S. J. Hoshaw, A. Simkin, S. Dar, D. Drumb, and D. B. Burr. Effect of fatiguing exercise on longitudinal bone strain as related to stress fracture in humans. Ann. Biomed. Eng.26:660-665, 1998.Google Scholar
  13. 13_ Herrmann, G., and H. Leibowitz. Mechanics of bone fracture. In: Fracture, Fracture of Nonmetals and Composites Vol. VII, edited by H. Leibowitz. New York: Academic, 1972, pp. 771–840.Google Scholar
  14. 14_ Hulkko, A., and S. Orava. Stress fractures in Athletes. Int. J. Sports Med.8:221-226, 1987.Google Scholar
  15. 15_ McLellan, T. M., and K. S. Cheung. A comparative evaluation of the individual anaerobic threshold and the critical power. Med. Sci. Sports Exercise24:543-550, 1992.Google Scholar
  16. 16_ Milgrom, C.The Israeli elite infantry recruit: a model for understanding the biomechanics of stress fractures. J. R. Coll. Surg. Edinburgh34:S18-S21, 1989.Google Scholar
  17. 17_ Mizrahi, J., and Z. Susak. In-Vivo elastic and damping response of the human leg to impact forces. ASME J. Biomech. Eng.104:63-66, 1982.Google Scholar
  18. 18_ Mizrahi, J., A. Voloshin, D. Russek, O. Verbitsky, and E. Isakov. The influence of fatigue on EMG and impact acceleration in running. Basic Appl. Myol.7:111-118, 1997.Google Scholar
  19. 19_ Mizrahi, J., O. Verbitsky, and E. Isakov. Shock accelerations and attenuation in downhill and level running. Clinical Biomech.15:15-20, 2000.Google Scholar
  20. 20_ Monteleone, G. P.Stress fractures in the athlete. Sports Med.26:423-432, 1995.Google Scholar
  21. 21_ Nordin, M., and V. Frankel. Biomechanics of bone. In: Basic biomechanics of the musculoskeletal system, edited by M. Nordin and V. Frankel. hiladelphia, PA: Lea and Febiger, 1989, pp. 3–29.Google Scholar
  22. 22_ Nummela, A., H. Rusko, and A. Mero. EMG activities and ground reaction forces during fatigued and nonfatigued sprinting. Med. Sci. Sports Exercise26:605-609, 1994.Google Scholar
  23. 23_ Portero, P., C. Vanhoutte, and F. Goubel. Surface electromyogram power spectrum changes in human leg muscles following 4 weeks of simulated microgravity. Eur. Phys. J.: Appl. Phys.73:340-345, 1996.Google Scholar
  24. 24_ Reber, L., J. Perry, and M. Pink. Muscular control of the ankle in running. Am. J. Sports Med.21:805-810, 1993.Google Scholar
  25. 25_ Reeder, M. T., B. H. Dick, J. K. Atkins, A. B. Probis, and J. M. Martinez. Stress fractures: current concepts of diagnosis and treatment. Sports Med.22:198-212, 1996.Google Scholar
  26. 26_ Sandor, B. I. Fundamentals of Cyclic Stress and Strain. Madison, WI: The University of Wisconsin Press, 1972.Google Scholar
  27. 27_ Schaffler, M. B., E. L. Radin, and D. B. Burr. Long-term fatigue behavior of compact bone at low strain magnitude and rate. Bone (N.Y.) 11: 321–326, 1990.Google Scholar
  28. 28_ Shorthen, M. R., and D. S. Winslow. Spectral analysis of impact shock during running. Int. J. Sport Biomech.6:288-304, 1992.Google Scholar
  29. 29_ Smeathers, J. E.Transient vibrations caused by heel strike. J. Eng. Med.203:181-186, 1989.Google Scholar
  30. 30_Standard for Medical and Dental Equipment, Underwriters Laboratories, 2nd. ed., UL 544, Northbrook, IL, 1982.Google Scholar
  31. 31_ Verbitsky, O., J. Mizrahi, A. Voloshin, Y. Treiger, and E. Isakov. Shock transmission and fatigue in human running. J. Appl. Biomech.14:300-311, 1998.Google Scholar
  32. 32_ Voloshin, A., J. Mizrahi, O. Verbitsky, and E. Isakov. Dynamic loading on the human musculoskeletal system—effect of fatigue. Clin. Biomech.13:515-520, 1998.Google Scholar
  33. 33_ Ward-Smith, A. J.The bioenergetics of optimal performances in middle-distance and long-distance track running. J. Biomech.32:461-465, 1999.Google Scholar
  34. 34_ Wasserman, K.Determinants and detection of anaerobic threshold and consequences of exercise above it. Circulation76(suppl. VI):VI-29, 1987.Google Scholar
  35. 35_ Yamada, H. Strength of biological materials. Baltimore: Williams and Wilkins. 1970.Google Scholar
  36. 36_ Yoshikawa, T., S. Mori, A. J. Santiesteban, T. C. Sun, E. Hafstad, J. Chen, and D. B. Burr. The effects of muscle fatigue on bone strain. J. Exp. Biol.188:217-233, 1994.Google Scholar
  37. 37_ Zajac, F. E., and M. E. Gordon. Determining muscle’s force and action in multi-articular movement. Exercise Sport Sci. Rev.117:187-230, 1987.Google Scholar

Copyright information

© Biomedical Engineering Society 2000

Authors and Affiliations

  • J. Mizrahi
    • 1
  • O. Verbitsky
    • 1
  • E. Isakov
    • 2
  1. 1.Department of Biomedical EngineeringTechnion—Israel Institute of TechnologyHaifaIsrael
  2. 2.Loewenstein Rehabilitation HospitalRaananaIsrael

Personalised recommendations