Sports Engineering

, Volume 12, Issue 4, pp 189–197 | Cite as

A dynamic model of the breast during exercise

Original Article

Abstract

The aim of this paper is to develop a method to determine the material characteristics of bras that could limit breast motion during exercise. A single participant ran on a treadmill at 10 km h−1 wearing either a sports bra, an everyday bra or no bra. The relative motion between the suprasternal notch and the breast was recorded using a passive marker system at 200 Hz and was modelled as forced damped-harmonic motion with a linear spring and damper, with the driving force provided by the suprasternal notch. The spring and damper values were found by matching the model to the experimental data. It was found that both the damping and stiffness values increased with the use of an everyday bra, and increased further still with the use of a sports bra. The stiffness parameter, however, was shown to be the most important criterion for minimisation of the breast motion. The model predicted that an increase in breast mass from 100 to 700 g (a 32A-cup to a 32F-cup) increased the vertical motion of the unsupported breast by around 70% when running and 30% when walking. This was reduced with an everyday bra and further reduced with the high stiffness sports bra. Although predictions were sensible, the model requires further verification with a cohort of participants.

Keywords

Breast displacement Forced harmonic motion Bra design 

References

  1. 1.
    Lawson L, Lorentzen D (1990) Selected sports bras: comparisons of comfort and support. Cloth Text Res J 8(4):55–60CrossRefGoogle Scholar
  2. 2.
    Mason B, Page KA, Fallon K (1999) An analysis of movement and discomfort of the female breast during exercise and the effects of breast support in three case studies. Aust J Sci Med Sport 2:134–144CrossRefGoogle Scholar
  3. 3.
    Wilson MC, Sellwood RA (1976) Therapeutic value of a supporting brassiere in mastodynia. Br Med J 2:90CrossRefGoogle Scholar
  4. 4.
    Hadi MSA (2000) Sports brassiere: is it a solution for mastalgia? Breast J 6:407–409CrossRefGoogle Scholar
  5. 5.
    The BRIDGE Study Group (1999) The presentation and management of breast symptoms in general practice in South Wales. Br J Gen Pract 49(447):811–812Google Scholar
  6. 6.
    Page K, Steele J (1999) Breast motion and sports brassiere design, implications for future research. Sports Med 27:205–211CrossRefGoogle Scholar
  7. 7.
    McGhee DE, Steele J (2006) How do respiratory state and measurement method affect bra size calculations? Br J Sports Med 40:970–975CrossRefGoogle Scholar
  8. 8.
    Turner AJ, Dujon DG (2005) Predicting cup size after reduction mammoplasty. Br J Plast Surg 58:290–298CrossRefGoogle Scholar
  9. 9.
    Scurr J, White J, Hedger W (2009) Breast displacement in three dimensions during the walking and running gait cycles. J Appl Biomech 25:322–329Google Scholar
  10. 10.
    Foley J, van Dam A, Feiner SK, Hughes JF (1995) Computer graphics principles and practice in C, 2nd edn. Addison-Wesley, Boston, pp 213–236Google Scholar
  11. 11.
    Diedrich FJ, Warren WH Jr (1995) Why change gaits? Dynamics of the walk-run transition. J Exp Psychol Hum Percept Perform 28(1):183–202Google Scholar
  12. 12.
    Fung YC (1993) Mechanical properties of living tissues, 2nd edn. Springer, New York, p 568Google Scholar
  13. 13.
    Silver FH, Freeman JW, DeVore D (2001) Viscoelastic properties of human skin and processed dermis. Skin Res Technol 7:18–23CrossRefGoogle Scholar

Copyright information

© International Sports Engineering Association 2010

Authors and Affiliations

  1. 1.Centre for Sport and Exercise ScienceSheffield Hallam UniversitySheffieldUK
  2. 2.Department of Sport and Exercise ScienceUniversity of PortsmouthPortsmouthUK

Personalised recommendations