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Calculation of the external work done during walking in very young children

Benedicte Schepens1, Christine Detrembleur

  • 1Université catholique de Louvain, Louvain-la-Neuve, Belgium. benedicte.schepens@uclouvain.be

European Journal of Applied Physiology
|July 28, 2009
PubMed

Insights

Young children

Area of Science:

  • Biomechanics
  • Human locomotion
  • Developmental pediatrics

Background:

  • Muscles perform positive work during walking to compensate for energy loss.
  • Young children exhibit immature and irregular walking patterns.
  • The impact of irregular gait on muscular external work in children is not well understood.

Purpose of the Study:

  • To measure muscular external work in 1-year-old, 4-year-old children, and adults during walking.
  • To evaluate the approximation of using only positive external work to represent total external work.
  • To analyze the effect of gait irregularity on work measurements.

Main Methods:

  • Utilized force platforms and the Cavagna method (J Appl Physiol 39:174-179, 1975).
  • Assessed muscular external work during walking across different age groups.
  • Investigated gait variability and its influence on work calculations.

Main Results:

  • Confirmed young children's inability to maintain constant walking speed over multiple steps.
  • Demonstrated that work for center of mass maintenance in the transversal plane is minimal (<10% of positive work).
  • Highlighted that gait irregularity in young subjects does not significantly skew positive external work measurements.

Conclusions:

  • External work measurement is a valuable indicator of gait mechanics.
  • Interpreting external work data requires careful consideration of gait regularity, especially in young, developing populations.
  • The positive external work approximation remains a reasonable metric even with irregular gait patterns in children.

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