Article

A force-driven harmonic oscillator (FDHO) model reveals the elastic
property of general muscular activity during walking.
This study aimed
to investigate whether children with Down syndrome (DS) have a lower K/G ratio, a
primary variable derived from the FDHO model, compared with children with typical
development during overground and treadmill walking and whether children with DS
can adapt the K/G ratio to walking speeds, external ankle load, and a treadmill
setting. DESIGN: A cross-sectional study design was used that included 26
children with and without DS, aged 7 to 10 years, for overground walking and 20
of them for treadmill walking in a laboratory setting. METHODS: During overground
walking, participants walked at 2 speeds: normal and fastest speed. During
treadmill walking, participants walked at 75% and 100% of their preferred
overground speed. Two load conditions were manipulated for both overground and
treadmill walking: no load and an ankle load that was equal to 2% of body mass on
each side. RESULTS: Children with DS showed a K/G ratio similar to that of their
healthy peers and increased this ratio with walking speed regardless of ankle
load during overground walking. Children with DS produced a lower K/G ratio at
the fast speed of treadmill walking without ankle load, but ankle load helped
them produce a K/G ratio similar to that of their healthy peers. LIMITATIONS: The
FDHO model cannot specify what muscles are used or how muscles are coordinated
for a given motor task. CONCLUSIONS: Children with DS show elastic property of
general muscular activity similar to their healthy peers during overground
walking. External ankle load helps children with DS increase general muscular
activity and match their healthy peers while walking fast on a treadmill.
CI - (c) 2015 American Physical Therapy Association.

Langue : ANGLAIS