Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT06057779 |
Other study ID # |
ONZ-2023-0238 |
Secondary ID |
|
Status |
Completed |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
September 25, 2023 |
Est. completion date |
January 10, 2024 |
Study information
Verified date |
June 2024 |
Source |
University Hospital, Ghent |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
Aim: To assess the influence of loading speed and intensity during eccentric heel drop
exercise on the immediate changes in Achilles tendon thickness and stiffness in healthy
controls.
Intervention: Three eccentric heel drop exercise protocols, different in loading speed and/or
loading intensity will be compared. Each participant will perform a single protocol per
session in a random sequence at 1-week intervals.
Participants: a total of 34 healthy athletes will be included.
Outcome measure: tendon thickness and stiffness will be measured at baseline and immediately
following intervention with ultrasound imaging (B-mode) and shear wave elastography,
respectively.
Discussion: the study will determine whether an eccentric exercise intervention involving a
low loading speed and high intensity could maximize the immediate reduction in thickness and
associated increase in stiffness of the Achilles tendon compared with interventions involving
a higher loading speed and lower intensity.
Description:
Mechanical loading of the Achilles tendon during isolated eccentric contractions induces
immediate changes in its structural properties. However, it is not known whether the loading
speed and intensity has any impact on these changes. Therefore, this study aims to
investigate the influence of loading speed and intensity during eccentric heel drop exercises
on the immediate changes in Achilles tendon thickness and stiffness in healthy controls.
Each participant will perform eccentric heel-drops on their dominant leg with and a fully
extended knee, and with additional 20% body weight (added via a weighted backpack).
Participants will stand with the forefoot of the tested limb on the edge of a step, with the
ankle maximally plantar flexed and with body weight centred on this limb. Eccentric loading
occurs when the participant lowers the heel to a predetermined angle and speed (depending on
the type of intensity and speed cfr infra). In order to return to baseline, the body mass
will therefore be shifted to the non-dominant leg to raise the body. Visual feedback
(monitor) will be in front of the subjects and the exercise parameters (velocity and ankle
angle) will be guided by software guidelines (Ultium Motion).
Three protocols will be compared that differ in execution speed (namely a fast protocol; 1
Hz: 1 second per repetition versus a slow protocol; 0.33 Hz: 3 seconds per repetition) and
loading intensity (namely heavy; exercise into maximal dorsiflexion versus light; exercise
into neutral ankle position).
Protocol 1 (=Heavy x Slow): subjects perform eccentric heel drops from a maximal
plantarflexion position to a maximal dorsiflexion position at a speed of 0.33 Hz, i.e. 3
seconds per movement cycle.
Protocol 2 (=Heavy x Fast): subjects perform eccentric heel drops from a maximal
plantarflexion position to a maximal dorsiflexion position at a speed of 3 Hz, i.e. 1 seconds
per movement cycle.
Protocol 3 (=Light x Slow): subjects perform eccentric heel drops from a maximal
plantarflexion position to a neutral ankle position at a speed of 0.33 Hz, i.e. 3 seconds per
movement cycle.
Participants will perform one exercise protocol per session, in a random order, and the
interval between each session is one week. Six sets will be performed per session, with one
minute of rest between each set. In order to ensure that the Achilles tendon's time under
tension is the same for each protocol (180 seconds), 30 repetitions will performed per set
for the fast protocol and 10 repetitions for the slow protocol. The approximate duration of
each intervention will be 15 minutes. Before and immediately after each protocol, the
structural properties of the Achilles tendon, 20 mm proximal to the calcaneal posterosuperior
border, will be assessed. These properties include tendon thickness (anteroposterior diameter
(mm), cross-sectional arae (mm2)), and tendon stiffness by shear wave elastography (m/s).