Effects of Long-Distance and Short-Distance Running Loads on Achilles Tendon Structure and Recovery Process: An Ultrasound Imaging Evaluation of Track and Field Athletes

Effects of Running and Sprinting Loads on Achilles Tendon Structure and Recovery Process: A Longitudinal Ultrasound Imaging Study in Track and Field Athletes - Ultrasound Imaging Evaluation of Achilles Tendon Structure and Recovery Process in Track and Field Athletes

Status

Recruiting

Phases

Unknown

Study type

Interventional

Source

JPRN

Registry ID

JPRN-UMIN000060967

Enrollment

Registered

2026-03-20

Start date

2025-11-13

Completion date

Unknown

Last updated

2026-09-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Achilles tendon disorder

Interventions

Sprint running

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: 1. Members of the Gunma University School of Medicine Track and Field Team 2. Individuals with no history of orthopedic conditions affecting the lower limbs within the past three months 3. Individuals who can undergo measurement using an ultrasound imaging device 4. Individuals who have received an explanation of this study and have provided informed consent

Exclusion criteria

Exclusion criteria: 1. Individuals with a history of surgery on the foot or around the ankle 2. Individuals with a history of Achilles tendon rupture 3. Individuals with less than six months of athletic activity

Design outcomes

Primary

Measure	Time frame
Evaluation/Measurement Timepoints: Before exercise intervention, Immediately after exercise intervention, 6 hours after exercise intervention, 24 hours after exercise intervention, 48 hours after exercise intervention, 72 hours after exercise intervention Primary Outcome: Cross-sectional Area (CSA)	—

Secondary

Measure	Time frame
Evaluation/Measurement Timepoints: Pre-exercise intervention, Immediately post-exercise intervention, 6 hours post-exercise intervention, 24 hours post-exercise intervention, 48 hours post-exercise intervention, 72 hours post-exercise intervention Secondary Outcomes: Tendon thickness, fibrillar pattern, brightness distribution, dynamic creep response (change in free Achilles tendon length), gastrocnemius thickness, passive ankle dorsiflexion range of motion, isometric ankle plantar flexion strength, basic information (height, weight, gender, age), athletic history, training status, recovery time for each item	—

Measure

Time frame

Evaluation/Measurement Timepoints: Pre-exercise intervention, Immediately post-exercise intervention, 6 hours post-exercise intervention, 24 hours post-exercise intervention, 48 hours post-exercise intervention, 72 hours post-exercise intervention Secondary Outcomes: Tendon thickness, fibrillar pattern, brightness distribution, dynamic creep response (change in free Achilles tendon length), gastrocnemius thickness, passive ankle dorsiflexion range of motion, isometric ankle plantar flexion strength, basic information (height, weight, gender, age), athletic history, training status, recovery time for each item

—

Countries

Japan

Contacts

Public ContactTakumi Kobayashi

Gunma University Graduate School Graduate School of Health Sciences, Department of Health Sciences

kobatakku@gunma-u.ac.jp027-220-8972

Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Sep 19, 2026