Vertical Jump PerformanceNCT06944652
Stretching to Improve Jumping Performance
A study testing Stretching in people with Vertical Jump Performance, run by University of Saskatchewan at 1 site in Canada.
Trial summary
The study involves comparison of an 8-week plantar flexor stretching program to a shoulder stretching program for improving vertical jump performance in adolescent athletes. Read more about this study
- Who is it for?
- Ages 12 to 17 yearsHealthy volunteers can take part
- Conditions the study is for
- Vertical Jump Performance
- What is being tested?
- Stretching
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 40 participants
- Where
- 1 siteCanada
- Study dates
- 28 Apr 2025to 30 May 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 12 to 17 years
- All sexes
- Healthy volunteers accepted
- Child
Who may be able to join
- Currently involved in a sport training program
Who cannot join
- Current or past injuries that might affect jumping performance or stretching the plantar flexors or shoulder joint
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Canada1 site, 1 recruiting
- Recruiting
College of Kinesiology University of Saskatchewan
Saskatoon, Saskatchewan, S7K 2X2
Philip Chilibeck, 3062303849, phil.chilibeck@usask.ca
About this study
Official title: Flexibility Training (Stretching) to Improve Jumping Performance
The study involves comparison of an 8-week plantar flexor stretching program to a shoulder stretching program for improving vertical jump performance in adolescent athletes.
Read the detailed description
Increasing flexibility may improve vertical jump performance. For example, being able to go deeper into a squat before jumping may allow for greater force development through the range of movement and this may transfer to greater vertical jump height. The study compares plantar flexor stretching to shoulder stretching for improving vertical jump performance in adolescent athletes. Athletes are being stratified by sex and maturity status (before or after estimated age at peak height velocity) and randomized to one of two groups: Plantar flexor stretching (2 sets of 6 stretches, 5 times per week) or the same volume of shoulder stretching. Before and after training, participants are being assessed for vertical jump and landing performance.
- Conditions
- Vertical Jump Performance
- Being tested
- Stretching
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
StretchingOther
Stretching of the plantar flexors or the shoulder joint
| Study group | Role | What they receive |
|---|---|---|
| Plantar flexor stretching | Experimental | Flexibility training (stretching) of the muscles at the back of the lower leg Receives: Other: Stretching |
| Shoulder stretching | Active comparator | Flexibility training (stretching) of the muscles surrounding the shoulder joint Receives: Other: Stretching |
What is being measured
The primary outcome is the main question the study is designed to answer.
Counter movement jump height
Counter movement jump height assessed on a force plate
Measured: Change over 8 weeks
Secondary outcomes (8)
Take-off velocity
Take-off velocity assessed on a force plate in the right and left limbs
Measured: Change over 8 weeks
Ground reaction force on take off
Ground reaction force on take off from a counter movement jump on a force plate in right and left limbs
Measured: Change over 8 weeks
Ground reaction force on landing
Ground reaction force when landing from a jumping on force plate in right and left limbs
Measured: Change over 8 weeks
Ground reaction force when landing from a standard height
Ground reaction force when landing from a height (150% of baseline counter movement jump height)
Measured: Change over 8 weeks
Functional dorsiflexor range of movement
Functional dorsiflexor range of movement assessed with an inclinometer in left and right limbs
Measured: Change over 8 weeks
Active dorsiflexor range of movement
Active dorsiflexor range of movement assessed with a goniometer in right and left limbs
Measured: Change over 8 weeks
Passive dorsiflexor range of movement
Passive dorsiflexor range of movement assessed with a goniometer in right and left limbs
Measured: Change over 8 weeks
Shoulder flexibility
Shoulder flexibility assessed with a goniometer in right and left limbs
Measured: Change over 8 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted25 Apr 2025
- Study start28 Apr 2025
- Primary completion28 Apr 2026 (estimated)
- Study completion30 May 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Vertical Jump PerformanceStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 40 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Saskatchewan
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Phil Chilibeck, University of Saskatchewan
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06944652
- Sponsor's protocol ID
- 4925
- Status last verified
- Feb 2026
- First submitted
- 17 Apr 2025
- Last updated
- 23 Feb 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 23 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Flexibility Training (Stretching) to Improve Jumping Performance
- ClinicalTrials.gov ID
- NCT06944652
- Acronym / sponsor ID
- 4925
- Conditions
- Vertical Jump Performance
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 40 participants (estimated)
- Lead sponsor
- University of SaskatchewanUniversity, hospital or other
- Study start
- 28 Apr 2025 (actual)
- Primary completion
- 28 Apr 2026 (estimated)
- Study completion
- 30 May 2026 (estimated)
- First posted
- 25 Apr 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The study involves comparison of an 8-week plantar flexor stretching program to a shoulder stretching program for improving vertical jump performance in adolescent athletes.
Detailed description
Increasing flexibility may improve vertical jump performance. For example, being able to go deeper into a squat before jumping may allow for greater force development through the range of movement and this may transfer to greater vertical jump height. The study compares plantar flexor stretching to shoulder stretching for improving vertical jump performance in adolescent athletes. Athletes are being stratified by sex and maturity status (before or after estimated age at peak height velocity) and randomized to one of two groups: Plantar flexor stretching (2 sets of 6 stretches, 5 times per week) or the same volume of shoulder stretching. Before and after training, participants are being assessed for vertical jump and landing performance.
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (participant)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Plantar flexor stretching | Experimental | Other: StretchingFlexibility training (stretching) of the muscles at the back of the lower leg |
| Shoulder stretching | Active comparator | Other: StretchingFlexibility training (stretching) of the muscles surrounding the shoulder joint |
Who may qualify
- Ages
- 12 to 17 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Child
Key inclusion criteria (1 listed)
- Currently involved in a sport training program
Key exclusion criteria (1 listed)
- Current or past injuries that might affect jumping performance or stretching the plantar flexors or shoulder joint
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| StretchingStretching of the plantar flexors or the shoulder joint | Other | Plantar flexor stretching, Shoulder stretching |
Primary outcome
Counter movement jump height
Time frame: Change over 8 weeks
Counter movement jump height assessed on a force plate
8 secondary outcomes
Take-off velocity
Time frame: Change over 8 weeks
Ground reaction force on take off
Time frame: Change over 8 weeks
Ground reaction force on landing
Time frame: Change over 8 weeks
Ground reaction force when landing from a standard height
Time frame: Change over 8 weeks
Functional dorsiflexor range of movement
Time frame: Change over 8 weeks
Active dorsiflexor range of movement
Time frame: Change over 8 weeks
Passive dorsiflexor range of movement
Time frame: Change over 8 weeks
Shoulder flexibility
Time frame: Change over 8 weeks
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 23 Feb 2026.
- Individual participant dataSharing planned: No
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Stretching in people with Vertical Jump Performance, run by University of Saskatchewan at 1 site in Canada.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 23 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Philip Chilibeck, PhD (306-966-1072, phil.chilibeck@usask.ca), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Counter movement jump height (time frame: Change over 8 weeks). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 23 Feb 2026; AzTrials last refreshed its copy on 27 Oct 2026.