An interventional study of Instrument-Assisted Soft Tissue Mobilization and Static Stretching in Hamstring Tightness, sponsored by GÖKHAN MARAŞ. Recruiting at 1 site in Turkey (Türkiye). Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-04.
Sponsored by GÖKHAN MARAŞ · Not applicable, Interventional, and Treatment
This study compares two treatments for people with tight hamstring muscles (the muscles at the back of the thigh): instrument-assisted soft tissue mobilization (IASTM) and static stretching. Both are commonly used by physical therapists to improve flexibility, but few studies have looked at their effects beyond a few days after treatment ends.
Forty-six adults with hamstring tightness will be randomly assigned to one of two groups. One group will receive IASTM, and the other will receive static stretching. Both treatments will be given 3 times per week for 4 weeks (12 sessions total).
Researchers will measure flexibility (knee extension range of motion), pressure pain threshold, and physical performance (vertical jump and single-leg hop distance) at three time points: before treatment, 3 days after the last session, and 8 weeks after treatment ends. The goal is to find out which treatment provides better short-term and longer-term benefits.
Hamstring muscle tightness is a common musculoskeletal condition that can limit hip and knee range of motion, reduce athletic and functional performance, and contribute to other conditions such as patellofemoral pain, patellar tendinopathy, and low back pain. Static stretching has long been used to address hamstring tightness, with systematic reviews suggesting that 6-8 weeks of regular stretching can produce lasting flexibility gains. Instrument-assisted soft tissue mobilization (IASTM) has more recently emerged as an alternative technique, with proposed mechanisms including controlled microtrauma that stimulates an inflammatory response and collagen remodeling in soft tissue.
Most existing studies comparing static stretching and IASTM for hamstring tightness have examined only single-session or short-term (immediate post-treatment) effects. Long-term follow-up data (≥8 weeks) are limited, making it difficult to determine whether treatment-related gains in flexibility, pain sensitivity, and functional performance are sustained over time.
This randomized controlled trial will enroll 46 participants with hamstring tightness, defined as hip flexion range of motion \<65° on the Straight Leg Raise (SLR) test with no neurological signs. Participants will be randomly allocated (computer-generated randomization) to one of two equal groups (n=23 each):
Group 1 (IASTM): Participants will receive instrument-assisted soft tissue mobilization applied to the hamstring muscle group using a stainless-steel instrument, scanning technique, distal-to-proximal direction, for 5 minutes per session.
Group 2 (Static Stretching): Participants will receive manual static stretching of the hamstring muscle group, performed in 5 repetitions of 30 seconds of stretch followed by 30 seconds of rest (5 minutes total per session).
Both interventions will be delivered 3 times per week for 4 weeks (12 sessions total) by a physical therapist with over 10 years of clinical experience in orthopedic rehabilitation and manual therapy.
Outcome assessments will be performed by a blinded assessor independent of treatment delivery, at three time points: baseline (pre-treatment), short-term (3 days after the final session), and long-term (8 weeks after intervention completion). Outcome measures include:
Statistical analysis will include two-way repeated-measures ANOVA to assess time and group-by-time interaction effects, with Bonferroni-corrected post hoc comparisons where appropriate.
This is the only study on the registry with GÖKHAN MARAŞ as lead sponsor.
Counted across the registry records on this site, refreshed daily.
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Exclusion Criteria:
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You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive instrument-assisted soft tissue mobilization (IASTM) applied to the hamstring muscle group using a stainless-steel instrument in a scanning technique, distal-to-proximal direction, for 5 minutes per session, 3 times per week for 4 weeks (12 sessions total).
Other: Instrument-Assisted Soft Tissue Mobilization
Participants will receive manual static stretching of the hamstring muscle group, performed in 5 repetitions of 30 seconds of stretch followed by 30 seconds of rest (5 minutes total per session), 3 times per week for 4 weeks (12 sessions total).
Other: Static Stretching
Participants will receive instrument-assisted soft tissue mobilization (IASTM) applied to the hamstring muscle group using a stainless-steel instrument in a scanning technique, distal-to-proximal direction, for 5 minutes per session, 3 times per week for 4 weeks (12 sessions total).
Participants will receive manual static stretching of the hamstring muscle group, performed in 5 repetitions of 30 seconds of stretch followed by 30 seconds of rest (5 minutes total per session), 3 times per week for 4 weeks (12 sessions total).
Change in Knee Extension Range of Motion (Flexibility)
Knee extension range of motion during 90° hip flexion, measured with a digital inclinometer, as an indicator of hamstring flexibility.
Time frame: Baseline, 3 days after final session (short-term), and 8 weeks after intervention completion (long-term)
Started Sep 2026 (actual). Primary completion is estimated for Dec 2026, 3 months after the start.
Since we started tracking on Sep 25, 2026, the dates moved once, on Nov 4, 2026: primary completion Feb 2027 → Dec 2026 and completion Feb 2027 → Dec 2026.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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