IASTM vs. Static Stretching for Hamstring Tightness: Short- and Long-Term Effects

NCT07838844 | Not Yet Recruiting

• 1 other identifier: IASTM-HAM-2026-01
• Study Type: interventional
• Target: 46
• Locations: 0 countries
• Sites: N/A

Brief Summary

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.

Conditions

Hamstring Tightness

Keywords

Hamstring Tightness; Instrument-Assisted Soft Tissue Mobilization; IASTM; Static Stretching; Flexibility; Pressure Pain Threshold; Range of Motion

Outcome Measures

Primary Outcomes (1)

• 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.

  Baseline, 3 days after final session (short-term), and 8 weeks after intervention completion (long-term)

Study Arms (2)

IASTM

EXPERIMENTAL

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

Static Stretching

ACTIVE COMPARATOR

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

Interventions

Instrument-Assisted Soft Tissue Mobilization OTHER

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).

IASTM

Static Stretching OTHER

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).

Static Stretching

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18 years or older
• Hamstring tightness, defined as hip flexion range of motion \<65° on the Straight Leg Raise (SLR) test, without neurological signs
• No diagnosed chronic musculoskeletal or systemic disease
• Signed informed consent form

You may not qualify if:

• Previous trauma or surgical operation involving the lower extremity
• Neurological symptoms radiating to one or both lower extremities due to hamstring injury, spinal pathology, or sciatic nerve involvement
• Ankle instability
• Pregnancy
• Neurological signs elicited during the Straight Leg Raise (SLR) test
• Hyperalgesia, hematoma, varicose veins, or active skin infection in the lower extremity

Sponsors & Collaborators

• GÖKHAN MARAŞ: lead

MeSH Terms

Interventions

Muscle Stretching Exercises

Intervention Hierarchy (Ancestors)

Exercise Therapy; Rehabilitation; Aftercare; Continuity of Patient Care; Patient Care; Therapeutics; Physical Therapy Modalities; Exercise; Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Selcuk University

Model Details: Two parallel groups (IASTM and Static Stretching) receiving 12 sessions over 4 weeks, with blinded outcome assessment at baseline, short-term (3 days post-intervention), and long-term (8 weeks post-intervention) follow-up.

Study Record Dates

• First Submitted: September 18, 2026
• First Posted: September 24, 2026
• Study Start: September 1, 2026
• Primary Completion (Estimated): February 1, 2027
• Study Completion (Estimated): February 1, 2027
• Last Updated: September 24, 2026

Record last verified: 2026-09