Immediate effect of instrument-assisted soft tissue... : Journal of the International Society of Physical and Rehabilitation Medicine (2025)

Introduction

A sedentary lifestyle is a major risk factor across a spectrum of preventable diseases that lower the quality of life¹. The presence of technological advances also has counteraccusations for changes in people’s lifestyles. World Health Organization has linked physical inactivity as the fourth leading risk factor accounting for 6% of global deaths worldwide².

Meanwhile, more than 80% of the world’s adolescent population also does insufficient physical activity. Incompletely low or decreased levels of physical activity are frequently the result of inactivity during leisure and sedentary behavior at work and home. A proportion of women is found to be more likely to adopt a lifestyle with less physical activity than men in various parts of the world². A sedentary lifestyle can lead to many problems like the tightness of muscles, decreased joint range of motion, reduced flexibility, and balance hampering the daily activities of an individual. The person who is sitting all day, such as a student, has adaptive changes taking place that can shorten the hip muscles¹.

Prolonged sitting causes changes in pelvic position, that is, tilt, which causes the hamstring into a shortened position. Prolonged sitting puts the load on the muscle with a large amount of force which increases the risk of injury¹. Hamstring tightness is prevalent among adolescents aged 18–25. Hamstring muscles are frequently associated with movement dysfunction at the lumbar spine and pelvis and have been linked to low back pain and gait abnormalities. Limited flexibility resulting from hamstring tightness triggers neuro-musculoskeletal symptoms, thereby decreasing strength, stability, flexibility, and other related factors³.

The lower kinetic chain is known to be affected by hamstring tightness, which causes biomechanical alterations. Short hamstring can lead to prolonged forefoot loading, which can lead to increased plantar fascia stress and an increase in plantar pressure⁴.

Muscle tightness can affect the normal length-tension relationship of a muscle which can lead to altered kinematics and joint stress. Due to these factors, abnormal neuromuscular control, seen with improper muscle activation sequence or firing order, can result in the development of compensations of the body and decrease movement efficiency⁴.

Hamstring tightness is one of the factors that affect dynamic balance because it loses the ability to deform while being stretched. This inability results in reduced hip flexion, altered hip extension, and a posterior tilt of the pelvis, which leads to decreased lumbar lordosis and back pain. Hamstring tightness also leads to increased quadriceps activity, which could lead to tendinopathies. The control of the lumbar spine and the lumbo-pelvic-hip complex is important to maintain stability and balance, and this is why a posteriorly tilted pelvis caused by hamstring tightness alters proprioception and balance⁵.

Soft tissue restrictions have been linked to poor flexibility and dynamic balance. To decrease the soft tissue restrictions and ultimately increase flexibility and dynamic balance, soft tissue mobilization techniques such as myofascial release technique and instrument-assisted soft tissue mobilization have been used⁵.

Soft tissue mobilization (STM) is a manual technique used by therapists to manipulate and mobilize scar tissue within soft tissue. The theory behind manual therapy is to mobilize fibroblast materials and create microtrauma while allowing the body to continue to physiologically change. Soft tissue mobilization techniques were introduced to aid in the breakdown of myofascial adhesions⁶.

Instrument-assisted soft tissue mobilization (IASTM) and myofascial release technique (MFR) are manual therapy methods analogous in mechanism of action, theoretical bases, and proposed fascial effects. Since the therapies are related in several aspects and often lack research support for the proposed benefits, choosing the most effective course of treatment in an individual patient context may be difficult⁷.

Instrument-assisted soft tissue mobilization, or simply IASTM, is a new range of tools that enables clinicians to efficiently detect and treat individuals diagnosed with soft tissue dysfunction. IASTM therapy is based on Cyriax principles that deep friction tissue massage improves tissue movement, prevents scar tissue formation, and generates a local inflammatory response. The method differs from other techniques by using specially designed instruments to apply multidirectional pressure to soft tissues. The instruments theoretically give a mechanical advantage by allowing clinicians greater force transmission than with hands alone. The advantage may facilitate a clinician’s ability to detect altered tissue properties^7,8.

Myofascial release (MFR) is a commonly employed manual technique aimed at promoting uninterrupted tissue stretching and enhancing the flexibility of soft tissues through compression. It helps in restoring restricted fascia and improving muscle length by utilizing compression to facilitate continuous stretching of the relevant tissues. MFR is focused on the application of gradual, continuous pressure to restricted fascial layers for 120–300 seconds by commonly using the foam roller^5,9.

This study will add literature to the field of IASTM and MFR and may help weigh in on conflicts of interest regarding hamstring flexibility and dynamic balance and help to choose the most effective course of treatment for an individual.

Aim of the study

The aim of this study was to determine the immediate effect of IASTM versus MFR on hamstring flexibility and dynamic balance among young adults.

Objective of the study

The objective of the study was to compare the effects of:

• IASTM on hamstring flexibility and dynamic balance among young adults.
• MFR on hamstring flexibility and dynamic balance among young adults.

Methodology

This is a comparative study.

Randomization: Random sampling was done using a chit system, which was under observation of IA and MA. A bowl was filled with chits of group 1 and group 2. Participants were asked to pick up one chit and as per the chit, they were included in the particular group.

Inclusion Criteria: Participants who were willing to participate and were of both genders were included in the study. Participants of age group between 18 and 25 years. Participants with normal BMI (18.5–24.9) and participants with tight hamstring.

Exclusion Criteria: Participants who were diagnosed with any lower limb injuries such a fracture, sprains and strains, participants diagnosed with any neurological and cardiovascular conditions, as reported by the participants. Participants with psychiatric disorders as reported.

Procedure: Base-line anthropometric traits as well as the history of the participants were obtained by personal interview. Questions of the interview were closed-ended. Base-line anthropometric traits and history included age, gender, BMI, past ailment history, neuromuscular, cardiovascular, and psychiatric abnormalities. Subjects (N=80) fulfilling the inclusion and exclusion criteria were asked to give their consent for participation.

The selected participants were randomly divided into 2 groups (group A and group B) of 40 participants each. Group A—MFR and group B—IASTM. Before the maneuver hamstring muscle tightness was measured using 90-90 SLR test. Participant was first taken in supine position with the hips and knees flexed to 90 degrees and the lumbar spine in neutral position. The participant was then asked to stabilize this position by grabbing onto the back of the thighs and to actively extend the knee on the side to be tested while her lumbar spine remained in neutral position. The angle of knee flexion was measured using goniometer, and it was noted⁸. The lower limb length was measured by the measuring tape by taking the distance from the subject’s anterior superior iliac spine to the medial malleolus of the ankle and recorded as the lower limb length⁸.

The pretest flexibility and dynamic balance were measured using the sit and reach test and Y balance test. For the sit-and-reach test, the participant was instructed to sit on the floor with legs stretched out straight ahead. The participant was asked to remove the Shoes and to place the sole of the feet flat against the box. Both knees were locked and pressed flat to the floor, with the palms facing downward and the hands-on top of each other or side by side; the subject reached forward along the measuring line as far as possible and helds that position for at least 1–2 seconds while the distance was recorded. The test was performed 3 times, and the average value was taken⁹. For the Y balance test, the participant was asked to stand unipedally in the center of the platform and pinched the waist with both hands, the thumb of the foot facing forward against the center line of the anterolateral scale while maintaining a unipedal standing posture. The contralateral foot was asked to extend as far as possible in all three directions to push the scale, and the values corresponding to the scale were recorded (to the nearest five centimeters). The test was performed three times in each direction and the average value was taken. The final score of the YBT was based on the unilateral side and the average of the scores of the 3 directions with the length of the lower limb taken¹⁰.

MFR, Foam roller was given in group A to release the hamstring muscle. The participant was placed in the prone position, and the part to be treated was completely exposed to avoid hindrance while treating. The treatment was applied to the full length of the muscle group, from the ischial tuberosity to the popliteal fossa, moving the roller both proximally and distally. Light pressure was used for ~10 seconds, and then advancing strokes increased to moderate pressure, with 10–30 seconds of treatment over adhesions¹¹.

IASTM, M2T blade was used on group B to release the muscles of the posterior aspect of the thigh. The participant was placed in the prone position, and the part to be treated was completely exposed to avoid hindrance while treating. Emollient was used to minimize the friction between the tissue and the blade. Adhesions were assessed with the blade in both upward and downward direction; moderate pressure was applied over the tissue while holding the blade at 45 degrees, slack was removed, and strokes were given in both directions to the full length of the muscle¹¹.

Both the treatment was given for 3.5 minutes on both the dominant and nondominant leg based on the previous researches. After the manoeuvre post-test flexibility and dynamic balance were measured by using the sit and reach test and y balance test¹¹. Postanalyses recorded.

Outcome Measures: Sit and Reach Test and Y-Balance tool score.

Data analysis

Descriptive statistics of mean age and BMI were analyzed. A paired t test was used to compare the flexibility and dynamic balance among participants. The alpha level was set at 0.05.

Results

Participants characteristics

The study included a total of 80 participants, 40 in group A and 40 in group B. The average age of group A (21.8±1.42393) years and group B (21.03±1.97367) years with a mean total of 21.42 (±1.749495) years. The average BMI of group A (22.3±1.89134) and group B (21.783±2.30008) with a mean total of 22.055 (±2.105636) kg/m². Demographic details are further discussed and demonstrated in Table 1 and Graphs 1 and 2.

Within groups results

Group A

The analysis of hamstring flexibility and dynamic balance was done by analyzing the pre and post-sit and reach and composite scores of Y-BT, respectively. The analysis revealed that the mean for preflexibility and postflexibility for group A was 21.2023 and 25.8927, respectively. The analysis revealed that the mean for predynamic and postdynamic balance for group A was, pre-right 28.5218, pre-left 28.7091, and post-right 30.2199, post-left 30.4345. This is further discussed and demonstrated in Table 2 and Graph 3.

Group B

The analysis of hamstring flexibility and dynamic balance was done by analyzing the pre-sit and post-sit and reach and composite scores of Y-BT, respectively. The analysis revealed that the mean for preflexibility and postflexibility for group B was 26.0293 and 29.2973, respectively. The analysis revealed that the mean for predynamic and postdynamic balance for group B was, pre-right 28.916, pre-left 28.8195 and post-right 30.6483, post-left 30.4125. This is further discussed and demonstrated in Table 3 and Graph 4.

Between the groups' results

The analysis revealed that the mean for preflexibility and postflexibility for group A was 21.2023 and 25.8927, respectively. The analysis revealed that the mean for preflexibility and postflexibility for group B was 26.0293 and 29.2973, respectively. The analysis revealed that the mean for predynamic and postdynamic balance for group A was, pre-right 28.5218, pre-left 28.7091, post-right 30.2199, post-left 30.4345. The analysis revealed that the mean for predynamic and postdynamic balance for Group B was, pre-right 28.916, pre-left 28.8195, post-right 30.6483, post-left 30.4125.

A paired sample t test was conducted to determine the relationship between the 2 groups, ie, group A and group B. The results indicate the group A, precomposite and postcomposite score right [t(39)=−3.731, P=0.001<0.05], precomposite and postcomposite score left [t(39)=−3.334, P=0.002<0.05] and pre and post-sit and reach [t(39)=−7.895, P=0.000<0.05] and the group B, precomposite and postcomposite score right [t(39)=−3.585, P=0.01<0.05], precomposite and postcomposite score left [t(39)=−5.086, P=0.000<0.05] and pre-sit and post-sit and reach [t(39)=−6.328, P=0.000<0.05] (Tables 4 and 5).

Discussion

The prevalence of hamstring tightness is very high in college-going students of the age group 18–25. Hamstring tightness affects musculoskeletal imbalance by limiting flexibility, static and dynamic balance, pain, and movement dysfunction. The present study was conducted to determine the best method for reducing pain and improving hamstring flexibility and dynamic balance. In this comparative experimental study design, 80 subjects with hamstring tightness were randomly divided into 2 groups, where group A received MFR and group B received IASTM, this study concluded that both the MFR and IASTM were equally effective for treating hamstring dynamic balance and flexibility but the IASTM is more effective for improving the flexibility.

As per Findley, both techniques aim to manipulate the fascia and soft tissues, which can increase circulation to the affected area, promote oxygen and nutrient delivery, and remove metabolic waste. This improved vascular response can facilitate tissue healing and reduce muscle tightness. The reduction of fascial restrictions and improvement in the sliding properties of the muscle and surrounding tissues can contribute to both increased flexibility and better dynamic balance. While MFR primarily uses manual techniques to achieve these benefits, IASTM uses tools to apply mechanical pressure more precisely. Despite the different methods, both techniques aim to optimize the physiological environment of the soft tissues, contributing to their effectiveness in reducing pain and improving overall function¹⁰.

One possible explanation for the superior effect of IASTM on hamstring flexibility could be its unique mechanical action on soft tissues. IASTM uses specifically designed instruments to apply deeper and more targeted pressure, which can break down adhesions, scar tissue, and fascial restrictions more effectively than manual techniques like MFR. The mechanical leverage provided by the instruments may allow for greater precision and control, resulting in enhanced tissue extensibility. Additionally, IASTM has been shown to promote collagen realignment and tissue remodeling, which can further contribute to improved flexibility. In contrast, MFR, though effective, may not achieve the same degree of localized, mechanical stimulation, which could account for the differences observed in flexibility improvements between the 2 techniques¹².

As per Kim and colleagues, IASTM on flexibility could be its influence on neurological factors. IASTM stimulates mechanoreceptors in the skin and underlying tissues, which may lead to a reduction in muscle tone through neural pathways. This decrease in muscle tone can enhance muscle relaxation, allowing for a greater range of motion and flexibility. The scraping or gliding motions involved in IASTM might also activate proprioceptive mechanisms, leading to improved body awareness and dynamic balance, contributing further to increased flexibility. On the other hand, MFR may not provide the same level of neuromuscular stimulation, which could explain its comparatively lower effect on flexibility¹³.

There was another study conducted by Arshad and colleagues, among patients with chronic heel pain. The current study concluded that IASTM is more effective than MFR in reducing pain and improving functional mobility of the foot and ankle in chronic pain of the heel¹³. The previous study by Doeringer and colleagues was conducted on 33 participants between the age groups of 18–35 years old with bilateral hamstring tightness. They used 2 interventions, IASTM and Therapeutic cupping, and they concluded that both techniques impacted hamstring mobility during a single treatment using only an IASTM without any additional therapeutic intervention¹⁴.

Limitation and future scope

There are a few limitations to this study. First, the results might have been affected by a smaller sample size, some of the participants were asked to repeat failed trials that may have caused training effects. Future studies can be taken up on larger sample sizes, and age-based and gender-based subgroups can be created. Due to the short duration of treatment intervention, it is difficult to evaluate long-term effects.

Conclusions

It has been concluded that both IASTM and MFR have a significant effect on dynamic balance and flexibility, but IASTM is more effective to improve the flexibility.

CRediT author statement

Sonali Saxena & Sonali: data collection; Ifra Aman: manuscripts writing; Mohd Asif: data analysis; Ghazala Khan & Kalpana Zutshi: Reviewing and re-writing.

Ethical approval

Ethical was taken from the Ethical Committee of the Institution.

Funding

There is no source of funds for this study.

Declaration of competing interest

The authors declare that they have no financial conflict of interest with regard to the content of this report.

Data availability statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Declaration of generative AI and AI-assisted technologies in the writing process

No AI tools/services were used during the preparation of this work.

References