Instrument-assisted soft tissue mobilization and proprioceptive neuromuscular facilitation techniques improve hamstring flexibility better than static stretching alone: a randomized clinical trial

ABSTRACT

Objectives: Tight hamstrings contribute to inefficiency of movement and increased risk for injury. Static stretching is the most common intervention for this problem, but the use of alternatives like instrument-assisted soft tissue mobilization (IASTM) and proprioceptive neuromuscular facilitation (PNF) is increasing among clinicians. This study examined two prospective studies with the common aim of demonstrating the effectiveness of IASTM or PNF over static stretching for improving hamstring tightness.

Methods: Nondisabled adults were recruited on a university campus. IASTM study: N = 17 (11 males and 6 females). PNF study: N = 23 (7 males and 16 females). Hip flexion range of motion was measured with a passive straight leg raise (for IASTM) or active straight leg raise (for PNF) before and after stretching. Participants performed a self-static stretch on one leg and received the alternative intervention on the contralateral leg. The two studies were analyzed separately for reliability indices and significant differences between interventions.

Results: Hip flexion measures showed good reliability in both studies (intraclass correlation coefficient = 0.97) with a minimal detectable change of <4.26. Both studies showed significant interactions between time and intervention (p < 0.05). Follow-up analyses revealed PNF and IASTM interventions resulted in greater increases in hip flexion range than static stretching.

Discussion: These findings demonstrate the effectiveness of PNF and IASTM techniques over static stretching for hamstring flexibility. These interventions provide more efficient alternatives for improving flexibility in the clinic, allowing greater progress in a shorter period of time than an equivalent static stretching program.

Level of Evidence: 1b.

KEYWORDS:

• Flexibility
• range of motion
• knee flexors
• active straight leg raise
• passive straight leg raise
• hip flexion
• lower extremity
• digital inclinometer

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplemental Material

Supplemental data can be accessed here.

Additional information

Notes on contributors

Leanna J. Gunn

Leanna J. Gunn received a baccalaureate degree in Kinesiology from Augusta University before attending University of South Carolina and receiving a Doctorate of Physical therapy. She has presented a poster on manual therapy techniques at the national Combined Sections Meeting and currently works as a home health physical therapist in Orangeburg, South Carolina.

Jill Campbell Stewart

Jill Campbell Stewart is a physical therapist and researcher with a PhD in Biokinesiology. Her area of expertise is in the behavioral and neural correlates of skilled motor behavior. Currently, she is an assistant professor in the Doctor of Physical Therapy Program at the University of South Carolina.

Brittany Morgan

Brittany S. Morgan received her Doctorate of Physical Therapy from University of South Carolina and currently practices full time in the home health setting. During her career, she provided a poster presentation at the South Carolina American Physical Therapy Association (SCAPTA) conference.

Steven T. Metts

Steven T. Metts is a physical therapist currently working in the Home Health setting. He is a graduate of the University of South Carolina Doctor of physical therapy program. He has presented his research poster at the South Carolina American Physical Therapy Association (SCAPTA) conference.

Justin M. Magnuson

Justin M. Magnuson is a physical therapist with a Bachelor's Degree in exercise science from Lander University and a Doctor of physical therapy degree from the University of South Carolina.

Nicholas J. Iglowski

Nicholas Iglowski graduated with a Doctorate of Physical Therapy from the University of South Carolina in 2016. He holds undergraduate degrees in History and Asian Studies from Furman University. He currently works as a Home Health Physical Therapist in Columbia, SC.

Stacy L. Fritz

Stacy L. Fritz received her Master of Science in Physical Therapy from the University of Kentucky before working as a physical therapist in a variety of health-care settings. Through her diverse experiences, she became acutely aware of the need for research to support physical therapy interventions and decided to pursue a doctoral degree in Rehabilitation Science at the University of Florida. She is currently an Associate Professor and Director of the Physical Therapy program at the University of South Carolina. Her research focuses are: 1) rehabilitation of individuals with chronic neurological insult, 2) exercise for individuals with chronic disability, and 3) walking speed as a vital sign of function.

Catherine Arnot

Cathy F. Arnot is a physical therapist who is board certified orthopedic clinical specialist, certified in manual therapy from the University of St Augustine and is a Fellow of the American Academy of Orthopedic Manual Physical Therapy. She has several publications on the efficacy of manual therapy techniques. She has also presented numerous posters at national conferences regarding instrument assisted soft tissue mobilization, kinesiotaping, and ultrasound imaging. She has been a clinical associate professor at the University of South Carolina since 2006. She also provides team coverage to the United States Olympic Shooting team and serves on the International Sport Shooting Medical Committee.