Athletes
Conditions
Keywords
Muscle Stretching Exercises, Pain Threshold, Range of Motion, Articular, Muscle Strength, Athletes
Brief summary
This randomized, assessor-blinded, parallel-group comparative trial investigated the acute effects of foam rolling (FR) and proprioceptive neuromuscular facilitation (PNF) stretching used as warm-up strategies in amateur athletes. Following a standardized 5-minute aerobic cycling warm-up, participants were randomly allocated to either a foam rolling group or a PNF stretching group. Hamstring flexibility was the prespecified primary outcome. Isometric knee flexion strength, vertical jump performance, pressure pain threshold, and intervention-related perceived exertion were assessed as secondary outcomes. All performance outcomes were assessed before and immediately after the assigned intervention.
Detailed description
Foam rolling and proprioceptive neuromuscular facilitation stretching are commonly used as warm-up strategies to acutely improve flexibility. However, direct comparisons of their effects on flexibility and performance-related outcomes remain limited. This study was designed to compare the acute effects of foam rolling and proprioceptive neuromuscular facilitation stretching used as warm-up strategies in amateur athletes. Healthy amateur athletes aged 18 to 30 years were randomly assigned to either a foam rolling group or a proprioceptive neuromuscular facilitation stretching group. All participants first completed a standardized 5-minute light-intensity cycling warm-up. Participants in the foam rolling group performed unilateral hamstring foam rolling on the dominant lower limb for 3 sets of 30 seconds, for a total application time of 90 seconds. Participants in the proprioceptive neuromuscular facilitation stretching group performed four repetitions, each consisting of 5 seconds of maximal isometric hamstring contraction, 5 seconds of relaxation, and 20 seconds of passive stretching, for a total application time of 120 seconds. Hamstring flexibility was assessed using the sit-and-reach test. Isometric knee flexion strength was assessed using handheld dynamometry, vertical jump performance using a standing vertical jump test, and pressure pain threshold using pressure algometry over the hamstring region. Intervention-related perceived exertion was assessed immediately after the assigned intervention. The main outcome measures were assessed before and immediately after the intervention. Outcome assessors were blinded to group allocation.
Interventions
OTHERFoam Rolling
Participants performed unilateral hamstring foam rolling on the dominant lower limb in a long-sitting position on a firm, flat surface. The foam roller was positioned under the hamstring region, and participants slowly rolled back and forth between the ischial tuberosity and the popliteal fossa under sustained body-weight pressure. The protocol consisted of 3 sets of 30 seconds, for a total application time of 90 seconds. Participants were instructed to apply the maximum tolerable pressure that did not produce pain.
Participants received unilateral PNF stretching of the hamstring on the dominant lower limb in a long-sitting position with the knee fully extended. Each repetition consisted of a 5-second maximal isometric hamstring contraction, followed by 5 seconds of relaxation and 20 seconds of passive stretching. The therapist provided manual resistance during the isometric contraction and guided the participant into the stretch position. Four repetitions were performed, for a total application time of 120 seconds.
Sponsors
Acibadem University
The Scientific and Technological Research Council of Turkey
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
SINGLE (Outcomes Assessor)
Masking description
Outcome assessors were blinded to group allocation. Participants and therapists administering the interventions were not blinded.
Intervention model description
Participants were randomly assigned to one of two parallel groups: a foam rolling group or a PNF stretching group.
Eligibility
Sex/Gender
ALL
Age
18 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
* Age between 18 and 30 years * Being actively engaged in training or competition in amateur sport
Exclusion criteria
* Generalized hypermobility * History of hamstring injury within the previous 6 months * Diagnosed orthopedic pathology * Previous surgery involving the lower extremity or spine * Current low back pain * Any systemic or neurological disorder that could affect test performance or intervention safety
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Hamstring Flexibility Assessed by the Sit-and-Reach Test | Pre-intervention and immediately after the intervention | Hamstring flexibility was assessed using the Baseline® Sit and Reach Flexibility Tester. Participants sat with both knees fully extended, the lower limbs together, and the soles of the feet placed flat against the testing device. Participants reached forward as far as possible without flexing the knees. Three trials were performed, and the mean value was recorded in centimeters (cm). Higher values indicate greater flexibility. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Intervention-Related Perceived Exertion | Immediately after the intervention | Intervention-related perceived exertion was assessed immediately after the assigned intervention using a single-item 0-10 numerical rating scale (NRS), anchored from 0 (no exertion) to 10 (maximal exertion). Higher scores indicate greater perceived exertion. |
| Vertical Jump Performance | Pre-intervention and immediately after the intervention | Vertical jump performance was assessed using a standing vertical jump test. Standing reach height was first recorded. Participants then performed a countermovement jump and reached as high as possible. Vertical jump height was calculated as the difference between jump reach height and standing reach height. Three trials were performed, and the highest value was recorded in centimeters (cm). Higher values indicate greater vertical jump performance. |
| Isometric Knee Flexion Strength | Pre-intervention and immediately after the intervention | Isometric knee flexion strength was measured using a digital handheld dynamometer (J Tech Commander Muscle Tester). Participants were seated with the hips and knees flexed to 90°. The dynamometer was positioned on the posterior aspect of the lower leg, 5 cm proximal to the lateral malleolus. Participants performed maximal isometric knee flexion for 3 seconds. Three trials were performed with 60 seconds of rest between trials, and the highest force value sustained for more than 0.5 seconds was recorded in kilogram-force (kgf). Higher values indicate greater isometric knee flexion strength. |
| Hamstring Pressure Pain Threshold | Pre-intervention and immediately after the intervention | Pressure pain threshold was assessed over the hamstring region using a digital pressure algometer (Baseline FDK 10). Participants were positioned prone, and the algometer probe was applied perpendicular to the most sensitive point of the hamstring region. Pressure was gradually increased at approximately 1 kgf/cm² every 3 seconds until the participant first reported pain. Three measurements were performed with 20-second intervals between trials, and the lowest value was recorded for analysis. Higher values indicate a higher pressure pain threshold. |
Countries
Turkey (Türkiye)
Contacts
STUDY_DIRECTORElif E Bayraktar, asst. prof.
Acibadem University
PRINCIPAL_INVESTIGATORHayri E Yılmaz
Acibadem University
STUDY_CHAIRBirce B Çelik
Acibadem University
STUDY_CHAIRMahmut E Bükülmez
Acibadem University
STUDY_CHAIREren Çekiç
Acibadem University
Outcome results
None listed