Publications

Introduction: The gastrocnemius muscle plays a crucial role in plantar flexion and functional activities like jumping and running, with its viscoelastic properties influencing performance. This study aimed to compare the immediate effects of static, dynamic, and PNF stretching on gastrocnemius viscoelastic properties and functional performance.

Methods: This randomized controlled four-group study with outcomes assessed by a blinded assessor was conducted with 60 healthy adults (18–45 years) allocated to static stretching (SS), dynamic stretching (DS), Proprioceptive Neuromuscular Facilitation stretching (PNF), or sham stretching (control). Muscle viscoelastic properties (tone, stiffness, elasticity; MyotonPRO), ankle range of motion (ROM; digital goniometer), passive ankle dorsiflexion with the knee extended, flexibility (Sit and Reach Test), and functional performance (Single-Leg Hop Test) were assessed before and immediately after a single stretching session.

Results: DS produced significant within-group reductions in muscle tone and stiffness bilaterally (p<0.05), while no significant changes were found in elasticity. Right ankle dorsiflexion (DF) improved significantly only in the DS group (p<0.05). Passive ankle dorsiflexion with the knee extended increased within the DS group on the right and within the DS and PNF groups on the left (p<0.05). Flexibility and functional performance improved significantly in all stretching groups but not in the sham group (p<0.05). Between-group analyses revealed significant main effects of time and some time×group interactions; however, post hoc tests did not detect significant pairwise differences (p>0.05).

Conclusions: This four-condition comparison identified significant immediate within-group improvements in several mechanical and functional outcomes following dynamic stretching. However, post hoc pairwise comparisons did not establish superiority of any technique. Further adequately powered studies are needed to clarify the magnitude, persistence, and clinical relevance of between-group differences.

Keyword: functional performance, gastrocnemius, stretching, viscoelastic properties

Following a single stretching session, dynamic stretching showed immediate within-group changes in several gastrocnemius mechanical outcomes, while static, dynamic, and PNF stretching showed within-group improvements in sit-and-reach flexibility and single-leg hop performance. Pairwise between-group comparisons did not establish superiority of any technique; therefore, these findings do not support preferential selection of one stretching method. The results apply to immediate responses in healthy adults. Larger studies with repeated-session interventions and follow-up assessments are needed to determine between-group differences, their persistence, and their clinical relevance.