Immediate Effect of Graston Technique Versus PNF Stretching on Hamstring Flexibility in Undergraduate Students

Background: 
Hamstring tightness is frequently observed among undergraduate students, mainly due to prolonged 
sitting and reduced physical activity. Decreased flexibility can limit range of motion, alter posture, 
and increase the risk of musculoskeletal problems such as low back pain and knee dysfunction. 
Various therapeutic approaches, including Proprioceptive Neuromuscular Facilitation (PNF) 
stretching and the Graston Technique (GT), are commonly used to improve flexibility and muscle 
function  
Objective: 
To compare the immediate effects of the Graston Technique and PNF stretching on hamstring 
flexibility in undergraduate students. 
Methodology: 
A randomized controlled trial was conducted on 50 undergraduate male students aged 18–25 years. 
Participants were divided into two groups: Group A received PNF stretching and Group B received 
the Graston Technique. Hamstring flexibility was assessed using the Active Knee Extension (AKE) 
test before and after intervention. Both interventions were applied according to standardized 
protocols. Statistical analysis was performed to determine within-group and between-group 
differences. 
Results: 
Both groups demonstrated statistically significant improvement in hamstring flexibility following 
intervention (p < 0.001). However, the Graston Technique group showed a greater reduction in AKE 
values compared to the PNF group. The difference between the groups was statistically significant (p 
< 0.05), indicating superior effectiveness of the Graston Technique. 
Conclusion: 
Both PNF stretching and the Graston Technique are effective in improving hamstring flexibility 
immediately after treatment. However, the Graston Technique provides greater improvement and may 
be considered a more effective intervention for immediate results. 
Keywords: 
Hamstring tightness, Graston Technique, PNF stretching, flexibility, range of motion, students.