Relationship between sitting duration and hamstring flexibility in young adults: A narrative review

Background: Prolonged sitting has become increasingly prevalent among young adults due to academic and occupational demands. Sustained sitting maintains the hips in a flexed position, which may contribute to reduced hamstring flexibility over time.
Objective: To examine the relationship between sitting duration and hamstring flexibility in young adults using the Active Knee Extension (AKE) test as the primary outcome measure.
Methods: A narrative literature review was conducted using PubMed and Google Scholar databases. Studies were included if they involved young adults aged 18–35 years, evaluated sitting duration and hamstring flexibility, used the AKE test as the primary outcome measure, employed cross-sectional or observational study designs, and were published between 2017 and 2026. Seven studies met the inclusion criteria and were included in the review.
Results: All seven studies reported an association between prolonged sitting duration and reduced hamstring flexibility. Participants with longer sitting durations demonstrated greater hamstring tightness than those with shorter sitting durations. The AKE test was the outcome measure across included studies and demonstrated reduced hamstring flexibility with increasing sitting duration. Findings support an association between sitting duration and hamstring flexibility.
Conclusion: The available evidence supports an association between prolonged sitting duration and reduced hamstring flexibility in young adults. These findings highlight the importance of assessing hamstring flexibility in sedentary young adults. Further longitudinal and interventional studies are required to establish causality and evaluate preventive physiotherapy strategies.