Reliability of isokinetic hip flexor and extensor strength measurements in healthy subjects and athletes: A systematic review and meta-analysis

Background: The objective of this systematic review and meta-analysis was to examine the reliability of isokinetic measurements of hip strength in flexion and extension in healthy subjects and athletes. Methods: The databases used were Web of Science, SCOPUS, Medline and PubMed. R was used for all statistical analyses. Results: Hip flexion shows moderate reliability in the supine position (ICC = 0.72; 95% CI: 0.46–0.99) and good reliability in the standing position (ICC = 0.79; 95% CI: 0.54–1.04). Hip extension shows excellent reliability in the supine position (ICC = 0.90; 95% CI: 0.85–0.96) and moderate reliability in the standing position (ICC = 0.72; 95% CI: 0.48–0.96). Flexion of 120^◦/s and 180^◦/s showed excellent reliability (ICC = 0.93; 95% CI: 0.85–1.00), (ICC = 0.96; 95% CI: 0.92–1.01). The 60^◦/s and 120^◦/s extension showed good reliability (ICC = 0.90; 95% CI: 0.82–0.98), (ICC = 0.87; 95% CI: 0.75–0.99). The 180^◦/s extension presented excellent reliability (ICC = 0.93; 95% CI: 0.82–1.03). Conclusions: The standing position shows good reliability for hip flexion and the supine position shows excellent reliability for hip extension, both movements have excellent reliability at velocities between 120^◦/s to 180^◦/s.