The Single Leg Bridge Test (SLBT) as a field test to measure hamstring strength in young footballers

Purpose: The muscle strength of the hamstrings is often reported as asymmetric in footballers and is associated with the occurrence of muscle injuries. Therefore, discriminating, reproducible and valid screening tests are sought. Methodology: The objectives of this study were: to assess the muscle strength profile of the hamstrings with the Single Leg Bridge Test (SLBT) in U17 and U19 football players, to calculate the asymmetry of muscle strength and to classify the results according to 3 performance levels. This cross-sectional study included 37 young footballers, 20 U17 and 17 U19. The SLBT was performed for the left and right leg. History of hamstring muscle injury has been identified up to 2 years prior to SLBT. Results: A significant difference was found between the left and right side (P = 0.01), particularly among U17s (P = 0.03). The asymmetry of strength was 23% for the U17s and 17% for the U19s. The performance considered “poor” (21–30 repetitions) was different between U17 and U19 (P < 0.05). No association was found with a history of hamstring muscle injury. Conclusion: The SLBT is an adequate field test for the assessment of hamstring strength in order to detect hamstring muscle asymmetry in young footballers. This test requires little equipment, money, and can be performed on multiple players simultaneously. Classification according to performance (number of repetitions) adds practical value in order to develop individual muscle building programs based on the calculated asymmetry in the young footballers.