INTRODUCTION: In many intermittent team sports capacities such as speed, agility and explosiveness are important for performance and are evaluated by sprint-, agility- and strength tests. Earlier studies have shown strong correlations between strength in the two leg squat exercise and sprint performance in various distances but not in sprint performance in agility. Studies evaluating squat strength predominantly perform tests on two legs even when they test athletes involved in intermittent sports where sprinting and agility are common features. Thus, the purpose of this study was to investigate the correlation between maximal strength in a one leg squat (Bulgarian split squat) and acceleration capacity in various sprint distances and agility.

METHODS: The test group consisted of 19 men (mean age 24 ± 2 years ) with experience in intermittent team sports. Acceleration capacity was assessed by sprint tests at 5, 10 and 20 meters and agility was evaluated using the zigzag agility test. The timing was made using photocells (Muscle lab,Ergotest Technology,Norway). The Bulgarian split squat was performed in a smith machine with the barbell on the shoulders to a depth of 110 degrees between tibia and femur.

RESULTS: The results show significant correlation between maximal strength in the Bulgarian split squat and sprint capacity in the 5 and 10 meter sprint test (R_p= -0,56; p<0.01) as well as the agility test. Maximal strength relative to bodyweight showed significant correlation with the 5 and 20 meter sprint (R_p=-0,62; p< 0,01) as well as the agility test. The zigzag agility test also showed significant correlation between all distances in the sprint tests (p<0.01).

CONCLUSION: The results from this study show that there maximal strength in one leg correlate significantly with both acceleration capacity and agility. Implementing one leg exercises in the strength and conditioning routine can be useful for athletes in intermittent sports wanting to improve agility and short sprinting capacity. Further implications is that the Bulgarian split squat could be a more functional test for agility performance than the squat on two legs which  predominantly is being used today.