OBJECTIVES: The purpose of our study was to evaluate the effectiveness of an 8-week core muscle strengthen functional training program in improving balance, endurance and speed.

METHODS: The research was conducted in February and March 2019 at the Harkány Sports Hall with the youth football team in Hungary. Our study was a prospective, longitudinal, quantitative study with convenience sampling. There were 15 players in our research who participated in U16 and U19 championships. Players were evaluated with the following tests: Star Excursion Balance Test (SEBT), Flamingo Balance Test (FBT), 20m Endurance Pendulum running, Plank Core Strength and Stability Test and 30m sprint test. We had sessions with the athletes twice a week for 60 Minutes each time. Every workout started with warm-up, then continued with a 5-station circuit training and closed with stretching.

METHODS: Core muscular strength was significantly (p<0.001) improved by the exercise program, with the shortest time being 1.01 seconds, followed by 1.20 seconds, followed by the longest standing 3.15 seconds, after that 3.45 seconds. Static balancing capability was measured for both legs with FBT. Nonsignificant difference (p=0.16; p=0.09 were found on the right leg (pre: 2.33±1.50 and post: 1.88±1.32) and on the left (pre: 2.60±1.76; post: 1.80±1.37). In the case of dynamic balancing capability, significant (p<0.05) results were obtained for both leg in all 8 directions. Significant improvement (p<0.001) in endurance was also observed, they ran an average of 42.60 at the first time and 60.93 at the second time. There was no significant difference in athletes' speed (p=0.446), but the average of the first measurement was 4.77±0.26 seconds, while at the second measurement was 4.66±0.23 seconds.

CONCLUSIONS: Based on our results, we can say that our exercise program was effective and functional training can be used to strengthen all important stabilizing muscle groups.