Acute effect of static and dynamic stretching exercise on sprint and flexibility of amateur soccer players

The main aim of the study was to examine the acute effects of static and dynamic stretching during warm-up on the sprinting speed of amateur soccer players. The secondary aim was to determine the acute effect of stretching on the lower extremities flexibility. Eighteen adult athletes participated in the study, randomly performing 3 distinct flexibility protocols on non-consecutive training sessions. The first protocol comprised of 10min of soccer warm-up exercises, flexibility and sprint assessment, followed by 5min of static stretching and sprints. The second protocol was akin to the first one, except for the static stretching exercises, which were substituted for calisthenics, performed in a limited range of motion (ROM). The third protocol was similar to the second, but calisthenics were performed in a full ROM. Stretches were held for 10’’ and were repeated once more. Passive ROM was measured during hip flexion, hip extension, hip abduction, knee flexion and ankle dorsiflexion in the right side of the body, with the use of a flexometer. The duration of the sprint was measured with photocells. Statistical analysis revealed that the static stretching protocol significantly reduced the sprint speed of soccer players (p<0.01) whereas the two dynamic protocols significantly improved sprint speed of participants (p<0.05 to p<0.01). On the other hand, static stretching and calisthenics, performed in a full ROM induced significant increases (p<0.001) in lower extremities joint flexibility of soccer players, whereas calisthenics exercises performed in limited ROM induced a significant increase (p<0.05) only on the knee dorsiflexion. The findings indicate that the type of stretching performed prior to exercise, affects sprint capacity and lower extremity flexibility.