Stretching exercise volume for flexibility enhancement in secondary school children

The study aim was to establish the threshold of stretching volume for flexibility enhancement during physical education lessons in secondary school children.

Subjects were 239 tenth grade children randomly assigned to four groups (boys 107, girls 132, mean age 15.1 ± 0.4). Children involved in after-school sports were not included in the study. Physical education lessons were performed twice a week for 45 minutes in duration. The intervention lasted for five weeks comprising 10 physical education lessons. Flexibility was determined from sit and reach test before and after intervention. Subjects in group 1 performed standard "sit and reach" test of four trials in every physical education lesson; in group 2 received one stretching exercise of four repetitions; group 3 received four stretching exercises of four repetitions; in group 4 no stretching was performed.

Flexibility improvement in group 3 were the greatest (21.6%; P<0.05), smaller in group 2 (12.6%, P<0.05) and smallest in 1 group (5.1%, P<0.05), while control group changes were insignificant (1.7%, P>0.05).

The main finding was that single flexibility test performed twice a week for five weeks was sufficient stimulus to increase range of motion in secondary school children. Stretching exercises provides exceptional prospects to achieve youths' improvement since schoolchildren are very sensitive to flexibility training.