RESUMO
AIM: Forward flexibility of the trunk (FFT) is used as an indicator of vertebral function and assessed using the sit-and-reach and fingertip-ground tests. METHODS: FFT was investigated in adolescents and comparisons were made among genders, sitting and standing positions, and low and high speed; 102 males and females (16 to 20 years of age) participated in the study. RESULTS: The position of the body and gender factor had no influence over the flexibility assessment. When executed slowly, the values obtained in the test were significantly lower; 60% of the participants were unable to reach their feet in the slow form and 50% were unable to reach their feet in the fast form. Thus, the assessment of vertebral function in adolescents should not use the ability to reach their feet as a criterion of normality. The fingertip-ground and sit-and-reach tests proved to be equally adequate. Greater height and length of limbs are associated to lower FFT values. Greater height and lower trunk-head height explain the lesser FFT in women; greater length of the lower limbs and lesser arm span explain the results for men. CONCLUSIONS: Reaching the feet in either the standing or sitting position is a criterion that excludes approximately 50% of adolescents from the normality of vertebral function, whereas reaching 12 cm above the ground is achieved by 90% of the population. Therefore, the criteria for assessing FFT in adolescents need to be reviewed.
