Short-term effects of tactile stimulation of facial skin on hamstring muscle flexibility in healthy young males.

BACKGROUND

Inhibition of the suboccipital muscle group is shown to increase the flexibility of hamstring muscles. Reversely, stretching of the hamstring muscles is shown to change the pressure pain thresholds over the masseter and upper trapezius muscles. There appears to be a functional link between the neuromuscular system of the head and neck, and lower extremities. The present study aimed to investigate the effect of tactile stimulation of facial skin on hamstring flexibility in healthy young males.

METHODS

A total of sixty-six participants participated in the study. Hamstring flexibility was measured by the sit and reach (SR) test in long sitting and the toe touch (TT) test in standing before and after two minutes of facial tactile stimulation in the experimental group (EG) and after rest in the control group (CG).

RESULTS

In both groups, significant (P<0.001) improvement was observed in both variables, i.e., SR (from 2.62 cm to -0.67 cm in EG and from 4.51 cm to 3.52 cm in CG) and TT (from 2.78 cm to -0.64 cm in EG and from 2.42 cm to 1.06 cm in CG). When both groups were compared, a significant (P=0.030) difference was observed between EG and CG in postintervention values of SR only. Greater improvement was observed in the SR test in EG.

CONCLUSIONS

Tactile stimulation of facial skin improved hamstring muscle flexibility. This indirect mode of increasing hamstring flexibility can be taken into consideration while managing individuals with hamstring muscle tightness.