Gains in range of ankle dorsiflexion using three popular stretching techniques

Among modern stretching techniques none has clearly been shown to be the most effective for increasing range of motion. The most common stretching method comparisons are between static stretching (SS) and one or more Proprioceptive Neuromuscular Facilitation (PNF) technique(s). The two most frequently implemented PNF techniques are: contract-relax (CR); and contract-relax-antagonist-contract (CRAC). Previous comparative investigations among stretching methods have primarily observed changes in straight-leg hip flexion as a result of lengthening the hamstrings, a two-joint muscle. The present study observed gains in range of motion among three stretching methods (SS, CR, CRAC) of a joint limited by a single joint muscle, the soleus. Twelve subjects performed each of the three methods on separate days. Significant differences were observed among all methods (p = .001). Further analysis revealed the CRAC method was superior to the CR method (p less than .01), and the CR method was superior to the SS method (p less than .01). Significant pre-post-treatment gains in range of motion were observed as a result of the CR and CRAC methods, but not the SS method. The results of this study support the findings of those previous investigations for two-joint muscles in which PNF techniques were more effective than static stretching for increasing range of motion. Also, a reciprocal activation (CRAC in the present study) was the most effective for increasing range of motion.