Lai, Kenric.

Active-isolated (AI = 11) stretching was compared to static stretching (SS = 8), proprioceptive neuromuscular facilitation stretching (PNF = 10), and a control group (C = 9) at improving hamstring flexibility. Pre- and post-assessments of flexibility were performed with a goniometer on the right leg. All subjects performed a warm-up on an ergometer; after which, subjects in the stretching groups performed mode-specific stretching of both hamstrings 4 days per week for 4 weeks. A significant increase was found in flexibility after training for all stretching groups (p < 0.05). However, there were no significant differences in flexibility between groups (ANOVA: p > 0.05). It is possible the small number of subjects may have contributed to this finding.