Abstract
This study aimed to determine whether increases in flexibility following a single
session predict increases in flexibility after a short-term stretching training program
involving static stretching (SS) or proprioceptive neuromuscular facilitation (PNF)
techniques. 70 adults (aged 18–30 years) of both sexes were randomly assigned to 2
groups: PNF (2 series of contract-relax stretching) and SS (static stretching for
1 min). Both stretching protocols were performed for 7 consecutive days. Active knee
extension was evaluated before and after the first session and one day after the end
of the intervention. Two-way ANOVA showed significant flexibility gains for both groups
and no difference between them. The changes in flexibility after the first intervention
session were strongly correlated with the changes after the training program in both
groups (PNF r=0.82, p=0.001; SS: r=0.82, p=0.001). Linear regression showed that the
increases in flexibility predicted the gains after both training programs (PNF: r2=0.67, p=0.001; SS: r2=0.61, p=0.005). In conclusion, the acute changes in flexibility after a single session
of PNF and SS predict the gains in flexibility after longer-term training programs.
Key words
muscle stretching exercises - range of motion - muscle - flexibility - stretching
