Effects of an intermittent static stretching protocol: Flexibility gains and maintenance over time

Objectives: To determinate the duration of the effects caused by Intermittent Static Stretching (ISS) on muscle elongation. Background: Flexibility training is considered an essential physical quality in sport competition, injuries prevention and adapted physically activity. However, there is little information about the duration of the effects provoked by a stretching protocol on muscles-tendon unit, even if elongation exercises are very common in all physical activities. Methods: Eighteen fitness active participants aged 20-30 years were recruited for this study and casually assigned to an Experimental Group (EG) or a Control Group (CG). Participants were tested using the sit and reach test. EG used the sit and reach protocol also as experimental exercise. Test were taken for both groups at 3, 6, 9, 12, 15, 30, 45, 60, 60, 120 minutes, after 4, 24, 48, 72 hours and the end 7 days after the last stretching set (EG) or basal condition measurement (CG). Results: Friedman and Dunn’s Post Hoc tests were used for statistical analysis. Results showed in EG increasing in basal R.O.M. (p< 0,001, +21%). In addition, this result is maintained for 48 hours. In the same group statistically significant decrease of gained ROM was identified at 72 hours (p<0,001, -8%) and 7 days (p<0,001, 10%) after the last ISS set Instead, no significant differences were found in CG. Conclusion: The results of this study showed the duration of ISS stretching effects, giving the possibility to plan weekly the flexibility training during a microcycle.