Background: There is continued controversy related to flexibility gains from different stretching protocols and within single protocols. Stretching methods include static, ballistic, dynamic, and proprioceptive neuromuscular facilitation (PNF). A combination of stretching methods may be an improved way to increase active knee range of motion (ROM). This study evaluated a single program formulated with static and ballistic components. Objective: To compare active knee ROM following stretching programs which either included combined static and ballistic stretching (CSBS) or static stretching (SS) alone. It was hypothesized that CSBS would show a greater increase in active knee ROM than SS. Setting: The pre- and post- measurements were performed in a laboratory. Subjects were randomly assigned to either treatment group or a non-stretching control group and given written instructions on how to perform their designated protocol at home. Subjects: Forty-three (33M, 10F) healthy collegiate aged participants (24.0 + 3.69 yrs, 176.21 + 10.0 cm, 78.15 + 12.93 kg) with no history of injury to the lower extremity or low back for the previous 6 months were eligible to participate in the study. Interventions: Two treatment groups either performed SS or CSBS for 30 seconds on each leg, twice a day for 2 weeks. All subjects but 3 provided both legs, and each leg was evaluated separately, providing 83 total measurements. Main Outcome Measures: A Johnson Digital Inclinometer was used to measure active knee extension. A mixed ANOVA with a Tukey post hoc test was used for statistical analysis. Results: There was no statistically significant difference in active knee ROM between groups at the pre-test, F(2,80)=1.062, p=.351, partial ƞ2=.026 (SS: 52.56 + 7.50º, CSBS: 49.84 + 8.91⁰, control: 49.39 + 10.09⁰). There was a statistically significant difference in active knee ROM between groups at the post-test, F(2,80)=29.034, p .05). There was homogeneity of covariance’s, as assessed by Box's test of equality of covariance matrices (p = .076). There was homogeneity of variances, as assessed by Levene's test of homogeneity of variance (p>.05). Conclusions: SS and CSBS are equally effective for improving active knee ROM. A trend indicating CSBS showing only slightly greater differences may be due to limited time allowed to master the CSBS method, with no supervision during stretching sessions.
Blackhurst NR, Peterson JC, Herzog VW, Zimmerman EP. A Comparison of Static Stretching Versus Combined Static and Ballistic Stretching in Active Knee Range of Motion. The Internet Journal of Allied Health Sciences and Practice. 2015 Oct 20;13(4), Article 11.