Dr. William Hanney


Mental imagery (MI) has been shown to influence flexibility when used with stretching. Currently, little evidence supports the efficacy of MI as an independent tool to increase flexibility. Therefore, the purpose of this investigation was to assess if a guided MI protocol could influence subject range of motion (ROM) measures. Thirty individuals with no history of lower limb injuries underwent initial measures, random group assignment, and post- intervention measures.The imagery group followed a guided visualization of a hamstring stretch, and the control group remained still for the same amount of time. No significant group by time differences were found between the two groups for any of the recorded measures. Although statistical significance was not demonstrated, a post hoc power analysis showed a small effect size on the ANOVA test for knee extension. This study shows that an acute MI-only protocol may not positively influence ROM measures in the hamstring musculature. Future work should use familiarization periods to determine if a learning effect is related to the efficacy of an MI protocol to influence flexibility and validated imagery assessment methods. Future work should also utilize different musculature and stretches to determine if visualization has a uniform influence globally and if different stretch variations may be more efficacious in influencing flexibility.

About the Author

Juan Pablo Rodriguez is a graduate from the sport and exercise science program at UCF. Juan is an evidence-based educator, strength and conditioning coach, and researcher. Juan works with different populations of all ages from general individuals, older adults and athletes. Juan helps to empower these individuals with sustainable habits to get on the right track and change their lives.


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