Mental imagery may help maintain muscle strength
Although the “power of belief” sits on top of a mountain of anecdotal evidence associating it with everything from better overall health to even sending cancer into remission, a relative few have dared to conduct any actual scientific studies on a topic as controversial as this. However, a Ohio University research team put the idea to the test, investigating muscle loss in participants whom were immobilized for extended periods of time. Surprisingly, the use of mental imagery seemed to reduce the amount of atrophy expected for their level of inactivity, prompting us to reexamine the role the nervous system plays in muscle strength.
The research team, from the Ohio Musculoskeletal and Neurological Institute (OMNI) at Ohio University, set out to test the ways the brain’s cortex influences strength and muscle development. Designing an experiment that measured changes in wrist (forearm muscle) strength in three groups of adults (two groups that wore casts and a healthy control group), the authors asked half of the 30 cast-wearing participants to perform regular imagery exercises, such as imagining that they were contracting and then relaxing their wrists for several seconds on and off. Published in the Journal of Neurophysiology, the study is one of the first to test the hypothesis that the nervous system and the cortex play a critical role in determining the rate of muscle atrophy.
The 14 members of the cast-group that practiced the mental imagery exercises were verbally guided, given instructions like “Begin imagining that you are pushing in as hard as you can with your left wrist,” followed by a classical conditioning exercise such as “Push, push, push…and stop (for five seconds), then start imagining that you are pushing in again as hard as you can, keep pushing, keep pushing…and stop (for another five seconds).” The exercise was repeated four times consecutively followed by a one minute break, totaling in 13 rounds per session five days a week.
By the end of the month-long test period, the cast-wearing group who had practiced the mental imagery exercises (half of the 30 participants) experienced atrophy just as the cast-wearing control group did. Remarkably, however, the group that performed mental imagery exercises lost 50 percent of their strength compared to the non-imagery group, showing a 24 percent loss of strength compared to the control’s 45 percent decrease.
“These findings suggest neurological mechanisms, most likely at the cortical level, contribute significantly to disuse-induced weakness, and that regular activation of the cortical regions via imagery attenuates weakness and VA by maintaining normal levels of inhibition,” said Brian C. Clark, Ph.D., lead author of the study.
Although the researchers’ findings need to be replicated before they can claim that definitive evidence is found, their results strongly suggest that cortical inhibition plays a critical role in voluntary muscle activation following periods of inactivity.
Muscle inhibition and the psychosomatic connection
The researchers believe the reason that the imagery was so effective lies in the nervous system’s influence on the skeletal muscle system. Voluntary muscle activation, the mind’s ability to fully activate muscles, was impaired the most in the non-imagery cast-wearing group, taking the longest to recover after the month-long test period as well. Cortical inhibition, or an atrophy of the neural networks responsible for maintaining the psychosomatic connection, seems to be attenuated by regular exercise of them (only requiring the thought to keep the sensorimotor system active, preventing the connections from being reprioritized).
The results of this study have massive ramifications for the application of imagery as a therapeutic intervention in the future. Being a provider of mental and behavioral health treatment, Sovereign Health understands the tremendous influence that the mind has on the body, utilizing imagery-centric forms of treatment such as mindfulness based forms of psychotherapy and narrative therapy. We are also constantly striving to improve our brain wellness programs in our treatment of addiction as well, using brain mapping to identify cognitive abnormalities and biofeedback to train it back to a healthy state.
Written by Chase Beckwith, Sovereign Health Group writer