Weakness, Fatigue Can Signal Underlying Rheumatologic Disease

A novel area of weakness research focuses not on muscle, but on the brain. A recent study tested the hypothesis that the cerebral cortex is a critical determinant of muscle strength and weakness and that a high level of corticospinal inhibition is an important neurophysiological factor regulating force generation.⁹

A group of healthy individuals underwent four weeks of wrist–hand immobilization to induce weakness. Another group also underwent four weeks of immobilization, but they were trained in mindfulness, performing mental imagery exercises of strong muscle contractions five days per week. Mental imagery has been shown to activate several cortical areas that are involved with actual motor behaviors, and in this study, this activity attenuated the loss of strength by half.

Mind over muscle? I wish it were true.

Simon M. Helfgott, MD, is associate professor of medicine in the Division of Rheumatology, Immunology and Allergy at Harvard Medical School in Boston.

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