Strength training enhances muscle activation and muscle strength, but neural adaptations to strength training remain unexplored in MS patients.
Marius S. Fimland • Jan Helgerud • Markus Gruber • Gunnar Leivseth • Jan Hoff
Multiple sclerosis (MS) is a disease affecting the central nervous system, leading to impaired muscle activation and lower limb strength. As a consequence, MS patients are neither able to fully activate muscles in the lower limbs nor to drive active motor units at high firing frequencies. Accordingly, the muscle strength of MS patients is 30–70% lower compared to healthy control subjects, stating that muscle weakness is a common symptom of MS.
Strength training enhances muscle activation and muscle strength, but neural adaptations to strength training remain unexplored in MS patients. The hypothesis was that maximal strength training (MST) using high loadsand few repetitions would improve central neural drive and thus strength capacity of MS patients.
14 MS patients staying at a national MS rehabilitation center were randomly assigned to a MST group or a control group. Both groups received ‘‘today’s treatment’’. In addition, the MST group trained 4 x 4 repetitions of one leg dynamic leg press and plantar flexion 5 days a weekfor 3 weeks. Neural adaptations of the soleus muscle were assessed by surface electromyography (EMG) activity.
In the MST group, maximal strength increased on average 20% and EMG activity increased by 40% compared to the control group. No change was apparent in the control group. MST group subjects were able to complete all training sessions. No adverse effects were reported.
Conclusion: This randomized study provides evidence that MST improve central neural drive to the leg muscles and strength capacity of MS patients, and thus reducing some of the neuromuscular symptoms in patients with mild and moderate disabilities linked to the disease.
Read the full study: https://pubmed.ncbi.nlm.nih.gov/20512584/