Extensive exercise is not harmful in amyotrophic lateral sclerosis

Area of Science:

• Neuroscience
• Exercise Physiology
• Genetics

Background:

• Amyotrophic lateral sclerosis (ALS) is a motor neurone disease with debated links to physical activity.
• Pathophysiological hypotheses include excitotoxicity, oxidative stress, and calcium dysregulation.
• Vigorous exercise could potentially exacerbate these factors by increasing motor neurone firing rates.

Purpose of the Study:

• To investigate whether lifetime vigorous exercise promotes or hinders motor neurone degeneration in a mouse model of ALS.
• To determine if increased motor neurone activity due to exercise impacts ALS progression.

Main Methods:

• A transgenic mouse model overexpressing mutant human Cu/Zn superoxide dismutase-1 (SOD-1) was used.
• Mice were divided into an active group (10 h daily vigorous exercise) and a sedentary group (slow speed exercise).
• Disease onset and progression were monitored using grip strength, stride length, and tight rope tests.

Main Results:

• No significant differences were observed in disease onset or progression between the active and sedentary SOD-1 mouse groups.
• The exercise group showed a non-significant trend towards improved survival compared to sedentary and control groups.
• Lifetime vigorous exercise did not accelerate motor degeneration in this SOD-1 ALS model.

Conclusions:

• Vigorous, lifetime physical activity does not promote the onset or progression of motor neurone degeneration in SOD-1-mediated ALS.
• The findings suggest that increased neuronal activity and calcium turnover from exercise do not negatively impact the pathophysiology of this ALS model.
• This study provides evidence against exercise exacerbating ALS in this specific genetic context.