Moderate levels of physical activity and fitness could be associated with a decreased risk of developing amyotrophic lateral sclerosis (ALS) later in life, as revealed by a recent study. This connection was observed specifically in male participants, with no clear link found in female participants.
ALS is a rare and progressive neurodegenerative disease that impacts nerve cells in the brain and spinal cord. Individuals with ALS experience a loss of muscle control, often leading to complete paralysis and eventually death, with an average life expectancy of two to five years post-diagnosis.
The study, led by Anders Myhre Vaage, MD, from Akershus University Hospital in Norway, examined 373,696 Norwegian individuals with an average age of 41 over a span of 27 years.
Among the participants, 504 individuals developed ALS, with male participants accounting for 59% of the cases.
Participants reported their physical activity levels from the past year into four categories: sedentary; four or more hours per week of walking or cycling; four or more hours per week of recreational sports or intense gardening; or regular engagement in strenuous training or sports competitions. To account for the limited number of participants in the highest activity level, the third and fourth categories were combined into a single high activity group.
Results showed that among male participants, those with the highest physical activity level had a 41% lower risk of ALS compared to those with the lowest activity level, after adjusting for other influencing factors like smoking and body mass index.
In addition to physical activity, researchers also considered resting heart rate as an indicator of fitness. Men with the lowest resting heart rate had a 32% reduced risk of ALS in comparison to those with higher rates.
“Our findings suggest that, particularly for men, engaging in moderate to high levels of physical activity and maintaining fitness does not elevate the risk of ALS but might actually offer protection against the disease,” said Myhre Vaage. “Further investigations into the relationship between ALS and exercise should account for gender differences and higher levels of physical activity seen in professional athletes.”
One limitation of the study was that participants completed the physical activity questionnaire only once during the study period, potentially not capturing the full spectrum of their exercise habits over the almost 30-year duration of the research.
