Impact of 24 Weeks of Resistance and Endurance Exercise on Glucose Tolerance in Persons with Multiple Sclerosis

Background: Recently, the authors reported an elevated prevalence of impaired glucose tolerance in individuals with multiple sclerosis (MS), compared with matched healthy controls, indicating metabolic defects that may increase comorbidity. MS also leads to a more inactive lifestyle, increasing the likelihood to develop fat accumulation, muscle wasting/weakness, and exercise intolerance. In other populations, these health complications can partly be reversed by physical exercise. Objective: The aim of this study was to determine the impact of a mild-tomoderate-Yintensity exercise program on glucose tolerance, ranging between normal and impaired, in persons with MS. Design: Persons with MS (mean expanded disability status scale, 3.3 +/- 0.2; mean age, 48 +/- 15 yrs) were randomized to an exercise group (n = 29) or a nonexercise control group (n = 15). Glucose tolerance, as well as muscle strength, exercise tolerance, and body composition to validate the applied exercise program, was determined in both groups at baseline and after 6, 12, and 24 wks of mild-to-moderate-intensity combined endurance and resistance training. Results: No effects on blood glucose and serum insulin were detected. However, 6 mos of exercise improved muscle strength, exercise tolerance, and lean tissue mass within the intervention group as compared with baseline. In the control group, no changes were detected. Conclusion: Twenty-four weeks of mild-to-moderate-intensity combined endurance and resistance training was not able to improve glycemic control in this cohort of persons with MS. Future research is warranted to investigate the influence of higher exercise intensities on glucose tolerance, in an attempt to remediate metabolic deficits and to decrease the prevalence of comorbidities in MS.