Exercise Dose Associated With Military Service: Implications for the Clinical Management of Inherited Risk for Arrhythmogenic Right Ventricular Cardiomyopathy

Abstract

Introduction High levels of aerobic exercise in individuals who have a gene mutation associated with arrhythmogenic right ventricular cardiomyopathy (ARVC) are associated with clinical disease progression. Guidelines consequently restrict patients from competitive athletics. However, there is minimal literature to guide the safe dosing of physical activity outside of the setting of competitive athletics. Patients may be physically active pursuant to a variety of careers, including military service. This study aimed to define a therapeutic window for exercise for ARVC gene-positive individuals that are compatible with continuing military service and general health while maintaining a level of exercise below that which risks disease progression. Materials and Methods Using standard metabolic equations, we calculated the minimum VO2 max (amount of oxygen utilized at peak exercise capacity) required to pass the physical fitness tests for each branch. We then developed a sample exercise prescription to maintain this level of fitness. We compared the prescribed exercise load with the physical activity levels associated with non-inferior clinical outcomes in ARVC gene-positive individuals. Additionally, we determined the physical activity exposure sustained by service members based on self-report data and compared these values with the upper limit of safe exercise exposure. Results Based on a review of the currently available literature, aerobic exercise exposure less than 700 to 1,100 MET-hours/year (metabolic equivalent-hours per year) is not associated with inferior clinical outcomes for gene-positive individuals. A military service member needs 600 to 700 MET-hours/year to minimally pass the physical fitness test. However, many military members are exercising in excess of this minimum, with typical exposures between 900 and 2,400 MET-hours/year. Conclusions A therapeutic window of aerobic exercise may exist for ARVC gene-positive individuals which would allow continuation of military service while maintaining levels of exercise restriction associated with non-inferior clinical outcomes.

Physical exercise and arrhythmogenic right ventricular cardiomyopathy/dysplasia: An overview

“…The Medical Subject Headings (MeSH) terms used and combined were “Arrhythmogenic Right Ventricular Dysplasia” [Mesh] AND “Exercise” [Mesh], which resulted in 72 records. Seven animal or preclinical[ 15 16 17 18 19 20 21 ] and 18 clinical studies[ 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 ] were selected and discussed. [ Table 1 ] presents the definitions of terms used in the identified studies.…”

“…[ Table 1 ] presents the definitions of terms used in the identified studies. [ 22 23 25 26 27 28 29 30 32 33 36 ]…”

“…As reported in the literature, 700–1100 MET-h/year was not associated with inferior clinical outcomes, the study found that a member of the military service needs 600–700 MET-h/year for passing the physical fitness test. [ 30 ]…”

Arrhythmogenic Right Ventricular Cardiomyopathy - what do we know? A review of current knowledge state

“…Another study by Segre et al. [20] reported that activity below 700-1100 MET-hours/year is not associated with poor clinical outcomes for gene-positive individuals. Those studies show that low to moderate levels of physical activity may not be detrimental to patient's health and prognosis and they should not be completely deprived of the benefits of exercise.…”