Efficacy Of A Semi-supervised Exercise Training Program For Individuals With Postural Orthostatic Tachycardia Syndrome

Abstract

Healthcare guided in person exercise training is only offered to those with cardiac or pulmonary disease. Physical therapy, exercise consultations or recommendation from primary provider to exercise 150 minutes/week is the standard of care (SOC) for providing exercise guidance to all patients. This will be sufficient for some, however, the majority will not be successful in implementing this for multiple reasons: unsure where to start, hesitation about starting without supervision so they remain inactive or do not train at the necessary intensity and/or need more accountability as they start to develop the habit. PURPOSE: Assess the efficacy of a semi-supervised exercise training (ET) program on adherence, achieving the target heart rate zone (THZ) during training, and improving exercise tolerance and symptoms in individuals with postural orthostatic tachycardia syndrome. METHODS: Subjects were randomized to either the ET or SOC groups (n: 14 vs. 13; age: 31 ± 12 vs. 37 ± 11 yrs.; BMI: 24.4 ± 3.7 vs. 26.2 ± 5.8 kg/m2; VO2PEAK: 62 ± 16 vs. 70 ± 13% predicted, ET vs. SOC respectively, p > 0.05). A 10-minute stand test and maximal exercise test were performed at baseline and following 12-weeks. The ET group received an exercise consultation and 8 supervised in-person or virtual exercise sessions. All activity was tracked using a chest strap heart rate monitor and mobile app. RESULTS: The ET group were more likely to complete >2 sessions/week and the study recommended 3 sessions/week (>2/wk: 9 ± 3 vs. 5 ± 4 wks; 3/wk: 5 ± 3 vs. 2 ± 2/wks, p < 0.05). The ET group tended to have a higher average heart rate (HR) and were more likely to train in the THZ when exercising than the SOC group (HR: 125 ± 8 vs. 105 ± 37 bpm; THZ: 57 vs. 30% of participants, p > 0.05). The ET group showed greater increases in or long tolerance for their peak workload, were more often to have a delayed symptom onset with exercise, and less of a change in heart rate upon standing than the SOC group (ΔWorkload: 19 ± 17 vs. 0 ± 10 watts; Wtime: 63 ± 29 vs. 22 ± 30s; onset: 80 vs. 30%; ΔHR: -9 ± 15 vs. 4 ± 15 bpm, p < 0.05). CONCLUSION: Providing minimal supervision resulted in better improvements in exercise tolerance and symptoms than receiving an exercise recommendation/guidance with no supervision. Improved efficacy is likely due to increased likelihood of exercise being performed at the correct dose.