High-Intensity Aerobic Lifelong Training--AF
Condition: Atrial Fibrillation
MeSH terms: Atrial Fibrillation
Study type: Interventional

Summary: 
      This study is a single-center RCT. Potential subjects with symptomatic non-permanent AF will
      be enrolled to determine the effect of sprint interval training (SIT) in comparison to
      moderate-intensity continuous training (MICT) and non-exercise control in reducing AF burden.
      The Investigators will enroll 60 patients during the first 12 months of the study. Baseline
      data collection will be conducted during the first month after enrollment. After baseline
      data collection, subjects will be randomized (1:1:1) to SIT vs. MICT vs. non-exercise
      controls. The exercise training will last for 3 months followed by final data collection
      which will be completed in 1 month.
    

Detailed description: 
      Atrial fibrillation (AF) is the most common heart rhythm abnormality in the general
      population. Current recommended methods to maintain sinus rhythm or reduce AF burden (% time
      a person is in AF) in patients with non-permanent AF are costly and ineffective. Hence, there
      is an urgent need to discover novel inexpensive strategies to reduce AF burden. It is
      well-established that regular aerobic exercise reduces cardiovascular morbidity and
      mortality; however, adherence to regular exercise is poor rendering it an ineffective public
      health strategy. Evidence is emerging to suggest that traditional moderate-intensity
      continuous training (MICT) and high-intensity interval training (HIIT) may be associated with
      lower AF burden. Compared with traditional MICT, HIIT is possibly more time-efficient; hence,
      it may promote adherence. Since lack of time is the most common reason for poor adherence to
      regular exercise, the time-efficiency of HIIT holds promise to be a "game-changer". However,
      many knowledge gaps remain. First, HIIT has never been compared directly with MICT in
      relation to AF burden; thus, whether HIIT is comparable or superior to MICT is unknown.
      Second, the time commitment required for a "conventional" HIIT program (120 mins/week) is not
      substantially less than the recommended MICT (150 mins/week); hence, it is doubtful that it
      can be a real "game-changer" in terms of promoting adherence. Third, HIIT performed using a
      cycle ergometer is a safer alternative to the treadmill in older adults, but has not been
      evaluated in patients with AF. Finally, mechanisms underlying the salutary benefits of
      exercise in relation to AF burden remain unknown. To address these knowledge gaps, the
      investigators will evaluate an innovative HIIT program-sprint interval training (SIT)-using a
      cycle ergometer that only requires 10 minutes per session and 30 minutes per week, in
      contrast to the "conventional" HIIT program that requires 40 minutes per session and 120
      minutes per week. In this pilot randomized controlled trial (RCT), the investigators will
      randomize 60 subjects with non-permanent AF (1:1:1) to SIT vs. MICT vs. no exercise control.
      At enrollment, these subjects will undergo heart rhythm monitoring by a non-invasive
      ambulatory heart rhythm monitor, V02 max testing, assessment of cardiac size and function by
      cardiac MRI, and assessment of AF symptom severity; these measures will be repeated at 3
      months.
    

Intervention name(s): High intensity interval training; Moderate intensity continuous training; No Exercise
Intervention type(s): Other; Other; Other
Intervention description(s): exercise by use of stationary cycles; exercise by use of stationary cycles; no exercise training will be given and no exercise will be added to subjects routine
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Exercise