# Addition of high-intensity interval training to a moderate intensity continuous training cardiovascular rehabilitation program after ischemic cerebrovascular disease: A randomized controlled trial PMID: 36686521 Journal: Frontiers in Neurology Published: 2023-01-04 Authors: Lapointe T, Houle J, Sia YT, Payette M, Trudeau F ## Question Does adding progressive supervised HIIT to a MICT cardiovascular rehabilitation program improve cardiorespiratory fitness, cardiovascular risk factors, physical function, cognition, and depression/anxiety markers more than MICT alone or usual care after ischemic stroke or TIA? ## Summary This randomized trial compared a 6-month combined HIIT plus MICT program, a MICT-only program, and usual care in community-dwelling adults after ischemic stroke or TIA. Both exercise programs improved estimated VO2peak by about 3 ml/kg/min compared with control, and benefits partly persisted 6 months after intervention. Adding supervised HIIT to MICT was safe and acceptable but did not outperform MICT alone. ## Population - Community-dwelling adults after ischemic stroke or TIA, ambulatory for more than 10 minutes and not in formal rehabilitation. - Sample size: 52 - Age: Mean 69.2 years (SD 10.7) - Sex: 33 men and 19 women - Fitness level: Deconditioned clinical population; mean baseline estimated VO2peak 19.7 ml/kg/min. - Health status: Prior ischemic stroke or TIA; common cardiovascular comorbidities and risk factors. ## Methodology - Three-arm randomized controlled trial with 12-month follow-up - 6-month intervention plus 6-month post-intervention follow-up - University kinesiology clinic and home-based exercise in Trois-Rivieres, Quebec, Canada - Randomized and controlled study design. ## Protocol - HIIT + MICT combined program. - Modality: Supervised upright ergocycle HIIT plus home-based MICT. - Work intervals: 30 to 60 seconds at 95% PPO. - Recovery: 60 seconds passive initially, then active at 40% PPO after 1 month. - Sets or repetitions: Several bouts per session; exact count not stated in text. - Intensity: 95% PPO for HIIT work bouts; 40% PPO for active recovery, warm-up, and cool-down; home MICT RPE 4-6/10. - Session duration: 20 to 40 minutes, including 5-minute warm-up and 5-minute cool-down. - Frequency: 3 aerobic sessions per week, with supervised HIIT frequency decreasing from 3/week to 1/week across the program. - Program length: 6 months. - Progression: First week supervised MICT only; HIIT began week 2; active recovery added after 1 month; work bouts progressed from 30 to 60 seconds; intensity adjusted after 3-month GXT. - MICT-only program and usual-care control. - Modality: Supervised upright ergocycle MICT plus home-based moderate aerobic exercise; control usual care. - Work intervals: Continuous exercise. - Sets or repetitions: One supervised MICT session and two home MICT sessions weekly. - Intensity: Supervised MICT at 50% PPO; home MICT at perceived exertion 4-6/10. - Session duration: Supervised sessions progressed from 20 to 40 minutes with 5-minute warm-up and cool-down; home sessions 30 minutes, divisible into 10-minute bouts. - Frequency: 3 sessions per week for MICT; no added exercise for control. - Program length: 6 months plus T12 follow-up. - Progression: Supervised exercise time progressed from 20 to 40 minutes and was adjusted to tolerance. ## Outcomes ### Estimated VO2peak Status: improved Both HIIT + MICT and MICT increased estimated VO2peak by about 3 ml/kg/min at T6, with some persistence at T12, while control decreased. Group x Time interaction F = 9.222, df1 = 4, df2 = 72, p < 0.001; HIIT + MICT 18.9 to 21.9 to 20.6 ml/kg/min; MICT 21.1 to 24.1 to 22.5; control 19.3 to 18.7 to 18.0. ### Peak power output Status: improved Both exercise groups increased PPO at T6 and remained above baseline at T12, while control decreased. Group x Time interaction F = 10.522, df1 = 4, df2 = 72, p < 0.001; HIIT + MICT 83.3 to 105.3 to 96.0 W; MICT 99.2 to 119.2 to 108.3 W; control 80.0 to 76.7 to 72.5 W. ### HIIT + MICT superiority over MICT Status: no clear change The combined HIIT + MICT program did not show superiority over MICT alone; most interaction variance reflected exercise groups versus control. Authors reported 99.6% of VO2peak and 98.5% of PPO Group x Time interaction variance due to merged exercise groups versus control, leaving quasi-null interaction variance between exercise groups. ### Self-reported physical activity and anxiety/depression Status: improved Both exercise programs increased self-reported physical activity and decreased anxiety and depression markers compared with control patterns. Article reports comparable increases/decreases; detailed table values vary by outcome. ### Safety Status: improved No adverse events were registered during the exercise programs. 0 registered adverse events in exercise programs. ### Attendance Status: improved Supervised attendance was high in both exercise groups; home attendance was more variable. Supervised attendance 95% (79-100%) for HIIT + MICT and 93% (77-100%) for MICT; home attendance 78 +/- 23% and 82 +/- 18%; no between-group attendance difference, p > 0.05. ### Cardiovascular risk factors Status: no clear change Blood pressure, lipids, HbA1c, waist circumference, and body composition did not show consistent exercise-driven improvements. Authors note baseline values were generally in therapeutic targets and results did not support improvement in these factors. ## Practical Insights - In post-stroke/TIA rehabilitation, adding supervised HIIT to MICT may be safe and acceptable but should not be assumed superior to MICT alone. - Progressive HIIT introduction after an initial moderate week is a practical safety pattern for clinical populations. - Home moderate aerobic sessions can complement supervised clinical sessions, but self-reported home adherence may vary widely. - For clinical users, program choice may reasonably depend on patient preference, supervision access, and adherence rather than presumed HIIT superiority. ## Limitations - Voluntary sample may create selection bias - Dropouts excluded from acceptability analysis - Limited sample size for some outcomes - Home exercise was self-reported and guided by perceived exertion - The study did not directly compare pure HIIT with pure MICT - Exercise interventionist could not be blinded - Sample was heterogeneous for age, time since stroke, TIA inclusion, and comorbidities - No participants with major motor impairments ## Safety And Adherence - No adverse events were registered during exercise programs. - HIIT was performed under clinical supervision because of high-risk post-stroke/TIA status and ethical approval considerations. - Blood pressure and heart rate were monitored during supervised sessions with defined stop thresholds. ## Original Sources - [PubMed](https://pubmed.ncbi.nlm.nih.gov/36686521/) (pubmed) - [DOI](https://doi.org/10.3389/fneur.2022.963950) (doi) - [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9846748/) (full text) ## Agent Guidance Preserve the paper-level scope of this note. Do not generalize beyond the population, protocol, measured outcomes, and limitations above.