Cardiac rehabilitation plaque: HIIT and strength training reduced plaques by 9 mm³ in 6 months.

Cardiac rehabilitation plaque — a topic that until recently was discussed cautiously. Statins demonstrably reduce plaque. Exercise is «beneficial,» «helpful,» «reduces risks.» A review of five controlled studies (217 participants, PLOS ONE, May 2026) changes this wording. Cardiac rehabilitation plaque regression now has a measurable outcome in mm³ based on intravascular ultrasound data.

What is cardiac rehabilitation plaque regression

Cardiac rehabilitation is a structured programme of physical activity for patients with cardiovascular diseases. It's not simply «move more,» but specific protocols with controlled intensity, frequency, and duration.

An atherosclerotic plaque is not static. It alternates between phases of growth, stabilisation and rupture. Regression specifically means: a decrease in PAV (percent atheroma volume) and TAV (total atheroma volume) — two standard IVUS parameters.

Not «the patient is feeling better.» Fewer mm³ of plaque in the measured segment of the artery. This is a solid clinical outcome upon which cardiologists base their decisions.

Cardiac rehabilitation plaque through HIIT: −9 mm³ in 6 months

In the first RCT (Vesterbekkmo et al.), patients with atherosclerotic heart disease underwent cardiac rehabilitation twice a week. Each session consisted of 4 intervals of 4 minutes at 85–95% of peak heart rate, with 3 minutes of recovery at moderate intensity in between. A 10-minute warm-up at the start and a 5-minute cool-down at the end.

Results after 6 months: PAV decreased from 49.5% to 48.3%, and TAV decreased by 9 mm³. In the control group, TAV increased by 3 mm³. The difference between the two trajectories was 12 mm³ over six months.

The effect of the cardiac rehabilitation plaque is comparable to data from statin studies. This isn't «might help» – it is a fixed regression, measured by the same standard as the effects of the most well-known drugs.

Cardiac rehabilitation plaque through aerobics and strength training

In the second study (Kurose et al.), cardiac rehabilitation combined aerobic exercise (30 min on a stationary bike or treadmill at anaerobic threshold, three times a week) and bodyweight strength exercises – press-ups, squats, abdominal exercises, 3 sets of 10–15 repetitions at a perceived exertion of 11–13 on the Borg scale.

In the cardiac rehabilitation group, PAV decreased by 4.3 mm³, and plaque area by 1.6 mm². In the control group, both indicators increased. Simultaneously, CRP fell from 0.427 to 0.063 mg/dl over 6 months. This is an almost sevenfold drop in the inflammation marker.

The dose makes the poison

A third RCT compared intensive cardiac rehabilitation (≥2 sessions per week + ≥9000 steps per day) with standard care (1 session per fortnight + ≥6000 steps).

Intensive group: PAV −8.9 mm³. Standard group: −4.5 mm³. Both showed regression, but the cardiac rehabilitation plaque effect scales with session frequency. Twice the effect for twice the frequency.

Three mechanisms of the effect

The first is nitric oxide and the endothelium. Regular exercise increases the activity of endothelial NO synthase, improves vasodilation and reduces oxidative stress. Less stress means less endothelial damage, meaning fewer places where LDL can deposit and oxidise.

The second is macrophage switching. Training promotes the transition from the inflammatory M1 phenotype to the «repair» M2 phenotype. M2 macrophages contribute to the transformation of non-calcified unstable plaque into a more stable calcified form.

The third is a systemic reduction in inflammation. A fall in CRP is the visible end of a chain involving IL-10, a reduction in visceral fat, decreased platelet activity, and thickening of the plaque's fibrous cap.

Honest disclaimer

All five studies had a common problem: patients were receiving statins and other lipid-lowering drugs concurrently. It is not entirely possible to separate the contribution of cardiac rehabilitation from that of pharmacotherapy using the available data.

This does not negate the results – the trajectories between the groups are different, both groups are on the same medication. However, «exercise resulted in -9 mm³ regardless of statins» is an incorrect formulation. The honest position is: cardiac rehabilitation has a synergistic effect with pharmacotherapy, it does not replace it.

The review authors state directly: RCTs are needed with a design that isolates the effect of exercise. It is likely that such pure RCTs will never exist for ethical reasons - it is not an option to leave a patient with ASCVD without statins for the sake of experimental purity.

Which of these is useful?

A cardiac rehabilitation plaque is not an auxiliary measure for «general well-being». It is a quantifiable tool for secondary prevention with IVUS data, previously considered a monopoly of pharmacology.

HIIT or aerobic strength training – both approaches have shown regression where the control group showed progression. The question is no longer «beneficial or not», but «what specific dose of cardiac rehabilitation is justified for a particular patient».

For me personally, this research closes an old question. When I've been training for years and heard from doctors, «exercise is good, of course,» now I have something to reply with: here's PAV, here's TAV, here's -9 mm³. Training isn't just «background» to treatment; it works within the same class of measurable tools as statins.

The more detailed explanation of how training affects the cardiovascular system is in Section for the active. If you're looking for somewhere to practise cardiac rehabilitation, there is Hall and venue database.

---

Sources

• Desandri DR, Aslani AO, Qhabibi FR, Nikoletou D. Exercise-based cardiac rehabilitation and atherosclerotic plaque regression in ASCVD. PLoS One. 2026;21(5):e0347557. DOI: 10.1371/journal.pone.0347557
• Vesterbekkmo EK et al. High-intensity interval training induces beneficial effects on coronary atheromatous plaques. Eur J Prev Cardiol. 2023;30(5):384–92.
• Kurose S et al. Effect of exercise-based cardiac rehabilitation on non-culprit mild coronary plaques. Heart Vessels. 2016;31(6):846–54.