Feasibility and impact of whole-body high-intensity interval training in patients with stable coronary artery disease: a randomised controlled trial
Question
Does 12 weeks of low-volume whole-body HIIT improve cardiorespiratory performance, physical performance, and quality of life in stable coronary artery disease patients, and is the rowing-based protocol feasible for this group?
Summary
This randomized controlled trial tested 12 weeks of supervised low-volume whole-body HIIT on rowing ergometers in patients with stable coronary artery disease. Compared with standard care, HIIT produced large improvements in VO2peak, maximal workload, ventilation, submaximal heart rate, body fat measures, and several quality-of-life domains, with high adherence but more dropouts and several non-fatal adverse or injury events in the HIIT group.
Methodology
- Adults with stable angiographically verified coronary artery disease, mostly older men, at least 12 months after revascularization or myocardial infarction diagnosis.
- 142 participants.
- Rowing ergometer.
- Work intervals: Short-duration exhaustive high-intensity intervals, no more than 2 minutes.
- Recovery: 1:1 work-to-rest ratio; exact recovery duration not specified in main text.
- Intensity: Individual target intensity set at 100% of average maximum workload from session 7 and adjusted after sessions 16 and 25; actual intervals averaged 138 +/- 46 W and 117% +/- 11% of 5-minute all-out power.
- Approximately 30 minutes total; 6-minute warm-up plus about 12 minutes active interval training and about 18 minutes active training time.
- 3 sessions per week.
- 12 weeks.
- Randomized controlled trial with supervised HIIT and standard-care arms
- VO2peak, Maximal workload, Submaximal and maximal heart-rate and ventilation measures, and Body composition were tracked.
Outcomes
VO2peak
HIIT increased absolute VO2peak by 197 mL/min and relative VO2peak by 2.5 mL/kg/min, while standard care showed no meaningful change.
Relative VO2peak: HIIT +2.5 mL/kg/min [2.1, 3.0] versus standard care +0.2 [-0.2, 0.6], group-time interaction P<0.001.
Maximal workload
Wmax improved more in HIIT than standard care.
HIIT +23 W [19, 27] versus standard care +3.7 W [0.1, 7.2], group-time interaction P<0.001.
Ventilation and submaximal heart rate
HIIT increased VEmax and reduced submaximal heart rate compared with standard care.
VEmax group-time interaction P<0.001; HRsubmax group-time interaction P<0.05.
Body composition
HIIT reduced body fat mass and percent fat, but body weight and skeletal muscle mass did not significantly differ by group-time interaction.
Fat mass group-time interaction P<0.05; percent fat P<0.001; body weight P=0.18; skeletal muscle mass P=0.20.
Quality of life
HIIT improved physical component summary and selected SF-36v2 domains related to physical health and vitality.
Physical functioning P=0.001, role physical P<0.05, general health P<0.001, vitality P=0.01, physical component summary P<0.001 for group-time interactions.
Older than 75 subgroup
In exploratory analysis, patients older than 75 years improved absolute and relative VO2peak with HIIT while standard care was unchanged.
Relative VO2peak +1.7 mL/kg/min [1.1, 2.4] in HIIT versus +0.1 [-0.5, 0.6] in standard care; P<0.001 for group-time interaction.
Safety and dropout
Adherence was high and feedback was positive, but HIIT had higher dropout and several non-fatal adverse events or training injuries.
Adherence 97% (86%-100%); dropout 23% HIIT versus 9% standard care, P=0.02; no fatal adverse events.
Insights
- Supervised low-volume rowing HIIT can improve VO2peak in stable CAD patients with high adherence.
- Complex whole-body modalities may require a familiarization block before high-intensity loading.
- Clinical HIIT feasibility should report both adherence and adverse-event/dropout burden.
- A 1:1 work-rest structure with intervals up to 2 minutes is a reusable programming pattern, but the exact repetition scheme was not available in the main text.
Limitations
- Sample was predominantly male, limiting sex generalizability.
- Medication and comorbidities may have influenced training response.
- Beta-blocker treatment in 65% of participants may have affected maximal and other heart-rate measures.
- Main text did not fully specify exact interval repetitions.
- Findings are for stable, screened CAD patients under supervision, not unsupervised high-risk users.
Safety
- One non-fatal severe adverse event was reported due to worsening angina.
- Two patients withdrew because of training-related moderate adverse events: lower back pain and knee pain.
- Three mild self-limiting events were reported: ankle pain, mild vertigo/hypotension, and palpitations.
- No fatal adverse events were reported.
- The first 6 sessions emphasized rowing familiarization and technique to reduce injury risk.