Low-volume, high-intensity interval training in patients with CAD

Area of Science:

• Cardiovascular disease research
• Exercise physiology
• Rehabilitation medicine

Background:

• Isocaloric interval exercise training programs improve physiological indices in patients with coronary artery disease (CAD).
• Low-volume high-intensity interval exercise training (HIT) is effective in healthy individuals.
• The efficacy of HIT in cardiac rehabilitation is not well-established.

Purpose of the Study:

• To compare the effects of 12-week HIT versus higher-volume moderate-intensity endurance exercise (END) on brachial artery flow-mediated dilation (FMD) and cardiorespiratory fitness (VO2 peak) in patients with CAD.
• To determine if HIT is a viable alternative to traditional endurance exercise in cardiac rehabilitation.

Main Methods:

• Twenty-two patients with documented CAD were randomized into HIT (n=11) or END (n=11) groups.
• Both groups underwent two supervised exercise sessions per week for 12 weeks.
• END involved 30-50 minutes of cycling at 58% peak power output (PPO); HIT involved ten 1-minute intervals at 89% PPO with 1-minute active recovery at 10% PPO.

Main Results:

• Both END and HIT groups showed significant increases in relative flow-mediated dilation (FMD) post-training (P ≤ 0.001), with no significant differences between the groups.
• Relative VO2 peak significantly increased in both groups post-training (P < 0.001), with no significant differences observed between HIT and END.
• Improvements in FMD and VO2 peak were comparable between the HIT and END groups.

Conclusions:

• Low-volume high-intensity interval exercise training (HIT) is a viable alternative to traditional endurance exercise for cardiac rehabilitation.
• HIT elicits similar improvements in cardiorespiratory fitness and endothelial function (FMD) as endurance exercise in patients with CAD.
• HIT offers a more time-efficient prescription for cardiac rehabilitation compared to conventional endurance training.