Effects of acute and chronic low-volume high-intensity interval exercise on cardiovascular health in patients with coronary artery disease

The merits of low-volume high-intensity interval exercise (HIT) have been established in healthy populations; however, no studies have examined this exercise prescription in patients with coronary artery disease (CAD). The present thesis examined the acute and chronic effects of HIT in patients with CAD. The first study demonstrated transient improvements in brachial artery endothelial-dependent function, which was assessed using flow-mediated dilation (FMD) 60 min following a single bout of either HIT or moderate-intensity endurance exercise (END) in habitually active patients. The second study demonstrated no effects of training status on the acute endothelial responses to exercise; following 12-weeks of either HIT or END training. However, there was a significant reduction in endothelial-independent function immediately postexercise, at both pre- and post-training, which requires further examination. The third study demonstrated comparable increases in fitness and resting FMD following 12-weeks of END and HIT, lending support to the notion that favourable adaptations are obtainable with a smaller volume of exercise. Finally, the fourth study demonstrated no change in heart rate recovery following 12-weeks of END and HIT. However, pre-training heart rate recovery values reported by our sample were in a low risk range, which suggests training induced improvements may only be achievable in populations with attenuated pre-training values. The results of this thesis provide preliminary evidence that supports the use of HIT in patients with CAD. The findings of favourable transient and chronic improvements following HIT are notable, especially given that the HIT protocol involves less time and work than END, which was modelled after the current exercise prescription in cardiac rehabilitation. Further investigations are necessary, including the assessment of additional physiological indices; the feasibility and adherence to HIT; the inclusion of CAD populations with comorbidities, including heart failure and diabetes; as well as other forms of HIT training, including HIT combined with resistance training.

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Heart rate recovery and heart rate variability are unchanged in patients with coronary artery disease following 12 weeks of high-intensity interval and moderate-intensity endurance exercise training

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2012-0354 ◽

2013 ◽

Vol 38 (6) ◽

pp. 644-650 ◽

Cited By ~ 27

Author(s):

Katharine D. Currie ◽

Lee M. Rosen ◽

Philip J. Millar ◽

Robert S. McKelvie ◽

Maureen J. MacDonald

Keyword(s):

Coronary Artery Disease ◽

Heart Rate ◽

Heart Rate Variability ◽

Coronary Artery ◽

Endurance Exercise ◽

High Intensity ◽

Heart Rate Recovery ◽

Moderate Intensity ◽

Artery Disease ◽

High Intensity Interval

Decreased heart rate variability and attenuated heart rate recovery following exercise are associated with an increased risk of mortality in cardiac patients. This study investigated the effects of 12 weeks of moderate-intensity endurance exercise (END) and a novel low-volume high-intensity interval exercise protocol (HIT) on measures of heart rate recovery and heart rate variability in patients with coronary artery disease (CAD). Fourteen males with CAD participated in 12 weeks of END or HIT training, each consisting of 2 supervised exercise sessions per week. END consisted of 30–50 min of continuous cycling at 60% peak power output (PPO). HIT involved ten 1-min intervals at 88% PPO separated by 1-min intervals at 10% PPO. Heart rate recovery at 1 min and 2 min was measured before and after training (pre- and post-training, respectively) using a submaximal exercise bout. Resting time and spectral and nonlinear domain measures of heart rate variability were calculated. Following 12 weeks of END and HIT, there was no change in heart rate recovery at 1 min (END, 40 ± 12 beats·min−1 vs. 37 ± 19 beats·min−1; HIT, 31 ± 8 beats·min−1 vs. 35 ± 8 beats·min−1; p ≥ 0.05 for pre- vs. post-training) or 2 min (END, 44 ± 18 beats·min−1 vs. 43 ± 19 beats·min−1; HIT, 42 ± 10 beats·min−1 vs. 50 ± 6 beats·min−1; p ≥ 0.05 for pre- vs. post-training). All heart rate variability indices were unchanged following END and HIT training. In conclusion, neither END nor HIT exercise programs elicited training-induced improvements in cardiac autonomic function in patients with CAD. The absence of improvements with training may be attributed to the optimal medical management and normative pretraining state of our sample.

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Effects of resistance training combined with moderate-intensity endurance or low-volume high-intensity interval exercise on cardiovascular risk factors in patients with coronary artery disease

Journal of Science and Medicine in Sport ◽

10.1016/j.jsams.2014.09.013 ◽

2015 ◽

Vol 18 (6) ◽

pp. 637-642 ◽

Cited By ~ 30

Author(s):

Katharine D. Currie ◽

Kaitlyn J. Bailey ◽

Mary E. Jung ◽

Robert S. McKelvie ◽

Maureen J. MacDonald

Keyword(s):

Risk Factors ◽

Coronary Artery Disease ◽

Cardiovascular Risk ◽

Coronary Artery ◽

Resistance Training ◽

Moderate Intensity ◽

Interval Exercise ◽

Low Volume ◽

Artery Disease ◽

High Intensity Interval

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Simple heart rate and QT parameters during stress exercise testing to assess presence and severity of stable coronary artery disease

Future Cardiology ◽

10.2217/fca-2020-0163 ◽

2021 ◽

Author(s):

Murugaiyan Rajarajan ◽

Mugula Sudhakar Rao ◽

Padmakumar Ramachandran ◽

Ashwal A Jayaram

Keyword(s):

Coronary Artery Disease ◽

Heart Rate ◽

Coronary Artery ◽

Heart Rate Recovery ◽

Stable Coronary Artery Disease ◽

Peak Exercise ◽

P Value ◽

Characteristic Analysis ◽

Qt Variability ◽

Artery Disease

Aim: The relationship between QT prolongation and myocardial ischemia is well known, however not many studies have correlated corrected QT interval and heart rate recovery with the severity of coronary artery disease (CAD). Methods: This was a single-center, prospective, observational study which included 127 patients with CAD and 124 patients without CAD. Results: Corrected QT variability from peak to recovery correlated well with CAD with a p value of 0.03. Receiver operative characteristic analysis did not show any significant diagnostic accuracy with any heart rate or QT parameters for predicting the presence or severity of CAD. Conclusion: Coronary artery disease is predicted by reduced ability of the heart rate to rise from rest to peak exercise and reduced recovery of heart rate and corrected QT from peak exercise to recovery at 1 min.

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