Introduction:
Exercise is important in the management of cardiovascular disease through its role in creating a negative energy balance that is conducive to weight loss. However exercise may lead to less than expected weight loss if compensation occurs through increased energy intake. On the contrary, exercise may also reduce energy intake through improved appetite regulation, which may be intensity-dependent. Our aim was to describe the change in energy intake resulting from a cardiac rehabilitation program involving high intensity interval training (HIIT) or moderate intensity continuous training (MICT).
Methods:
38 participants (30 male, 8 female) with coronary artery disease (mean age 65.8 ± 5.9 years and body mass index of 28.0 ± 4.2 kg/m2) were randomised to 4-weeks of either isocaloric HIIT or MICT, training 3 times per week. Estimated energy expenditure was ~1MJ per session (3MJ per week). Both groups received standard cardiac rehabilitation nutrition education. Telephone interviews were utilised to conduct 24-hour diet recalls on two days at baseline and 2 days after the 4-week training period. Manual and automated (ASA24) recall methods were employed.
Results:
A significant main effect of time was evident for daily energy intake (mean difference -656 ± 288kJ; 95% CI: -72 to -1240; p=0.029) when groups were combined. There was also a significant reduction in total carbohydrate (p=0.017) and fat intake (p=0.034) with time. There was no intervention effect between MICT and HIIT (p = 0.150). No effect on bodyweight was found for intervention (p=0.381) or time (mean difference 0.22 ± 0.21kg; 95% CI: -0.20 to 0.64; p = 0.304) when groups were combined.
Conclusion:
Our results suggest that low volume exercise training does not result in compensation through increased energy intake in patients undertaking a 4-week cardiac rehabilitation program. Additionally exercise intensity did not influence the change in energy intake.