A recent study at Copenhagen University Hospital recruited 32 people who were obese and did not exercise. Participants did either 12 weeks of weight training or cardiovascular exercise – which was cardio on an exercise bike – or no change in activity.
The resistance exercise training in this study was designed as a 45-minute interval type, medium load, high-repetition, time-based training. Participants performed three to five sets of 10 exercises and the sessions were supervised.
Each person had an MRI scan taken of their heart before and after the study to look at two types of heart tissue – epicardial fat and pericardial fat.
Epicardial adipose tissue is thought to protect the heart by metabolizing fat and therefore preventing buildup of plaque.
Less is known about the effect of pericardial fat mass on heart function. But the researchers said it is ‘exclusively associated with cardiovascular risk factors, coronary calcification, and incident of coronary heart disease’.
Both forms of exercise resulted in the reduction of epicardial adipose tissue when compared to no exercise – cardio by 32 per cent and weight training by 24 per cent.
But only weight training had an impact on pericardial adipose tissue, which was reduced by 31 per cent compared to no exercise.
Both forms of fat are recognized as causes of heart disease.
The researchers concluded that ‘Overall, our results suggest that resistance training may be superior to endurance training as resistance training reduced pericardial adipose tissue and improved fitness and strength, while endurance training only improved fitness’.
‘Nevertheless, both exercise modalities were associated with reduced epicardial adipose tissue, suggesting that people with specific training preferences or requirements can benefit from both training modalities.’
The resistance training program intervention alone was effective in reducing both fat depots of the heart.
A healthy diet can also reduce epicardial fat by 32 per cent, according to a 2012 study.
Therefore, a combination of exercise and dietary restriction would have the greatest effect on heart fat, the authors said.