Heart disease is one of the leading causes of mortality around the world with obesity ranking as one of the highest risk factors of developing cardiovascular disease. The best way to help your heart health is to get the weight off from all areas of your body—but a study from last summer reminds us that it could be even more important to reduce the weight that surrounds the heart itself.
Fat & The Heart
When the body has too much fat tissue, it not only accumulates in the tissues of the body where we see it around the outside of the body, but also inside the spaces we can’t see surrounding our organs. In particular, the amount of fat that surrounds the actual heart itself is an area which needs special attention.
Not all fat surrounding the heart is problematic; in fact, one of the types of fat that surrounds the heart is protective. The fat tissue around the heart (called cardiac adipose) has an inner and outer layer. The layer of fat closest to the heart is called epicardial adipose, and its role is to protect the heart by helping the body metabolize fatty acids which keeps atherosclerotic plaques from forming. This is a cardioprotective mechanism of action, but it can have difficulty keeping up with the release of inflammatory fat cells as it grows bigger due to excess fat tissue accumulating in the body.
The outer layer is called the pericardial adipose tissue and is the single-most important measure of the risk of cardiovascular disease. You may be surprised to know that some of the most widely prescribed mediations to treat heart disease also target reducing the epicardial fat tissue. The outer pericardial fat tissue is harder to reduce; however, certain types of exercise can reduce both types of cardiac fat tissue.
When you make dietary changes and start watching fats and sodium on a heart-healthy diet, the epicardial fat tissue is the type of fat tissue affected. Following dietary restrictions can reduce that type of fat tissue by 32%, but it won’t change the other type of pericardial fat tissue.
How Lifting Weights Changed the Cardiac Fat Tissue
Last summer, the July issue in the Journal of American Medical Association Cardiology issue carried out a very detailed study on what types of exercise could reduce the pericardial fat deposits. Researchers investigated whether strength training was as beneficial to cardiac health as the touted aerobic “cardio” exercises like walking or running which go hand-in-hand with most recommendations for patients who are diagnosed with heart disease.
For 12 weeks, sedentary adults with abdominal obesity were put in an endurance and resistance exercise program of 3 45-minute sessions per week. They were divided into 5 groups: no exercise with a placebo, exercise and a placebo, no exercise plus a cardiac medication (tocilizumab), resistance exercise with a placebo, and exercise plus a cardiac medication (tocilizumab).
The endurance exercise was HIIT (high-intensive interval training) on a stationary bike while the resistance exercise was 3 to 5 reps of 10 exercises with medium weights.
What the Results Showed Us
Whether the participants did the resistance or endurance training program, the reduction of fat tissue in the inner layer (the epicardial adipose tissue) wasn’t different. Where things really showed a difference was in the pericardial fat tissue, which is where cardiovascular disease risk is most important.
Endurance training versus no exercise at all reduced pericardial fat tissue by about 15 g, but resistance training reduced the pericardial fat tissue by 34 g compared to the no exercise group. Simply put, resistance training was proven to reduce pericardial fat tissue while endurance training did not.
It’s still important to make sure to get regular aerobic activity, but this study shows that incorporating a weight-lifting routine for resistance training can help target a specific piece of the heart health puzzle. Using both types of exercise can give you a well-rounded and effective approach to reduce general fat tissue in the body while helping your heart where you need it the most.
Christensen RH, Wedell-Neergaard A, Lehrskov LL, et al. Effect of Aerobic and Resistance Exercise on Cardiac Adipose Tissues: Secondary Analyses From a Randomized Clinical Trial. JAMA Cardiol. 2019;4(8):778–787. doi:10.1001/jamacardio.2019.2074