Look at the description or goal of many exercise programs, and you're guaranteed to see "fat burning" on the list. In fact, it's a widespread belief that body fat is a substance that we'd all be better off with less of in general — it affects how we think about our weight, our diet, and the kinds of workouts we choose to do.
While fat is an important component of our bodies for optimal health, too much of it is never a good thing. But more than that squishy layer of skin along, say, your inner thighs or lower abs, what exactly does it mean to burn fat? The answer lies, in part, in a little science lesson — but we promise it's not as intimidating as it sounds. This is what Matthew Watt, Professor of Physiology from Monash University's Lipid Metabolism Lab, had to say about it.
How Fat Cells Work in the Body
To understand how to reduce fat, we need to have an idea of how fat cells work. In scientific terms, fat cells are known as adipocytyes, and everyone is born with a set number of them in their bodies. However, over time, new cells have the ability to form from what's known as adipocyte precursor cells — stem cell-like cells that can become fat cells. Fat, as most of us know, is stored all around our bodies — under our skin and around various organs.
What Happens to Fat Cells When You Work Out
So what exactly happens when we "burn fat" through exercise? Despite what many may think, you can't actually get rid of fat cells permanently through working out. Instead, these fat cells either shrink or expand. During exercise, the contents of fat cells are released into the body and transported to where they are needed in the body for energy, like to be burned and used by your muscles. This is what causes the fat cells to shrink, because your body requires more energy than you're feeding it. In other words, the fat reserves function as energy sources.
How Excess Fat Cells Contribute to Weight Gain
On the flip side, when there's more energy input than output — when you're consuming more calories than needed — our bodies store this excess as fat reserves. This results in the expansion of our existing fat cells and our body realizing that we need to store more fat. This causes the production of new fat cells. The fundamental basis of weight gain and weight loss lies in this maintenance of energy balance.