Have you ever wondered why two people can eat similar meals, yet one seems to gain weight much more easily?
While diet and physical activity are major contributors, there's another fascinating piece of the puzzle happening deep inside your muscles. It involves an enzyme called lipoprotein lipase, or LPL.
Think of LPL as a gatekeeper that sits on the walls of your blood vessels, particularly around muscle and fat tissue. Its job is to capture fat (triglycerides) circulating in the bloodstream and decide where that fat goes.
If LPL is highly active in your muscles, more fat is pulled out of the bloodstream and used as fuel. This means your muscles become more efficient at burning fat for energy, helping preserve a healthy body composition.
On the other hand, if muscle LPL activity is lower, less fat is directed into muscle for burning. Instead, more of that fat is available to be stored in fat tissue. Over time, this may make it easier to gain body fat, even when calorie intake isn't dramatically different.
This helps explain why some people naturally appear to "burn off" fat more efficiently than others.
A landmark study published in the American Journal of Physiology investigated this exact relationship. Researchers found that individuals with higher skeletal muscle LPL activity burned significantly more fat over a 24-hour period. In contrast, those with lower muscle LPL activity relied less on fat as a fuel source and were more likely to store it.
The encouraging news is that LPL activity isn't fixed for life.
Regular physical activity, particularly resistance training, can increase LPL activity within skeletal muscle. As muscle becomes more metabolically active, it becomes better at taking up and using fat for energy rather than allowing it to accumulate in fat stores.
Building and maintaining muscle therefore provides benefits well beyond strength. Muscle is one of the body's most important metabolic organs. The healthier and more active your muscles are, the better equipped your body is to regulate blood sugar, improve insulin sensitivity and utilise fat as fuel.
At AstonRx, we often remind our members that fat loss is about much more than simply eating less. It's about creating a body that works more efficiently. Supporting muscle health through adequate protein intake, regular resistance exercise, quality sleep and metabolic health can help improve your body's natural ability to burn fat.
The bottom line? Some people may be genetically predisposed to store fat more easily, but lifestyle still has a powerful influence. By building healthier, more metabolically active muscle, you can shift your body towards burning more fat and storing less.
