Have you come across the idea that you should run more slowly to burn more fat?
… Or you might have seen reference to the “Fat Burning Zone”?
…Or have you even been told that running fast doesn’t help you lose weight?
There is a lot of misinformation around this topic in the media, on websites, and even on posters in gyms.
If you’re interested in losing or maintaining weight, treat the concept of the “Fat Burning Zone” with caution. There is a lot of misunderstanding of the science. Let’s dig into the issues…
“Fat Burning Zone” Truths and Myths
It’s correct to say that when you exercise at a lower intensity, you are drawing your fuel from fat reserves in the body. When you increase your intensity, particularly when you start working more anaerobically, your body starts to draw more on carbohydrate reserves.
But this is simply about the fuel your body is using. When we talk about fat or carbohydrate energy sources, the term “fat” is often misunderstood. It is not the same as “losing weight”.
If your focus is on losing weight, it doesn’t matter whether the fuel you burn during exercise comes from fat or not. What ACTUALLY matters is your balance of calories. Are you using more calories than you are consuming?
Remember, what’s important is the total amount of calories you burn, not the proportion that comes from fat. In fact, if you exercise at a lower intensity, you are burning fewer calories in the same session (exercising for the same period of time).
So… working in the so-called “fat burning zone” may even result in using fewer calories in your workout, and therefore be less effective for losing weight. Don’t be too distracted by the word “fat”!
What’s the Best Way to Exercise For Losing Weight?
If you want to lose weight, you need to use more calories when you exercise than you take in when you eat.
For weight loss, it’s a simple equation: “Calories in” must be lower than “calories out”.
Or if you want to maintain your weight, “calories in” need to be the same as “calories out”.
And yes, you’ve got it, if you want to gain weight, you need “calories in” to be higher than “calories out”.
Part of the problem for newer runners is that they often overcompensate for their run by eating more than they actually need. Very approximately, you are burning around 100 calories for each mile you run. If you run three miles then eat a cake, you may have consumed more calories than you’ve burned!
So runners who start thinking that running isn’t helping them, and they aren’t losing weight or perhaps are even gaining weight, may in fact do better by keeping a closer eye on what they are eating.
How Can You Understand Your Needs, and Track Your Progress?
The challenge is to understand your daily calorie requirement, which is different for each person.
You then need to understand how many calories you are consuming, and how many you are burning through exercise.
This sounds like a bit of a headache, doesn’t it?! How do you work out what you need, and keep track of your intake? Thankfully there are various tools you can use to help you.
My particular favourite is the “My Fitness Pal” app (www.myfitnesspal.com). Based on inputting your current and target weight, this will calculate your daily calorie intake. You can keep track of all the food you consume by scanning barcodes (stored in the massive database within My Fitness Pal), or by entering ingredients. Once you’ve gone through the process of entering your most common foods and meals once, you can easily select them again. You can also then log any exercise you do, and see your daily balance. It’s immediately easy to see whether you’ve eaten more or less than you’ve used.
It’s reassuring really when you start thinking of weight management as a matter of mathematics!