When I see someone walking leisurely on a treadmill, drifting off to the side while watching ‘Ellen’ three screens down on the right, barely breaking a sweat or even breathing hard, I have to chuckle and roll my eyes when they say to themselves, “I’m working out; I’m in the ‘Fat Burning Zone.’ I don’t know any super-lean athletes that got that way by strolling for twenty minutes a day. Look, moving of any kind is better than not moving at all, but if your goal is to lose weight, wandering and window shopping the glass fronts of Afternoon Television Boulevard is not the way.
Every manufacturer of cardiovascular equipment is guilty of this bit of mis-information, as they all come equipped with a pre-formatted “fat-burning” program to make it easy for people to use. You must also remember, they don’t want to get sued if you keel over from a heart attack while using their product.
But what does “fat-burning” really mean. In technical terms your body uses two different systems of energy to run your body: aerobic and anaerobic. Aerobic is like when you go to the grocery store after you’ve just had Sunday brunch. When you’re full, it’s pretty easy to stick to what’s on your list and take your time going through the aisles. But now imagine you started your day with a 5K run and then skipped breakfast. When you hit the grocery, your brain and stomach begin screaming at you! Your pace through the store is manic and you’re grabbing whatever you can get your hands on that seems fast. Maybe there’s a box of cookies open in your cart while you’re throwing in veggies and fruit and probably a pizza. This is Anaerobic behavior.
Let’s explain it like this: aerobic means that the fuel your body is creating is coming mostly from fat storage. However, it also means that the body is going at a slow enough pace that there is time to go to the storage tank, gather fuel, break it down to a usable substance and fire the engine.
The closer you get to the anaerobic threshold means that the demands for fuel are greater, the internal pistons are firing harder and faster and burning through the fuel. So you’re body grabs anything it can get its hands on: fat, glycogen, protein, muscle, etc.
At the end of the day, weight loss is basic math: you have to take more calories out of the system than you put into it. Sure in the “fat burning zone” you are only using fat for your fuel source, but you also will likely only be burning about 100 calories in a half hour. Whereas, if you work in the higher end of your aerobic zone, just under your anaerobic threshold, you might not be burning all fat, but you will burn 3-4 x more calories in the same time. Plus, later in the day, your body must repair whatever it broke down to use as “emergency fuel.” So you get an additional “after burn” affect where your body uses fat to fuel the work of replacing whatever was used up during your workout. Plus, 100 Calories in a half hour might seem like a decent deficit to you, but consider that 1 banana or two Oreos are enough to replace that amount. Which is better burning off the caloric equivalent of a few mouthfuls or of an entire meal?
I am not suggesting you get on a treadmill and run until you collapse or fly off the back. But here are some signs that you’re in the true “fat-burning” zone: you begin to get winded, you break a sweat, you couldn’t “do” it all day and it begins to be hard to focus on anything but the task at hand. Losing weight isn’t easy, but you are not immune to the laws of science. By following good nutritional principles, proper portion sizes, 20-30 min/3-4 x week in the “true fat-burning zone” and some strength training. You will get there, absolutely steadily and certainly!