You know that the best way to burn body fat is by doing cardio. That’s pretty much common knowledge. You probably know too that you need to be around 70% of your max heart rate to achieve the best fat loss results. Right? Maybe? Wrong. It used to be believed that the most efficient way to burn fat was by staying within this certain heart rate range known as the “fat burning zone”, but recently it has been determined that this isn’t really true, and I agree. In fact, I’ve never really been a big believer in this so called “fat burning zone” for one main reason; athletes. Take a look at a football player versus a cyclist or a sprinter versus a marathon runner. Notice the way each of them is built. The football player and sprinter are lean and muscular while the cyclist and marathon runner are generally skinny and have very low amounts of muscle mass. Why do you think this is? One word: training.
The training styles of a power athlete versus that of an endurance athlete are extremely different, which causes their bodies to adapt and respond differently. The training style of the endurance athlete is along the same principles of the “fat burning zone” workout which keeps you at a steady pace for a long period of time. While this may be great for burning body fat it is terrible for maintaining or building muscle. In fact, your body will actually start to lose muscle! This is why the marathoners look so skinny and have relatively no muscle on their bodies. The power athletes on the other hand use a training style known as HIIT, or High Intensity Interval Training.
HIIT is a great way to simultaneously stay lean and build muscle mass. Look again at the 100 meter sprinter. He or she is lean and muscular, which is a direct result of his or her training regimen. Not only do they do cardio, they keep up with a weight program as well. We can focus on that later though. HIIT involves short durations of high intensity activity, like sprinting. Usually a 1:2 ratio works out pretty well, but it may be a 1:3 or even 1:4 ratio depending on the duration of your work interval. Let’s say our work to rest ratio is 1:2 and we are doing sprints. We would sprint for a number of seconds, let’s say 10, then rest twice as long, 20 seconds, and then sprint again. Repeat this as many times as you can handle and then give yourself a break. After you have fully recovered repeat the exercise.
There are several benefits to doing HIIT rather than slow, long distance cardio. First is the anabolic effect. HIIT actually promotes muscle growth and the use of type-II, or fast-twitch muscle fibers which are bigger, stronger, more powerful and more metabolic than type-I muscle fibers, or slow-twitch fibers. Type-I fibers, your slow-twitch fibers, are built for endurance rather than strength and power. Therefore, they do not consume as much energy in as short of an amount of time as the type-II muscle fibers do. Again, this explains why a marathon runner looks skinny and frail while the 100 meter sprinter looks muscular and fit. However, the athlete that is composed of primarily type-II muscle fibers will not have the endurance that the mostly type-I fiber athlete will have.
Another benefit of HIIT is the EPOC effect. EPOC stands for excess post-exercise oxygen consumption. This simply means that your oxygen consumption levels post-workout will be elevated to a much higher level than if you were to do slow, long distance cardio. What does that mean? It means you will burn more calories post-workout. So not only are you burning calories during your workout, your post-workout caloric burn is now elevated, leading to greater amounts of fat loss.
The one setback to HIIT is that it is very intense and hard on your body. I do not advise doing this style of training every day, but working in with a regular weight routine will yield outstanding results. I would recommend following a routine of 3 days of weight training and 2-3 days of HIIT in order to allow your body a day or two to recover from the intense work during the week. Also, you cannot keep up this pace for a long time. Starting off you may only do a total of 20 minutes of intervals, if even that. You must build up your tolerance to this kind of training as your body will not be used to the intensity. After a week or two work up to 30 minutes. If your goal is an hour of cardio try breaking up your intervals into 5 minute sections. For example, start with a warm up, then 5 minutes of 10 second sprint 20 second rest intervals, followed by 5 minutes of recovery. Repeat this pattern for an hour if you can. It is extremely difficult and I really don’t recommend it, but hey, if you’re looking for a challenge there it is!
Overall, if you are looking for an increase in metabolism and fat loss without losing muscle, but actually promoting muscle gain, go with the intervals! Sure the long distance cardio may be the traditional way of doing things, but the results of interval training are right in front of us every time we watch football, 100 meter sprints, or any other sport requiring short, powerful bursts of energy. These athletes are muscular, strong and lean just like all of us want to be. The difference is the training.
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