The benefits of high-intensity interval training (HIIT) elude many athletes.
For those of you that aren't familiar, high-intensity interval training is a workout divided into alternating periods of high intensity and low intensity. Some sources venture to say that interval training holds no specific benefits over normal cardiovascular exercise.
This idea, however, is incorrect. You see, a basic understanding of physics can help overcome some of these misguided notions thrust upon us.
The (incorrect) argument goes something like this: work is force times distance, so speed doesn't matter. The same argument would then proceed to ramble about average calories burned and work done. The problem here, however, is that another aspect of work is being ignored altogether.
Work factors into another realm called power. Power is defined as the amount of work done over an amount of time. What's the bottom line? The faster you do an amount of work, the more power you exert, and the more bodily benefits you reap in the process. What benefits might these be? One of the foremost is a state of exhaustion known as anaerobic exercise.
Anaerobic exercise, or exercise "without oxygen," is incredibly inefficient from an energy standpoint. This is why it is difficult to sprint for any extended period of time. However, in this case, inefficiency can actually be used to your advantage during a workout. If a body is working aerobically, it efficiently utilizes glucose as an energy source, netting much larger amounts – a maximum of around 38 – of an energy-producing molecule known as ATP.
Long story short, this type of exercise utilizes the sugar in your body as an energy source. Now, when most people run or bike or swim or bobsled for exercise, they aren't hoping to burn sugar. No, most people want to burn fat. This is where inefficiency comes in. If anaerobic exercise can't utilize glucose as efficiently, it is forced to turn to other energy-producing processes, processes that actually need to pull energy from elsewhere.
So where does all of this new energy come from? It comes from fat.
That's right. High-intensity interval training burns more fat than regular low intensity running.
This knowledge grants us control over an otherwise clumsy effort to burn fat. You see, although "high intensity" interval training may seem intimidating, it is important to note that what each person considers "high intensity" varies.
"High intensity" is relative, meaning there is no set level considered to be of any intensity. It all depends on your energy level at the moment. If by your last interval you're just barely pushing your tired body around the track, but you're still doing so anaerobically, it's still "high-intensity."
Naturally, a body working at high intensity will feel completely exhausted more quickly than one leisurely moving on a track, treadmill, elliptical or bike. So, high intensity training achieves desired results within a shorter workout period – benefiting the busy, health-conscious college student.
Granted anaerobic activity is not the only way to lose fat, it simply targets energy-packed fat which constitutes a more efficient fat-burning effort. The prospect of high intensity interval training should not make you feel intimidated, but rather pose as an option.
It can simply supplement a normal workout that may otherwise consist of a monotonous hour on a machine, or it can make up an entire workout. Anaerobic exercise will feel differently than aerobic exercise because the body is working in different ways.
Namely, you're going to be exhausted. This is a good thing.
In the end, exercise is about developing a lifestyle that makes you happy as well as healthy. Most people don't particularly enjoy interval training, but enjoy the results, so it can be a serious love/hate relationship. As stated before, it can be used to supplement workouts as well.
Next time you run, try pushing it to the max for a short stretch, even just once, just to feel what it is like.
Andrew Fleming is a junior in neuroscience. He can be reached email@example.com.