The human body is a highly adaptive machine with a biological tendency towards laziness. This makes sense when you think about how we evolved and what survival required of us once upon a time. And while those days of chasing our dinner with a spear are long gone, our body is still genetically programmed to work in the most efficient manner possible.

For modern man that efficiency translates into an uphill battle to maintain a fit body. In other words, if you want to continue to see results in your exercise regime you must continually increase the intensity of your workouts. As your ability to perform increases, the amount of work and intensity needed to produce the same response will increase as well. What you lifted or ran last month won't be good enough this month. Your body gets used to a certain level of work and then gets comfortable, and you stop making progress, you plateau.

I’m sure you heard people lament about how they just can’t seem to lose weight even though they go to the gym all the time. These are the same people who you see on the elliptical machine going along at a leisurely pace and reading the latest fashion magazine. Or they are the ones in the weight room who use weights so light they can easily carry on a conversation during their sets. Does this sound familiar? Is this you?


Well, here’s a little fitness secret: it’s not supposed to be easy. If you can read and turn pages of a magazine while you do cardio or if the last rep of a weight lifting set is as easy as the first, you are not doing your body any good. Sure it’s better than sitting on the sofa eating cookies, but not much. To keep fit, you must continue to challenge your body. You have to fight the inherent laziness that lives in us all.

Studies have shown that high intensity cardio workouts help rev-up the metabolism by burning fat and calories from glycogen. As the body replenishes needed glycogen by subsequent meals, the glycogen will replenish your body's reserves instead of turning to fat. Low intensity workouts do not provide this benefit. This adds up to health benefits well beyond the workout session and means that calories are melting away after the workout and that adds up to maximum fat loss and a more toned appearance.

So now you understand the importance of increasing the intensity of your workouts, but how do you know if you’re really doing it? How does one quantify intensity? The two main ways are by measuring your heart rate and your level of perceived exertion.

Heart Rate

Your heart rate doesn't lie, it's not complicated and it's not subject to interpretation. If you're training at 80 percent of your maximum heart rate, that's intense, however if you are just 10 beats above your resting heart rate, you obviously need to pick up the pace.

To determine your maximum heart rate take 220 and subtract your age. For example if you are 20 years old then your maximum heart rate would be 200 beats per minute. Most heart rate monitors will calculate your maximum heart rate, fat burning rate, resting heart rate and more.

However, if you don't want to shell out the money for a heart rate monitor, then you can go the low-tech route and talk. If you can talk easily, you're not working hard enough. If you can't say more than a word without gasping, or you aren’t able to speak at all, slow down. You should be able to get out a few words before having to breathe, but not a long sentence. Not as accurate as the monitor, but it'll get you close.