That's Fit

One of the most amazing parts about exercising, that also happens to be one of the worst parts, is that your body quickly adapts to the effort placed upon it. For example, if today you are only able to walk one mile, you will likely be able to walk more than that distance a month from now if you follow a steady walking regimen. The good news is that you're becoming fitter, the bad news is that you are now required to exercise harder in order to become fitter still.

People that exercise for several months sometimes find that their results plateau. They have reached a certain level of fitness, but for some reason can't seem to break past that sticking point. This is probably due to two reasons: 1) This person has probably not changed their workout in quite some time, which will always lead to a plateau, and 2) They may not be exerting themselves as much as they should be. With regard to that latter, it may not always be easy to determine if you're trying hard enough. That's why knowing the following intensity formula may help.

After each set of an exercise, take note of how hard you think you worked on a scale from1 to 10 (1 means that you still have boundless energy left and 10 means that you feel ready to collapse onto the floor). Then, figure out what percentage of your maximum heart rate (MHR is equal to 220 - your age) you reached for the majority of your workout. If you're not hovering at around 60 to 85 percent of your MHR for most of your workout (which is basically around the 7 mark on your intensity scale), then it may be time to pick up the pace.