There are many ways to gauge exercise intensity. I’m going to discuss 3.
The most commonly employed method for the exerciser (even when they are unaware of doing it) is “perceived” exertion. That is, do you think you are working out hard. This method is used for both aerobic cardiovascular exercise and weight lifting exercise.
Since the vast majority of exercises have no idea what they are capable of, or even how to improve their capacity to train intensely, this method is often no better than a crude guess based on no facts.
For an experienced exerciser, this method can have varying degrees of validity; from somewhat valid to paramount validity, especially when partnered with the second method.
The 2nd method for determining intensity being used with increasing frequency is heart rate training using heart rate monitors (see my previous blog). These can be worn or built into machines like treadmills, stair climbers, ellipticals, etc. This technology’s aim is to take the guess-work out. A persons heart rate will always progressively increase in response to progressively increased activity. It’s the same science (to a lower level of intensity) that is used during a stress test. While commonly associated with cardiovascular and aerobic training, it can be used with weight lifting and other anaerobic activities, too.
The 3rd, and last method I’m going to describe is primarily used in conjunction with body building and other high intensity weight lifting exercises, but could also be adapted to other forms of anaerobic activity (sprints, plyometrics)as well.
Momentary muscular failure, known in weight lifting circles as the High Intensity Training Technique, describes the moment in an exercise set that you are literally unable to perform an additional rep. Very few people ever develop the conviction to achieve this result, and usually just stop when they hit a certain number of reps or decide that the set got hard enough.
For someone who has been working out consistently and hasn’t noticed much in the way of results in a while, this is the surest method to break thru a plateau. For someone trying to become as physically powerful, and/or develop the greatest amount of muscularity, as possible, they must eventually achieve this level of commitment. At this intensity, all other modes of determining intensity are of secondary importance or actually counterproductive. The only way to determine if you’re achieving this intensity level is to try another rep. If you succeed in completing it, you haven’t accomplished your goal, yet! At this level, success is achieved at the moment you fail!