In order to assess the intensity level during your workouts, most trainers use the Rate of Perceived Exertion Scale, aka the RPE scale.
The RPE scale is how hard you think you’re working, on a scale of 1-10. I also recently read, and want to steal, that one trainer calls it, "The Level of Suck." I cracked up.
(I can't recall where I read that, or I'd include proper credit. And learn from my mistake... do not search for "intensity" + "level of suck.")
ANYhoo.... Just as the doctor asks you to rate your pain on a scale of 1 to 10, I’m going to ask you to rate your level of exertion. This is my favorite way of measuring intensity. Why?
1) No two people have the exact same level of physical fitness.
Telling everyone in a group exercise class to do 15 reps isn't always best. 15 might be too many for one person, and not nearly enough for another. Using the RPE scale, however, and asking someone to work at a 7 allows each person to adapt to their own level.
If I am working at an 7, and you are working at an 7, even if the exercise variation or rep count we’re doing doesn’t match, we’re still pushing ourselves at a high intensity!
2) It’s a tool you can use anytime, anywhere.
It’s less scientific than heart rate monitoring, but trust me, I know when I’m working at a 4 and when I’m working at a 7. And you will too.
3) As you get stronger and your fitness improves, your rating adapts.
In the beginning, walking up a small hill might feel like a 7 or 8 to you on the RPE scale. But four months later, that might be your warm-up! And then, you’ll need to jog up that same hill to get to a 7 or 8 on the RPE scale.
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RPE SCALE
Level 1: You’re sitting down reading about RPE. Level of Suck: Low
Level 2: You’re getting up to prepare to exercise.
Level 3: You’re moving around warming up.
Level 4: You’re beginning to sweat but you feel fine and can effortlessly talk with your workout partner.
Level 5: You’re just past “easy” and you’re beginning to sweat more. You can still chat. Level of Suck: Starting to Suck
Level 6: You can still talk, but you’re slightly breathless
Level 7: You can blurt out a few words, but you’d rather not. Who knew you could sweat like this?
Level 8: If someone speaks to you, all you can do is grunt in reply and shake your head “NO.” Level of Suck: HIGH
Level 9: You think you might die. Level of Suck: &#^(%$
Level 10: ………[blergh]……………………
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THE BOTTOM LINE
When exercising, intensity matters.
Altering intensity can amplify the effects of your workout. You can push yourself by adding sets or reps, using heavier weights, moving faster, increasing your intervals, and resting less - so long as you can do those things with proper form.
And you can do light intensity exercises when you need active recovery days, maintenance work, or to increase your N.E.A.T.