Rating of Perceived Exertion – Using a scale (1-10) to gauge how hard you perceive to be working.

As a trainer and strength coach, knowing how hard people think they’re working is vital feedback.

The RPE scale will rate from 1-10, with 1 being “this is no work at all” (pictured above) to 10 being “failure/that was extremely hard and I couldn’t do anymore.”

Another way to think about the RPE scale is by relating that number to the number of reps you left “in the tank”, or Reps In Reserve (RIR). For example, if I prescribed someone an intensity of a 7-8 RPE, I would want them to stop the set when they feel they could only do 2-3 more reps (10–8 = 2; 10–7 = 3), hence they left 2-3 reps in the tank.

Intensity should be a main focus of your attention while resistance training to ensure you’re doing it safely, you don’t develop chronic/acute injuries, and so your soreness is manageable – so you actually want to get back in the weight room regularly.

For beginners, aim for an RPE of 4-6 for the first few weeks of your exercise program. Once your soreness becomes less significant, you can move upwards in small increments on the RPE scale approximately a week at a time. Once you become more experienced and know how your body will react to certain intensities, it becomes easier to understand the RPE scale and you can use it within your own programming to determine how hard you should work.

If you were accustomed to weight lifting for several months, got past the initial “soreness” stage, and were getting ready to work on building some muscle and increasing strength, programming your own intensity (periodizing intensity based on RPE) instead of just using sets/reps may look like this:

Weeks 1-2: 3×12, RPE of 4-5 (easy lifting, focus on technique; very light soreness)

Weeks 3-4: 3×10, RPE of 5-6 (add small amount of weight; mild soreness)

Week 5: 3×10, RPE of 6-7 (add small amount of weight; same mild soreness)

Week 6: 3×8, RPE of 6-7 (add small amount of weight; mild soreness)

Week 7: 3×8, RPE of 7-8 (add small amount of weight; moderate soreness)

Week 8: 3×6, RPE of 7-8 (add small amount of weight; moderate soreness)

Week 9: 2×12, RPE of 5-6 (easy lifting, focus on technique; no soreness)

Week 10-11: 3×6, RPE of 7-8 (replicate Week 8 loads, adjust based on soreness; mild soreness)

Week 12-13: 3×6, RPE of 8-9 (add small amount of weight; moderate soreness)

Week 9 in the above example may seem out of place, but it’s a very necessary piece of the periodization puzzle. It’s essentially an “easy” week with the purpose of giving your mind and your body a break before continuing again and increasing intensity. If you’ve been training consistently but seem to be getting bored, end up in a plateau, or feel an injury coming on, take a week off (like Week 9, or just completely off from lifting) and you should come back far more prepared for the increase in intensity.

For another simple example, if you’re aiming for an RPE of 7-8 and doing a set of 10, reps 8, 9, and 10 should be quite tiresome and maybe even cause some burning in your muscles, but not so hard that your form starts to go to crap or you fail and drop the weight. Lifting to failure on every set is not necessary, nor is it enjoyable for most people. If you finish a set and think to yourself, okay, I feel like I’m at about an 8/10 and your form was still solid, then you’re right where you need to be.

Zourdos, Michael C., et al. “Novel Resistance Training–Specific Rating of Perceived Exertion Scale Measuring Repetitions in Reserve.”The Journal of Strength & Conditioning Research 1 (2016): 267-275.