Reps in Reserve and Heart Rate Training are two different ways to measure how hard you are working during exercise. Reps in Reserve, or RIR, is about how many more reps you could do before you can’t do another one with good form. For example, if you stop a set when you feel like you could do two more reps, that’s 2 RIR. This method is mostly used in strength training and helps you avoid going to complete failure on every set. It lets you train hard but stay fresh, so you can do more work over time and recover better.
Heart Rate Training, on the other hand, uses your heart rate to figure out how intense your workout is. This is common in cardio workouts like running, cycling, or HIIT. You can use a heart rate monitor to see if you are in the right zone for your goal. For example, if you want to build endurance, you might aim for 60-70% of your max heart rate. If you want to push hard, you might go for 80-90%. This method gives you real-time feedback and helps you stay in the right range for your fitness goal.
Reps in Reserve is more about how your muscles feel and how close you are to failure. It’s subjective, meaning it depends on your own feeling and experience. Heart Rate Training is more objective because it uses numbers from a device. Both methods have their place. RIR is great for lifting weights and building muscle, while heart rate is useful for cardio and improving heart health.
Some people use both together. For example, you might use RIR for your strength sets and check your heart rate during rest periods or cardio intervals. This gives you a fuller picture of your effort and helps you train smarter. RIR helps you avoid overtraining and injury by not pushing to failure every time. Heart rate helps you make sure you are working hard enough to get the benefits you want.
Sources
https://rippedbody.com/rpe/
https://pmc.ncbi.nlm.nih.gov/articles/PMC12593510/
https://fitnessrec.com/articles/exercise-intensity-metrics-for-athletes-train-smarter-and-maximize-results
https://www.empower.physio/blog-all/rpe-vs-rir-1
https://www.elevaterope.com/blogs/articles/rate-of-perceived-exertion
https://betterlifefitness.net/rpe-to-1rm-calculator/
https://betterme.world/articles/building-a-workout-plan/amp/
https://www.mensjournal.com/health-fitness/what-is-escalating-density-training
