Reps In Reserve (RIR), Explained + How To Incorporate It In Your Training


When you are doing a strength training workout, it is important to know how hard you are working or the relative intensity of your effort.

Depending on your primary resistance training goals and fitness level, you will want to select a weight for each exercise that corresponds to a different relative intensity range.

Although there are a couple of different ways to determine how much weight you should be lifting, one of the most popular methods is to use reps in reserve.

But, what does reps in reserve mean? How do you use reps in reserve in strength training?

In this article, we will discuss the RIR meaning, what an RIR workout or RIR weightlifting entails, and how to use reps in reserve in weightlifting to maximize your gains in strength and hypertrophy.

We will cover the following: 

  • What Are Reps In Reserve?
  • How to Calculate Reps In Reserve 
  • What Are the Benefits of Reps In Reserve?
  • Reps In Reserve Chart for Strength Training

Let’s dive in! 

A bicep curl.

What Are Reps In Reserve?

If you are relatively new to strength training, you might hear other weightlifters in the gym use the terms RIR workout or RIR weightlifting. So, what is the RIR meaning?

RIR in strength training is an acronym that means reps in reserve.

RIR, or reps in reserve, is used in cases where you may not know your one-repetition maximum (1RM) for an exercise but still need a way to calculate how much weight you should be using.

In this way, a reps in reserve chart or calculating your RIR can be useful for programming your workouts properly based on your strength training goals either when you do not have a good estimate of your 1RM for the lift.

Essentially, reps in reserve is a method used in weightlifting to quantify the intensity of a strength training exercise by considering how many more reps you could theoretically perform before you have reached muscle failure or technical failure such that you can no longer perform the lift with proper form.

The remaining potential reps before your failure are your reps in reserve, or RIR.

Reps in reserve can be equated to money left in your wallet when you go shopping. You have potential maximum spending with cash, and your RIR is essentially quantifying the relative percentage of the money you have spent, given the total potential you could have spent.

Dumbbell bicep curl.

How to Calculate Reps In Reserve

So, how do you calculate RIR?

To calculate your RIR weightlifting, all you have to do is subtract the number of reps you actually perform for a given lift from the number of reps you could have possibly performed with proper form.

For example, if you are doing the barbell back squat and you complete your set with eight reps, but you could have potentially done 10 reps with correct form and technique if you had trained to failure, then your reps in reserve, or RIR, for the lift, is 2. 

This is because you could have done 2 more reps.

While calculating reps in reserve is certainly simple in theory, it can take some time to get used to how the scale works and accurately estimate your reps in reserve for an exercise.

Overhead press.

What Are the Benefits of Reps In Reserved?

As mentioned, the primary benefit of using the reps in reserve method in strength training is that it allows you to quantify the relative intensity of your workout set, which is particularly helpful when you do not know your one-rep max for the exercise.

However, there are additional RIR benefits as well, namely in the fact that the RIR scale is sliding and can adjust from day to day based on how you are feeling.

When you hit the gym for your weightlifting workout, you won’t necessarily feel your absolute best every single day.

One of the downsides of basing your loads for each exercise on your 1RM for the exercise is that, in most cases, your 1RM is calculated or estimated from a peak performance when you’re feeling your best.

While there is nothing inherently wrong with this, and you certainly want your 1RM to be your true max (which would require feeling your best), the reality is that there will be plenty of workouts or days in the gym when you are not feeling your best.

Dumbbell row.

Consequently, if you are calculating the weights for each exercise based on your peak performance when you are feeling your absolute best, you may be overtraining or overdoing it on days when your body is fatigued, your coordination or precision is poor, or you simply feel sore and low on energy.

This can potentially increase the risk of injury or overtraining and, more immediately, can be disheartening and frustrating when the lifts feel harder than they should.

In contrast, an RIR-based workout will automatically adjust to how you are feeling on that particular day with that particular exercise.

This means that even if you are not performing at maximum capacity or you feel like you are not firing on all cylinders, you can still have a safe, effective, and psychologically motivating workout that meets your needs and goals.

In this way, an RIR workout is scaled to your readiness to train, helping you still hit the desired intensity with the correct form and technique without overdoing it when your body is not fully recovered or at maximum capacity.

Bench press.

Additionally, doing an RIR workout vs. training to failure also has additional benefits. In other words, leaving something “in the tank” can be better than totally maxing out in your workout sets until muscle failure or technique failure is reached.

Although high-volume training is thought to increase muscle growth potential and support muscle hypertrophy. Studies have found that training to failure can lead to excessive muscle damage.

This will then increase your recovery time and may mean that you cannot hit your next workout as soon, reducing your training frequency, or you won’t be ready to perform fully at your peak potential.

As a result, your overall training volume and intensity will decrease, which can compromise your mass and strength gains. 

In fact, research indicates that training to failure may extend recovery time by as much as 24 to 48 hours relative to having some reps in reserve and stopping a set before muscle failure is reached.


Moreover, doing RIR weightlifting rather than training to failure can help protect against overtraining.

Unsurprisingly, studies have found that training to failure can result in the accumulation of fatigue over time, which can then increase the risk of overtraining.

Research even indicates that within a given workout, when you perform a set to muscle failure, rather than leaving some reps in reserve, your performance in subsequent sets may be compromised.

For these reasons, using the reps in reserve method of strength training is a great way to gauge workout intensity and help you achieve your strength and hypertrophy goals without overreaching and sabotaging your gains.

Reps In Reserve Chart for Strength Training

The following reps in reserve chart, or RIR chart, provides a recommended rep range and reps in reserve for each of the five phases of the NASM OPT Model, or Optimum Performance Training Model.

The Optimal Performance Model was developed by Dr. Mike Clark and is designed to help progress athletes through five distinct yet complementary training phases that help improve strength, hypertrophy, power, and muscular endurance.

Overhead press with dumbbells.

Here is a guideline for using RIR in your strength training program based on your training phase:

RIR Chart for Strength Training

Phase of Training Target Maximum RepetitionsRecommended RIR
Phase 1: Stabilization Endurance12-20 reps per setRIR 0-1
Phase 2: Strength Endurance8-12 reps per setRIR 0-1
Phase 3: Muscular Development6-12 reps per setRIR 0-4. Train to failure (RIR 0) only with the last set of an isolation exercise (like biceps curls). For multi-joint, compound exercises, aim for an RIR of 2-4 to prevent overdoing it
Phase 4: Maximal Strength1-5 reps per setTypically, aim for an RIR of 1-2, but occasionally, an RIR of 0 is doable for advanced weightlifters
Phase: 5 Power1-5 reps per set for strength and 8-10 reps per set for explosive powerRIR of 2-3 for strength and RIR of 4 for explosive power in order to maintain proper intensity and speed without risking injury

For more information about strength training programming, check out our complete guide to deloading here.

A person holding a barbell.
Photo of author
Amber Sayer is a Fitness, Nutrition, and Wellness Writer and Editor, as well as a NASM-Certified Nutrition Coach and UESCA-certified running, endurance nutrition, and triathlon coach. She holds two Masters Degrees—one in Exercise Science and one in Prosthetics and Orthotics. As a Certified Personal Trainer and running coach for 12 years, Amber enjoys staying active and helping others do so as well. In her free time, she likes running, cycling, cooking, and tackling any type of puzzle.

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