How to Find Your One-Rep Max

Get your strength-training journey to the next level by finding out what your one-rep max is and using it to get closer to your goals!

How to Find Your One-Rep Max
Photo by Victor Freitas / Unsplash
María Rubio María Rubio
6 min read

If you’re in the fitness world, particularly one that’s focused on strength training, you might hear a lot of different strength-related terms being thrown around, such as sets and reps, progressive overload, and a very common one: one-rep max.

Simply put, your one-rep max is a way of measuring how strong you are, and it varies a lot from person to person. Advanced lifters have a higher one-rep max than beginners because they’ve had the time to properly train and get stronger with time, while beginners are just starting their strength-training journey. This isn’t just a way to brag to fellow gym-goers – it can be an incredibly useful tool during your workouts!

So, if you have serious muscle-building goals and want to maximize your gains and make progress, knowing your one-rep max is a must! We’ll tell you everything you need to know about it, from what it is and why you should know it to how to measure your one-rep max for a better fitness journey. So let’s get started!

What is a one-rep max?

Your one-repetition maximum, one-rep max, or simply 1RM refers to the maximum amount of weight that you’re able to lift in one repetition while exerting maximum effort. In simpler terms, your one-rep max is the absolute heaviest that you can lift at once. You can think of it as your personal lifting record!

So, why should you know your 1RM?

Measuring your one-rep max is a very precise way of testing your overall strength and power, while also giving you a marker to keep track of your improvement and see how much progress you’ve made. At first, your one-rep max will be on the lower side since you’re new with weights and you haven’t built a lot of muscle yet, but this number will increase in time as you keep getting stronger.

Not only that but knowing your one-rep max is also helpful when it comes to following exercise directions and creating or modifying your own fitness routine. For example, you could perform a specific number of reps when bench pressing and add more weight or reps as you make progress, or you could always perform at the same rate according to your current 1RM, such as doing 5 reps at 85-90% of your 1RM. That way, you will naturally follow your gradual improvement while making sure you’re not doing too little or too much.

All in all, measuring your one-rep max is a great way to gradually see your improvement and stay motivated while also having a clearer picture of how your workouts should go. This way, you can plan more effectively for your goals to reach them faster and more safely!

What to know before measuring your one-rep max

There are a few steps in between deciding to calculate your one-rep max (1RM) and actually picking up the weight, so let’s go over the main things to keep in mind when measuring.

First of all, you need to assess your current fitness level. If you’re a beginner or even an intermediate lifter, knowing your one-rep max isn’t absolutely necessary, but it’s good to have a rough idea of what your current limitations are. On the other hand, if you’re an advanced lifter, knowing your one max rep is crucial to keep making progress since you’ve already built a lot of strength and technique, especially if you have weightlifting or powerlifting competitions in mind.

If you’re an absolute beginner though, finding your 1-rep max can wait until you’ve mastered the proper form and technique in the weightlifting exercise that you want to test. This is because exerting maximum effort in a single repetition is very draining and can even be dangerous if performed incorrectly, even more so when you’re not used to testing your strength, so keep this in mind!

There are a few effective exercises that are good for testing, but some of the most popular ones are back squats, deadlifts, and bench presses. These weightlifting exercises are commonly found in most strength training routines because of how effective they are, and they’ve been proven as a valid and reliable way to measure your 1RM.

That said, strength is exercise-specific. While it’s a great indicator of your overall strength, your one-rep max will not be the same in both the bench press and the back squat, because one is upper-body and the other is lower-body. You can test each major part of your body for a more accurate overview (such as the back, legs, and arms/shoulders/chest), or just the one you’re more interested in for your goals!

Here are other key things to keep in mind before measuring your one-rep max:

  • Rest for at least 24 hours before testing your 1RM. You will be exerting maximum effort during your testing, which means that your muscles should be well-rested before trying. This will help you avoid discomfort, injury, or getting an inaccurate result, so no heavy lifting before your test!
  • Always have a spotter with you. When the moment comes, you don’t want to find yourself lifting more than you can handle without anyone to help you lower the weight or get back into the initial position. This is why you always start slow at first, but having someone else looking after you is still crucial.
  • Warm up correctly before testing. As with any regular workout, warming up your muscles and getting them ready for what’s about to come is essential to avoid discomfort or injury during your lifts. And since you’re going to be giving all you’ve got during your testing, you need to make extra sure that your muscles will be able to handle it. Also, remember to cool down after too!

How to test your one-rep max

Now that you know what it is and how to prepare for it, you’re ready to measure your one-rep max. There isn’t a single one-rep max formula or correct way to do this, but this is one of the most approachable methods, especially if it’s your first time testing:

Choose the exercise and warm up accordingly

Before doing anything, you need to pick which exercise you’re going to perform so you can prepare yourself for it while warming up.

Your warm-up should consist mostly of dynamic stretches and movements that mimic the exercise you’ll be using for testing so you can prepare your body for that specific movement, as well as some light cardio to get your heart pumping and your blood flowing. Aim to warm up for at least 15 to 25 minutes.

Perform a few reps of the exercise with half of your expected 1RM

Mentally calculate how much your 1RM will be based on your current fitness level and lifting history, then use 50% (half) of it to perform 6-10 reps.

For example, if you estimate that your one-rep max will be around 200 lb, pick up a weight that’s around 100 lb and use it to perform your first reps. This is so you can break into the exercise using weight to prepare your body for what’s next. After this, rest for at least two minutes before continuing to the next step.

Increase the weight from 50% to 80% of your expected 1RM

Now things are getting serious. Instead of lifting half of what you think your one-rep max will be, lift 80% of that number. So, instead of that initial 100 lb, you’re going to load your bar with 160 lb (80% of 200 lb).

With this weight, only perform 2-3 reps, then rest for at least one minute before continuing to the next step. You’ll start reaching your limit soon, so you need to keep the reps lower to make sure you can finish your testing successfully.

Keep incrementing by 10% after each rep until you reach your limit

The time for the real test has come. Add more weight in 10% increments, performing one single rep, then rest for at least two minutes until you feel like you can’t add more weight.

Following the 200 lb example, your next lift would be 180 lb, rest for 2 minutes, then lift 200 lb, rest for 2 minutes, lift 220 lb, and so on. Remember to keep it at just one rep, and don’t forget about resting between each rep. If you feel like adding 10% is too much but you feel like you can still add more, try adding 5%. Your absolute 1RM will be the last rep that you can successfully lift with proper form and technique.

And that’s it! You’ve measured your one-rep max. This isn’t something that you need to do often, in fact, it’s not recommended to do it more than once or twice a year. It is a very draining process, so maxing out on an exercise shouldn’t be a recurrent thing if you want to keep your muscles healthy!

Take your workouts to the next level by knowing your one-rep max

As we previously said, if you’re a beginner or an intermediate lifter, this isn’t strictly necessary, but knowing your 1RM is a really powerful tool when it comes to creating your workouts and making them work for you! This is particularly important if you have muscle-building goals and eventually want to enter strength training competitions, but it can also be incredibly helpful for casual lifters that enjoy making organic progress.

And if you need some help building strength toward your next 1RM test, check out the Fit With Iulia app! Iulia creates weekly goal-focused workouts with a variety of different exercises so you can achieve your strength-training goals safely. Try your first workout for free by downloading the Fit With Iulia app, choosing a goal, and trying the first workout of any goal – no subscription required!