How to Estimate Your One-Rep Max Without Testing It

Earlier this year I wrote a tip about how ​“healthy” behaviors—and their results—follow a bell curve​. And I gave an example of how I set a personal record (PR) in the deadlift about a decade ago by following two challenging programs back to back—but how pushing too hard messed me up for a while.

I also said that I had been considering running through the second program again—while applying the lessons I had learned the first time around and accounting for my current age and training status. That opportunity is here.

The semi-annual ​Tactical Strength Challenge​^†—a one-rep max (1RM) deadlift, strict pull-ups for reps (or flexed-arm hang for time), and a 5-minute kettlebell snatch test—is taking place the last Saturday of October. A number of TNT members usually participate, so the group training program design for the three months leading up to the event is always geared toward improving the tested lifts.

This time around, I decided to add that second deadlift program into the mix. Of course, I don’t want anyone to feel the way I felt after my first time following it, so I slightly decreased some of the percentages that they’ll be using throughout the program. And I decided this would be the perfect opportunity to do the program again myself.

In order to do this (or any) strength program effectively, knowing or estimating your 1RM is vital. That’s because most progress is made when you regularly lift moderately heavy weights (70-90%) relative to your current capacity (1RM). Which means that not knowing your current capacity is like shooting in the dark—maybe you’ll get lucky and hit your target, but probability says you’ll miss.

Since I hadn’t deadlifted anything heavy in quite a while—it’s probably been since before COVID—I needed a safe way to find that number. Here’s how I went about doing that, and a few subtleties to consider when you do it for your own training.

Estimating 1RM from lighter sets

It’s probably obvious that as a weight increases closer to your maximum capacity you’ll be able to lift it fewer times in any given set. By definition, you can lift your 1RM once. Something significantly less you might be able to lift for 10 reps; something in between perhaps for 5.

What you might not realize is that we have a reasonably accurate idea of how many reps the average individual can perform at specific percentages of his/her max. This means calculating/estimating a 1RM is a basic arithmetic problem if you know how many reps you can perform with a submaximal weight.

I’ve previously shared ​a table containing such estimates​ (see the footnote in that post). The percentages do vary slightly from person to person and from lift to lift. Still, it’s useful information to have at your fingertips at times when testing your actual 1RM is either infeasible or unsafe—such as when minimal equipment is available, you’re an inexperienced lifter who hasn’t yet learned how to control a very heavy weight, or you’re returning after an injury or long time off (from training or a specific lift).

Although I’ve lifted regularly for the past 30+ years, I currently fall into the latter category when it comes to deadlifting. Which is why I didn’t test my 1RM outright and instead used this estimation method—with a slight caveat.

To some extent, different limits are equally hard on the body. Meaning: A one-rep max is your limit for a single rep. Although your three-rep or five-rep maxes are lighter weights, they’re still your limits for three or five reps. And that’s still exhausting.

Rep max/percentage tables assume that you’ve done as many reps as you possibly can with a submaximal weight. But I left a couple reps in the tank on each of my work sets because my “testing” (which I’ll explain shortly) was on a normal training day, I hadn’t deadlifted heavy in a while, and I didn’t want to be sore as Hell for three days afterward. All of which meant that I simply needed to add those reps back into the equation before completing the calculation.

(If you’ve been following my advice about ​stopping your sets with reps in the tank or before rep velocity slows down​, remember to add them back before calculating.)

Methodology & calculations

It should hopefully go without saying, but I’ll do so anyway: warm up before doing any sort of testing.

My typical recommendation is to do 3, 2, and 1 rep, each at an increasingly heavier weight less than your intended “working” or “test” weight. In my case, that was 3 @ 225, 2 @ 275, and 1 @ 315.

I had planned to do 5, 3, and 2 reps for my training/testing that day—but doing a single set is also totally fine if you’re purely testing instead of training. I started at 365 (for 5), and then bumped up to 385 (3) and 405 (2).

Based on experience, I felt like I left 2-3 reps in the tank on the first two sets and 2 reps in the tank on the final set.

Plug those numbers into the percentages from our table, and we get:

Obviously, the final numbers vary slightly—an estimate is still an estimate, of course. But they’re all in the ballpark of one another. And even specifically testing your 1RM is at least a little art. (Could I have done 5 more pounds? Ten? I don’t know because now I’m tired and won’t try it again today…)

That said, numbers calculated from lower repetitions (usually 2-6)—that is, weights closer to whatever your 1RM actually is—tend to be more accurate. So 450—which falls between both 440-455 (the 365-lb calculations) and 445-455 (the 385-lb calculations)—is probably about right.

Putting it into practice

As far as general activity is concerned, there’s certainly nothing wrong with simply grabbing just about any weight and lifting it. But if you want the best results from your training time, then choosing weights more precisely is a better option.

So if your current training plan is based on a tested or estimated value, keep doing what you’re doing. And make sure to re-test occasionally, and adjust your programs accordingly! (I recommend quarterly for the lifts you really care about.)

And if your current training plan isn’t based on a tested or estimated value?

First, give yourself a pat on the back for having been lifting in the first place. That’s still a fantastic thing!

But then also consider doing a couple tests to see how close you are to the weights that will most likely provide the best results—and make adjustments where appropriate. During your tests, aim to stay in the low-rep range. And optimally, leave one rep in the tank—it’ll keep things a little more accurate while also keeping you from feeling too smoked afterward.