More about Max Weight and One Rep Max

You’ve probably heard it a million times. High weight, low rep to build muscle; low weight high rep to tone muscle. But, how high is high enough? The answer to that has to do with a number called “max weight” or “one rep max.”

You can follow your feelings and lift what you feel is right as many times as it feels right. And that’s fine. Everyone starts out this way and some people never really refine their approach beyond this. But, if you’re a little more analytical, you might like to be able to mathematically define “high weight.” You do that by taking percentages off of your max weight.

What Is One Rep Max?

Discovering your max weight is simple – but it isn’t easy. It starts with how you think about a lift. Instead of thinking about how many you should do, think about doing just one. If you were going to do a lift just one time, how much could you lift while maintaining proper form? This is your max weight, also called your “one rep max” (Schuler & Cosgrove, 14).

That does mean that every lift that you know has its own max weight. You determine your max weight through experimentation – by finding out exactly how much you can move in exactly one perfectly executed lift.

One quick side-note before we move on: we say “weight” and “lift” throughout this article, but that’s essentially just a linguistic carry over from the all-free-weights-all-the-time days. If you use cable machines, you might not “lift” anything and your workout might not be measured in “weights” – and that’s fine. You can still determine and use your one rep max in the same ways.

How to Determine Your One Rep Max

Form is very important. Not just for optimizing the effectiveness of your workout, but for minimizing injury. Don’t go compromising form to struggle through a lift with an insanely high weight. You’ll be putting yourself in danger and cheating your workout.

That said, if you think that honestly determining your one rep max for an exercise still sounds dangerous, it can be. Even when trying to lift as much as you can, don’t push yourself to lift more than you can. 

Even if you don’t usually workout with a partner, please do get a spotter if you’re working with free weights. That goes double for exercises that have you lifting weights over yourself, like bench presses.

Keep in mind too, that your max weight is meant to change as you get stronger. It’s better to be cautious and define your max weight lower than it actually is and bump it up as you progress through your weight lifting journey. The alternative could be defining your max weight as higher than it actually is and ending your weight lifting journey prematurely.

Determining your max weight for a bunch of exercises can be tiring. You might want to set aside a day just for defining max weights. Or, maybe you want to figure out a few max weights for varying exercises each day and spread it out. It all depends on how many exercises you want to define a max weight for and what areas of your body they target.

If you like to incorporate lifts for every major muscle group into every workout, you might be able to determine your one rep max for a couple of workouts each day. If you dedicate each day to targeting a specific area you might want to spread these experiments out a bit more.

Incorporating Your Max Weight into Your Lifting Regimen

You’re not setting out to determine your one rep max  for an exercise so that you can lift that amount one time every day. You’re determining your max weight so that you can build it into your weight lifting regimen.

Building With a High Percentage of Your Max Weight

This brings us back to the high weight, low rep mantra for building. We introduced this idea in our article on building and toning, where we also gave a quick top-down intro to one rep max.

When we say “high weight” we mean up to eighty percent of your defined one rep max for that exercise. When we say “low rep” we mean about ten. If this is all a bit much for you, our article on determining the “right amount of weights” says that the right amount of weights is however much you can lift with good form about eight to twelve times.

You can also calibrate these things with sets up reps. Go for fewer than ten reps at eighty percent of your max weight if you plan on doing multiple sets. If you only plan on doing one set, go for the full ten at eighty.

Toning With Low Percentage of Max Weight

But, what about low weight, high rep for toning?

When we say “low” what we really mean is “low compared to high,” not “low compared to max weight.” Even in your toning, you should be above fifty percent of your one rep max. You might aim for as high as seventy percent, but aim for fifteen, or twenty reps. 

Again, these are guidelines, so increase or decrease weight, increase reps, and manage your rep count by dividing your total number of reps into smaller sets with breaks in between to rest, catch your breath, and stay hydrated.

Hybrid Models for Gradual Building, Warm-Ups, and Cool-Downs

There are two hybrid models that combine low and high reps with low and high weights that you also might want to consider. Some help you cool down or warm up, some help you get a balance of building and toning.

Either way, changing up your weights help to develop your muscles in different ways, develop different fibers within your muscles, and keep your muscles from getting too used to your workout – that can cause plateaus in your gains.

Lots of Super Low Weight

The first does involve super low weights. We’re talking twenty or thirty percent of your one rep max for the workout. Rapid fire a single set of five or ten reps, and then jump up to your normal weight and rep count for that workout. 

The idea is to warm up the muscles that you’re about to use and get the blood pumping before you settle into the real workout. You can also incorporate this after your regular set, again with the intention of really moving the muscles and getting the blood flowing. That blood carries away cellular debris and might reduce your natural post-workout muscle soreness.

A Little More of the Heavy Stuff

The next hybrid approach takes things the other way around. 

If you’re more about toning, do your normal toning rep count with your normal toning weight, but skip the last set. Then, increase your weight to eighty percent or more of your defined one rep max for that exercise and throw in a mini-set of five reps or even fewer with the intention of focusing on toning without avoiding gradual building.

A Creative Way to Think About Sets

If you’re really into sets, or if this set-heavy article has you thinking about them more than you used to, consider incorporating a number of sets of varying difficulty.

Go for the low-to-high model: one set well below your max weight to get the juices flowing, one toning set, one building set. Or, the bell-curve model: One quick set well below your one rep max on either end of your workout to ease yourself in and out with toning and/or building sets in-between.

Use your imagination. Go crazy. Then, leave a reply to this article sharing your favorite combo and why it works for you.

How Often Should You Recalculate Your One Rep Max?

We’ve mentioned a couple of times that your max weight will change as your muscles grow through your workout. We’ve also mentioned that how you define your one rep max should change too so that you can keep advancing your goals forward. So, how often should you update your max weight?

That depends on what purpose your workout serves for you and how ambitious you are to level it up. If you lift competitively, you’re probably constantly pushing the boundaries of your ability – and updating your max weight definition along the way. However, this isn’t for everybody.

If you’re not a competitive lifter but you still actively want to bulk muscle, check back in with the max weight for a workout whenever it starts to feel too easy. If you think that you might be able to up your weights on a workout, try the next incremental weight up from your old one rep max. How fast this changes depends on your body and the frequency and variety of your sessions.

If you’re more interested in toning, bless you for reading this far into the article, but your one-rep max is probably more valuable as a conversation piece than anything else. As long as you feel like your workout is challenging and you increase weight and rep to keep it that way, you’re probably exactly where you need to be.

What Can You Bench? How Many Times?

Most people are familiar with max weight if they brag about how much they can bench. But, if you’re serious about your weight lifting journey, your one rep max should be a cornerstone of your lifting regimen. 

Further Reading

Schuler, Lou & Cosgrove, Alwyn. “The New Rules of Lifting for Life.” Avery. New York, NY, USA. 2012.