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1RM Training Guides

Practical guides to strength training, 1RM estimation, and progressive overload.

Your one rep max is the heaviest weight you can lift once with good form, and it is the reference point almost every strength programme is written against. Prescriptions like “3 sets of 5 at 80%” are meaningless without it, which is why estimating it accurately matters more than it first appears.

Testing a true max is slow, taxing and carries real risk, particularly without a spotter. Estimation formulas exist so you can infer the number from a set you have already done. Feed in a weight and the reps you completed, and the equation projects the single you could have managed.

The two formulas in common use, Epley and Brzycki, agree closely in the low rep ranges and diverge as reps climb. Neither is universally more accurate. Both become progressively less reliable above about ten reps, because at that point you are measuring muscular endurance as much as maximal strength, and the relationship between the two varies a lot from lifter to lifter.

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Getting a usable number

For the most reliable estimate, use a set taken close to failure in the three to six rep range, with the same technique and equipment you would use for a true max. A set of twelve taken well short of failure will produce a flattering number that falls apart the moment you load the bar.

Treat the result as a working figure to programme from rather than a personal best to claim, and recalculate it every few weeks as your training progresses. Estimates also drift between lifts: the formulas tend to fit the squat and deadlift better than they fit the bench press or overhead press, where smaller muscle groups fatigue faster.

Jump straight to a tool: 1RM calculator, bench press, squat, deadlift, overhead press.