Question 1

What is a one-rep max (1RM)?

Accepted Answer

Your one-rep max is the maximum amount of weight you can lift for a single repetition of an exercise with proper form. It is the gold standard for measuring strength and is used to calculate training percentages for programs like 5/3/1, Starting Strength, and many others.

Question 2

Which 1RM formula is most accurate?

Accepted Answer

All four formulas (Epley, Brzycki, Lander, Lombardi) give similar results within 2-3% of each other for rep ranges of 1-10. The Epley formula is the most widely used. The average of all four is generally a good estimate when you are between formulas.

Question 3

How accurate is a calculated 1RM?

Accepted Answer

Formulas are most accurate in the 1-5 rep range. For 8+ reps the estimate becomes less reliable because endurance and form breakdown play a bigger role. For a true 1RM, you should test it directly with proper warm-up and a spotter.

Question 4

How do I use 1RM to plan my training?

Accepted Answer

Multiply your 1RM by a training percentage: 50-60% for hypertrophy/endurance, 70-80% for strength, 85-95% for power, and 95-100% for max effort singles. Most linear periodization programs work in the 70-85% range for the bulk of training.

📊 Formulas

🎯 Training Zones