Your one-rep max (1RM) is the maximum weight you can lift for a single repetition with full effort. Testing 1RM directly carries injury risk; instead, coaches use sub-maximal formulas. The Epley formula: 1RM = weight × (1 + reps/30). The Brzycki formula: 1RM = weight × (36 / (37 − reps)). Both are accurate to within 5-10% for sets of 1-10 reps. Sets of more than 10 reps produce less reliable estimates. 1RM is used to set training percentages across strength programmes.
Key points
- Epley: weight × (1 + reps/30)
- Brzycki: weight × 36/(37-reps)
- Accurate to ~5-10% within 1-10 rep range
- Used to calculate training percentages