1. What is One Rep Max (1RM)?

The one-repetition maximum (1RM) is the maximum amount of weight you can lift for one repetition of a given exercise. It's a standard measure used to assess strength and to determine training loads.

2. How Does the RPE-Adjusted Calculator Work?

The calculator uses a modified Epley formula with RPE adjustment:

Where:

• \( weight \) — Weight lifted in kilograms
• \( reps \) — Number of repetitions performed
• \( RPE\_factor \) — Adjustment based on Rate of Perceived Exertion (1.0 for RPE 10, higher for lower RPE)

Explanation: The standard Epley formula estimates 1RM from submaximal loads, while the RPE adjustment accounts for how hard the set felt.

3. Importance of RPE in Strength Training

Details: Rate of Perceived Exertion (RPE) is a subjective measure of exercise intensity. Incorporating RPE provides more accurate 1RM estimates when not training to true failure.

4. Using the Calculator

Tips: Enter the weight lifted in kg, number of reps performed, and select the RPE of the set. For most accurate results, use data from sets of 1-10 reps at RPE 7-10.

5. Frequently Asked Questions (FAQ)

Q1: Why use RPE-adjusted 1RM instead of standard formulas?
A: RPE adjustment accounts for submaximal efforts, providing more accurate estimates when not training to true failure (RPE 10).

Q2: What's the most accurate way to determine 1RM?
A: Actually performing a 1RM test is most accurate, but this calculator provides a safer alternative for most trainees.

Q3: How often should I test or estimate my 1RM?
A: Every 4-8 weeks for most trainees. Frequent testing can interfere with progress.

Q4: Are there limitations to this calculation?
A: Accuracy decreases with very high reps (>10) or very low RPE (<7). Best for compound lifts like squat, bench, deadlift.

Q5: Should I use this for all exercises?
A: It works best for compound lifts. For isolation exercises or endurance-focused training, other metrics may be more appropriate.