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

The 1 Rep Max (1RM) is the maximum amount of weight you can lift for a single repetition of a given exercise. For leg press, it represents your maximum strength capability for one repetition.

2. How Does the Calculator Work?

The calculator uses the Epley formula:

Where:

• \( weight \) — The weight you lifted (kg)
• \( reps \) — The number of repetitions you performed

Explanation: This formula estimates your 1RM based on submaximal loads and repetitions. It assumes a linear relationship between repetitions and percentage of 1RM.

3. Importance of 1RM Calculation

Details: Knowing your 1RM helps in designing training programs, tracking strength progress, and determining appropriate training loads for different rep ranges.

4. Using the Calculator

Tips: Enter the weight you used for your set (in kg) and the number of clean repetitions you performed. The calculator works best for rep ranges between 2-10.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this 1RM estimation?
A: The Epley formula provides a good estimate for most people, but actual 1RM may vary by ±5-10% depending on individual factors.

Q2: Can I use this for other exercises?
A: While designed for leg press, this formula can provide rough estimates for other compound exercises, though accuracy may vary.

Q3: Should I actually test my 1RM?
A: For safety, it's often better to estimate 1RM rather than actually attempting maximal weights, especially for beginners.

Q4: Why does the formula use 30 in the denominator?
A: The number 30 is an empirically derived constant that represents the approximate relationship between repetitions and percentage of 1RM.

Q5: How often should I recalculate my 1RM?
A: Recalculate every 4-6 weeks as your strength changes, or whenever you can complete more reps with the same weight.