1. What is the One-Rep Max?

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

2. How Does the Calculator Work?

The calculator uses the following formula:

Where:

• \( bench \) — Weight lifted (kg or lbs)
• \( reps \) — Number of repetitions completed

Explanation: This formula estimates your one-rep max based on how many reps you can perform with a submaximal weight.

3. Importance of 1RM Calculation

Details: Knowing your 1RM helps in designing training programs, setting appropriate weights for different rep ranges, and tracking strength progress over time.

4. Using the Calculator

Tips: Enter the maximum weight you can lift for the given number of repetitions. For best results, use a weight you can lift for 2-10 reps. All values must be valid (weight > 0, reps between 1-30).

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this 1RM estimation?
A: This formula provides a good estimate for most people, but actual 1RM may vary based on individual factors like muscle fiber composition and training background.

Q2: Should I actually test my 1RM?
A: Direct 1RM testing can be risky for beginners. This calculator provides a safer alternative, though experienced lifters may benefit from occasional actual 1RM tests.

Q3: Does this work for other exercises?
A: While designed for bench press, it can provide rough estimates for other compound lifts, though accuracy may vary.

Q4: How often should I recalculate my 1RM?
A: Every 4-8 weeks is reasonable, or whenever you can complete more reps with the same weight.

Q5: Why does the formula use 30 in the denominator?
A: The number 30 is an empirically derived constant that provides the best fit for the relationship between submaximal reps and maximal strength.