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. For bench press, it's a common measure of upper body strength.

2. How Does the Calculator Work?

The calculator uses the following equation:

Where:

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

Explanation: This formula estimates your 1RM based on how much weight you can lift for multiple repetitions. The more reps you can do with a given weight, the higher your estimated 1RM.

3. Importance of 1RM Calculation

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

4. Using the Calculator

Tips: Enter the weight you lifted (in kg or lbs) and the maximum number of reps you performed with that weight. Use the heaviest weight you can lift with good form for accurate results.

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: What's the best rep range to use for estimation?
A: The formula works best when using results from 2-10 reps. Extremely high rep sets (15+) may not estimate 1RM as accurately.

Q3: Should I actually test my 1RM?
A: While estimation is safer, experienced lifters may benefit from occasional actual 1RM testing with proper warm-up and spotters.

Q4: Does this work for other exercises?
A: This formula works reasonably well for most compound lifts, though some exercises may have slightly different conversion factors.

Q5: How often should I recalculate my 1RM?
A: Every 4-8 weeks is typical, or whenever you significantly increase your training weights.