1. What Is the 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 common measure of strength in weight training and is particularly important for bench press performance assessment.

2. How Does the Calculator Work?

The calculator uses the Epley formula:

Where:

• \( Weight \) — The amount of weight lifted (kg or lbs)
• \( Reps \) — The number of repetitions performed

Explanation: This formula estimates your maximum strength based on how much weight you can lift for multiple repetitions. The equation accounts for the relationship between submaximal weights and true maximum capacity.

3. Importance of 1RM Calculation

Details: Knowing your 1RM helps in designing training programs, tracking strength progress, and determining appropriate training loads for different goals (strength, hypertrophy, endurance).

4. Using the Calculator

Tips: Enter the weight you lifted (in either kg or lbs) and the number of repetitions you performed with that weight. The calculator works best for rep ranges between 2-10.

5. Frequently Asked Questions (FAQ)

Q1: Why estimate 1RM instead of testing it directly?
A: Direct 1RM testing can be risky, especially for beginners. Estimation formulas provide a safer alternative while still being reasonably accurate.

Q2: How accurate is the Epley formula?
A: The Epley formula is generally accurate within ±5% for most people, though individual variations exist. It tends to be most accurate for 2-10 rep ranges.

Q3: Should I use kg or lbs?
A: The calculator works with either unit - just be consistent in what you use for tracking progress over time.

Q4: How often should I calculate my 1RM?
A: Every 4-8 weeks is reasonable for tracking progress. More frequent calculations may not show meaningful changes.

Q5: Are there other 1RM formulas?
A: Yes, other common formulas include Brzycki, Lombardi, and O'Conner. Epley is one of the most widely used for bench press.