1. What is the 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. It's a standard measurement used to assess strength and to determine appropriate training weights.

2. How Does the Calculator Work?

The calculator uses the Epley formula:

Where:

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

Explanation: The formula estimates your one-rep maximum based on how many reps you can perform with a submaximal weight. The more reps you can do, the further your estimated 1RM will be from the tested weight.

3. Importance of 1RM Calculation

Details: Knowing your 1RM helps in designing strength training programs, tracking progress, and setting appropriate weights for different rep ranges (like 70% of 1RM for hypertrophy training).

4. Using the Calculator

Tips: Enter the maximum weight you can lift for a given number of reps (ideally between 2-10 reps for best accuracy). The calculator works best when you test with weights that allow 2-10 reps before failure.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is the Epley formula?
A: The Epley formula is reasonably accurate for most people in the 1-10 rep range. Accuracy decreases with higher rep counts (>10 reps).

Q2: Should I actually test my 1RM?
A: While estimation is useful, actual 1RM testing (with proper warm-up and safety precautions) is more accurate but carries higher injury risk.

Q3: Does this work for all exercises?
A: It works best for compound lifts like bench press, squat, deadlift. Accuracy may vary for isolation exercises.

Q4: How often should I calculate my 1RM?
A: Every 4-8 weeks is reasonable to track strength progress without excessive testing.

Q5: Are there other 1RM formulas?
A: Yes, other common formulas include Brzycki (1RM = weight / (1.0278 - 0.0278 × reps)) and Lombardi (1RM = weight × reps^0.1).