Enter the weight you lifted and the number of repetitions to estimate your one-rep max:
The One-Rep Max (1RM) is the maximum weight that can be lifted for a single repetition for a given exercise. It's a crucial metric in strength training and weightlifting, used to measure progress and determine training loads. While the most accurate way to determine your 1RM is through actual testing, it can be estimated using various formulas based on the weight lifted and the number of repetitions performed.
This calculator uses three common formulas to estimate 1RM:
$$1RM = \frac{Weight}{1.0278 - 0.0278 \times Reps}$$
$$1RM = Weight \times (1 + 0.0333 \times Reps)$$
$$1RM = \frac{100 \times Weight}{101.3 - 2.67123 \times Reps}$$
Where:
Let's calculate the 1RM using the Brzycki formula for someone who lifted 200 lbs for 8 repetitions:
Step 1: Identify the values
Step 2: Apply the Brzycki formula
$$1RM = \frac{200}{1.0278 - 0.0278 \times 8}$$
Step 3: Calculate
$$1RM = \frac{200}{1.0278 - 0.2224} = \frac{200}{0.8054} = 248.32$$
Step 4: Round the result
1RM ≈ 248.32 lbs
Therefore, based on lifting 200 lbs for 8 repetitions, the estimated one-rep max is approximately 248.32 lbs.
This bar chart illustrates the difference between the weight lifted for multiple repetitions (200 lbs) and the estimated one-rep max (248.32 lbs) based on the Brzycki formula. It provides a visual representation of how the 1RM estimation predicts a higher maximum weight for a single repetition compared to the weight used for multiple repetitions.