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How to Calculate Predicted 1 Rep Max

How to calculate predicted 1 rep. max

It's one thing to train for general health but it's another thing to train for performance and achieve advance features like some of our favorite anime heroes. If you're currently training to improve your one repetition max (1RM) in a specific lift, it's imperative to have a goal. If you're unsure about that goal, below are the steps to teach you how to calculate your predicted one repetition max which can be used as one of your baseline goals.

Step 1: Determine what exercise you want to calculate for predicted one rep. max

Determine which exercise you want to calculate for your predicted 1RM. Will it be for the squat or bench press?

Step 2: Achieve failure up to 10 reps. (cannot be more than 10 reps.)

Test and determine the specified weight that pushes the chosen exercise to failure up to 10 repetitions. For example, I will hit failure at the 10th repetition when squatting 135lbs. (61kg)

Step 3: 2.5 x Rep. Failure Multiply the number of repetitions you can perform on an exercise to failure by 2.5.

(For example, 10 repetitions x 2.5)

Step 4: Determine percentage of 1RM

Subtract that number from 100 to determine the percentage of your 1RM.

Step 5: Retrieve decimal value

Divide the above number by 100 to get a decimal value.

Step 6: Retrieve estimated 1RM

Divide the weight you lifted by the decimal value to get your estimated 1RM


Example 1: Hitting failure at 10th repetition when squatting 61kg (135lbs.)

If you can squat 61kg for 10 reps.

10 reps x 2.5 = 25

100 - 25 = 75

75/100 = .75

Estimated 1 RM = 61kg/0.75 = 81kg

Example 2: Hitting failure at the 5th repetition when squatting 61kg (135lbs.)

5 reps x 2.5 = 12.5

100 - 12.5 = 87.5

87.5/100 = .875

Estimated 1 RM = 61kg/.875 = 70kg

Example 3: Hitting failure at the 8th repetition when squatting 80kg (176lbs.)

8 reps x 2.5 = 20

100 - 20 = 80

80/100 = .80

Estimated 1 RM = 80kg/0.80 = 100kg

Disclaimer: All information presented and written within this article are intended for informational purposes only. You should not rely on this information as a substitute for, nor does it replace, professional medical advice, diagnosis, or treatment. If you should choose to follow or participate in any workout, program or practice, you do so voluntarily and do not hold Initial Mile and it's founder responsible for any cause of injury or death. If you have any concerns or questions about your health, you should always consult with a physician or other health-care professional.


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