Bench Press Calculator

Bench press formulas

One repetition maximum for bench press is one of the most commonly determined values in the field of weight training.

1RM is defined as the amount of weight, in either lbs or kg, that a person can lift during a single repetition. This is a measure of the maximum strength of a weightlifter.

The calculator allows the user to input weight in two measurement units, to select a number of repetitions from 1 to 20 and to test any of the 7 formulas, in any combination they wish to use.

The 1RM formulas are:

1. Brzycki:

1RM = W x 36 / ((37 - r))

2. Epley:

1RM = W x (1 + r/30)

3. Lander:

1RM = (100 x W) / (101.3 - 2.67123 x r)

4. Lombardi:

1RM = W x r^0.10

5. Mayhew:

1RM = (100 x W) / (52.2 + (41.9 x e^{(-0.055 x r)}))

6. O'Conner:

1RM = W x [1 + (0.025 x r)]

7. Wathan:

1RM = (100 x W) / (48.8 + (53.8 x e^{(-0.075 x r)}))

Please remember ...

In order to make sure you exercise correctly, there are some things to keep in mind:

■ Maintain a tight grip with the bar and keep your chest in thoracic extension during the exercise;

■ Make sure you keep your elbows at an angle of 45 degrees from your side;

■ Breath while taking the weight;

■ While lifting you need to keep your back, hips and glutes contracted;

■ At the end of the movement, lock out your elbows but continue the thoracic extension.

References

1. Brzycki M. (2012) A Practical Approach To Strength Training. Blue River Press.

2. Lander JE, Bates BT, Sawhill JA, Hamill J. A comparison between free-weight and isokinetic bench pressing. Med Sci Sports Exerc. 1985; 17(3):344-53.

3. Mayhew JL, Johnson BD, Lamonte MJ, Lauber D, Kemmler W. Accuracy of prediction equations for determining one repetition maximum bench press in women before and after resistance training. J Strength Cond Res. 2008; 22(5):1570-7.