The Brzycki 1RM Formula

The Brzycki formula, introduced by Matt Brzycki in 1993, estimates your one-rep max (1RM) using submaximal lifts, offering a safe alternative to max testing. This guide covers its history, development, and role in strength training.

Matt Brzycki: A Strength Training Expert

Matt Brzycki at Princeton
Matt Brzycki

Matt Brzycki, born in 1957, is a respected strength coach with over 40 years of experience. His career began in the U.S. Marine Corps (1975-1979), where he earned the Leatherneck Award for rifle marksmanship and a meritorious promotion to sergeant. He later served as a strength coach at Princeton University (1983-1984, 1990-present) and Rutgers University (1984-1990), training hundreds of athletes. His book, A Practical Approach to Strength Training, first published in 1989, has sold nearly 35,000 copies across multiple editions and remains a fitness industry staple. In 1999, Brzycki received a Certificate of Recognition from the International Association of Resistance Trainers for his contributions to exercise science.

The Brzycki Formula

The Brzycki formula estimates your 1RM with the equation:

1RM = w / (1.0278 - 0.0278 × r)

The equation can also be written as:

1RM = w × (36 / (37 - r))

Where:

  • w is the weight lifted
  • r is the number of repetitions performed

For example, bench pressing 100 kg for 5 reps yields:

1RM = 100 / (1.0278 - 0.0278 × 5) = 100 / (1.0278 - 0.139) ≈ 112.5 kg

It’s reliable for 2-10 reps, especially for compound lifts like squats, deadlifts, and bench presses, reflecting Brzycki’s focus on high-intensity, submaximal training.

How Brzycki Developed the Formula

In the early 1990s, Matt Brzycki faced a challenge at Princeton and Rutgers: assessing athletes’ strength without the risks of max lifts. Strength training was gaining traction, but direct 1RM testing posed injury risks, especially for collegiate athletes. Brzycki analyzed submaximal lifts (2-10 reps) performed to fatigue, correlating them to maximum potential. He refined the coefficients 1.0278 and 0.0278 based on these observations. Introduced in a 1993 paper and his book A Practical Approach to Strength Training, the formula spread through his coaching clinics, becoming a staple in strength training.

Validation and Accuracy

Research suggests the Brzycki formula is very accurate for bench press 1RM estimates in the 7-10 rep range, as shown in this 2007 study. It may slightly underestimate for very low reps (1-3) due to its mathematical model but it is widely used, cited in over 1,075 studies.

Brzycki’s Significance

Matt Brzycki’s formula reflects his practical approach to strength training. His work at Princeton, Rutgers, and through his influential book has professionalized strength coaching. The Brzycki formula remains a key tool for safe strength assessment, shaping modern training programs.