Lombardi adjusted Brzycki's formula using data from athletes in different sports, not just powerlifters.
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The Lombardi 1RM formula is another variation on the Brzycki-style equations. It was developed by Vince Lombardi Jr., the son of the famous football coach.
The Lombardi formula is:
1RM = Weight / (1.038 - (0.0297 x Reps))
Where: Weight = Load lifted (lbs or kg) Reps = Number of reps completed
Compared to Brzycki's original 1.0278 - (0.0278 x Reps), you'll notice Lombardi uses slightly different coefficients of 1.038 and 0.0297.
Lombardi derived these coefficient values by analyzing strength training data from athletes across multiple sports, not just powerlifters. His dataset included athletes from football, baseball, basketball, hockey and others.
Through regression analysis on this multi-sport athlete data, Lombardi found that the 1.038 and 0.0297 coefficients provided the best fit and minimized errors when predicting the athletes' actual measured 1RMs.
The rationale was that by including a wider range of athletes, not just powerlifters, the formula could better generalize across different types of training and body types.
While a small adjustment from Brzycki's original coefficients, Lombardi claimed his formula was more accurate for team sport athletes compared to just using powerlifting-derived prediction models.
The Lombardi formula highlights another example of researchers aiming to fine-tune and validate 1RM prediction equations on specific populations through statistical analysis of representative data.