Comparing one repetition maximum and three repetition maximum between conventional and eccentrically loaded deadlifts

Area of Science:

• Sports Science
• Biomechanics
• Strength and Conditioning

Background:

• The deadlift is a foundational exercise for developing strength and power.
• Understanding the relationship between different deadlift variations and their maximal strength outputs is essential for program design.
• Accurate estimation of one-repetition maximum (1RM) is critical for effective load prescription in training.

Purpose of the Study:

• To compare the 1-repetition maximum (1RM) and 3-repetition maximum (3RM) between conventional and eccentrically loaded deadlifts.
• To determine the accuracy of estimating 1RM deadlift from a 3RM test.
• To assess the interchangeability of deadlift variations in athletic training programs.

Main Methods:

• Fifteen NCAA Division 1 football players participated in the study.
• Maximal strength testing was conducted for both conventional and eccentrically loaded deadlifts, measuring 1RM and 3RM.
• Statistical analyses included dependent t-tests and Pearson correlations to compare strength measures and estimate accuracy.

Main Results:

• No significant difference was found between the 3RM and 1RM for either the conventional or eccentrically loaded deadlift.
• The 1RM conventional deadlift was accurately estimated from the 3RM (r = 0.91), but the estimate was significantly lower than the actual 1RM.
• The 1RM eccentrically loaded deadlift estimation from the 3RM showed a strong correlation (r = 0.84) and was nearly significantly lower than the actual 1RM.

Conclusions:

• Conventional and eccentrically loaded deadlifts may be used interchangeably in training programs.
• Strength coaches should prioritize direct 1RM testing over 3RM estimation for optimizing deadlift training loads.
• Incorporating varied ground-based movements enhances athlete strength and power development.