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Validation of the NFL-225 test for predicting 1-RM bench press performance in college football players
J L Mayhew1, J S Ware, K Cannon
1Human Performance Laboratory, Truman State University, Kirksville, Missouri 63501, USA. jmayhew@truman.edu
Background:
The purpose of this study was to evaluate the accuracy of repetitions-to-fatigue (RTF) using an absolute load of 102.3 kg (225 lbs) to estimate one-repetition maximum (1-RM) bench press performance in college football players using various prediction equations.
Experimental Design:
a prospective study on the association between muscular endurance and muscular strength.
Participants:
260 players from NCAA Division IA (n=43), IAA (n=63), II (n=129), and red-shirts (n=25) were evaluated at the conclusion of a minimum of eight weeks of heavy-resistance training during the off-season.
Measures:
all subjects performed a 1-RM bench press and RTF using an absolute load of 102.3 kg.
Results:
The Mayhew et al. NFL-225 equation nonsignificantly overestimated 1-RM from RTF by 0.5 kg, while the Chapman et al. NFL-225 equation significantly underpredicted by 3.2 kg, although both equations were comparable in the number of players predicted within +/-4.5 kg of actual 1-RM (52% vs 51%, respectively). Only two of nine RTF equations currently in use produced predicted 1-RM values that were not significantly different from actual 1-RM performance.
Conclusions:
Specific NFL-225 equations are more accurate in estimating 1-RM bench press from absolute muscle endurance in college football players than previous published RTF equations. The accuracy of prediction decreases at higher repetitions.
