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The NFL Scouting Combine Explains Within-Position Physical Performance Variance But Is a Poor Predictor of Draft
Benjamin P Doyle1, Sean T Stanelle, Steven E Riechman
1Performance and Fatigue Laboratory, Department of Kinesiology and Sport Management, Texas A&M University, College Station, Texas.
Abstract:
Doyle, BP, Stanelle, ST, Riechman, SE, and Mann, JB. The NFL scouting combine explains within-position physical performance variance but is a poor predictor of draft outcomes. J Strength Cond Res XX(X): 000-000, 2026-This study evaluates the National Football League (NFL) Combine's physical performance tests ability to (a) explain performance variance between players of similar positions and (b) predict draft status. Players who completed all combine assessments (n = 3,681) were grouped by position group as quarterbacks, skill (SK), linemen (BIG), and mid-size. Variables included the 6 NFL Combine tests, height, body mass, maximal anaerobic power, and momentum for speed and change-of-direction (COD) tests. Principal component analysis with promax rotation and parallel analysis reduced data dimensionality for each position group. Binary logistic regression with Monte Carlo simulated cross-validation (n = 1,000) examined the impact of identified physical performance components on draft likelihood for each position group. Multivariate analysis of variance with post-hoc testing compared drafted vs. undrafted players' component scores. Four physical performance components explaining meaningful variance were identified: momentum (26.5-36.1% explained), power (22.1-29.5% explained), COD (15.5-19.7% explained), and strength (10.0-11.5% explained; BIG and SK only). Logistic regression indicated that few components significantly influenced draft probability (p < 0.05; SK only). Overall model predictive performance was poor (receiver operator characteristic area under the curve < 0.75). Differences between drafted and undrafted players were found in wide receivers (WR) (power, COD, strength), defensive backs (momentum, strength), and running backs (strength), with undrafted players having unexpectedly superior performance component scores than drafted players across several performance qualities (small-to-moderate effect, p < 0.05). These results suggest that physical performance alone does not account for most variance in draft status once underlying performance thresholds are met. National Football League Combine tests inconsistently predicted draft outcomes but may still guide roster decisions when contextualized as underlying physical performance attributes to highlight individual deficits to evaluate an athlete's fit for team-specific demands.
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