Altitude and Athletic Performance: Evidence From NCAA Men's Basketball

Does geographic altitude amplify home-court advantage in NCAA men's basketball? Using roughly 195,000 team-game observations from nearly 100,000 games over 2005–2025, I show that programs at 5,000 ft enjoy about 2.0 additional points of home advantage relative to sea-level programs, driven primarily by shooting efficiency. A conceptual framework predicts this pattern: altitude raises the marginal cost of effort for visiting teams relative to adapted home teams. Consistent with a differential-adaptation mechanism, the effect is nonlinear and largest above 3,000 ft, and a neutral-site placebo test finds no effect, though the small neutral-site sample limits its power. The point-margin effect translates into a higher home win probability (roughly 6 percentage points at 5,000 ft) and a net gain of about 0.7 wins per season. These findings have implications for tournament design, betting markets, and competitive balance.