The Deceleration Paradox: The Faster You Run the Slower You Stop.

Lin, J, Dos'Santos, T, Xu, X, Li, W, and Turner, A. The deceleration paradox: The faster you run the slower you stop. J Strength Cond Res 40(5): 560-565, 2026-This study examined the effect of approach momentum on horizontal deceleration (DEC) performance. Eighty team sports athletes performed 3 maximal horizontal DEC trials from a 15-m approach. Sprint performance was recorded using timing gates, and instantaneous velocity was collected using a radar device. Correlation and multiple regression analysis were conducted to analyze the relationships between DEC-related variables. Between-subject (top 50% vs. bottom 50%) differences in DEC-related variables were also determined. Greater mean DEC was significantly correlated with lower approach momentum (r = -0.354, p = 0.001). Compared with lower DEC performers (in terms of mean and peak values), greater performers showed statistically significantly lower peak approach velocity (ES = 0.41-0.66, p < 0.05) and lower peak approach momentum (ES = 0.48-0.60, p < 0.05). Furthermore, the standardized beta values of the multiple regression analysis demonstrated that body mass is a greater determinant of DEC performance compared with approach velocity. In conclusion, practitioners should be aware that approach momentum (body mass and approach velocity) is a factor influencing DEC performance, and an inverse relationship exists. Thus, to evaluate maximal DEC ability, approach velocity and body mass must be considered.