This study examined lower extremity power performance, using the Margaria-Kalamen Power Test, after a dynamic warm-up with (resisted) and without (nonresisted) a weighted vest. Sixteen (n = 16) high school male football players, ages 14-18 years, participated in 2 randomly ordered testing sessions. One session involved performing the team's standard dynamic warm-up while wearing a vest weighted at 5% of the individual athlete's body weight before performing 3 trials of the Margaria-Kalamen Power Test. The second session involved performing the same dynamic warm-up without wearing a weighted vest before performing 3 trials of the Margaria-Kalamen Power Test. The warm-up performed by the athletes consisted of various lower extremity dynamic movements over a 5-minute period. No significant difference was found in power performance between the resisted and nonresisted dynamic warm-up protocols (p > 0.05). The use of a dynamic warm-up with a vest weighted at 5% of the athlete's body weight was not advantageous for increasing lower extremity power output in this study. The results of this study suggest that resisted dynamic warm-up protocols may not augment the production of power performance in high school football players.