America's #1 Pre-Workout Brand‡ Explosive Energy & Performance Naturally & Artificially Flavored Dietary Supplement 30 Servings NSF - Certified for Sport CarnoSyn - Carnosine Synthesizer NutraBolt Pre-Workout Energy C4 Sport, taken 30 minutes prior to exercise, provides a boost of energy and focus to maximize your workout. NSF - Certified for Sport The NSF Certified for Sport Program helps athletes, coaches and trainers make more informed decisions when choosing supplements. The program is recognized by the NFL, NFL Players Association, MLB, MLB Players Association, PGA, LPGA, and Canadian Centre for Ethics in Sports. The NSF certification mark on our products helps athletes of all levels buy our supplements with confidence. Certified supplements must meet rigorous standards that include comprehensive lab testing and extensive evaluation of the manufacturing process to ensure contaminated substances or hidden ingredients are not added to a product. ‡ Based on sales of C4 brand products in the U.S.A. from 2014 to present.