* ... powerful pumps, muscular endurance, extreme focus, and peak performance. Americas #1 Selling Pre-Workout - Every scoop of C4 Extreme Energy delivers a Next-Level experience with a potent dose of energy, pumps, endurance, performance, and focus, including 3.2g CarnoSyn Beta Alanine, 1g Creatine Nitrate, 1g Arginine AKG, 1g Citrulline Malate, and 300mg caffeine, with zero Sugar, carbs, or calories. Consider C4 Ultimate a masterpiece from pre-workout craftsmen. Caffeine (300mg) Caffeine is a well-studied stimulant that has numerous energy, performance, and even fat-loss benefits. C4 Smart Energy sharpens your attention, boosting memory and performance. Commonly found in bodybuilding supplements, Beta Alanine increases the level of Carnosine in muscle and other tissue. As long as you don’t mind being dosed with 300 mg of caffeine, it’s a good choice for enthusiasts and beginners who want to transition from casual exercise to a more regular routine. Beta Alanine 1500mg. Brain Fuel : C4 Smart Energy. As mentioned above, the dosage of caffeine has been increased in C4 Extreme. This allows you to increase your mental alertness and ability to focus on your form for each of your exercises. C4 Smart Energy features patented, clinically studied Cognizin® and naturally-derived caffeine from green tea to deliver the mental focus you crave. C4 Extreme Energy is a step-up from Original, containing higher doses of its key ingredients. Caffeine, a popular ingredient in products like Cellucor C4, comes with the risk of side effects like increased heart rate, elevated blood pressure, jitters, and sleeplessness. Apart from that, it is essential to remember that GNC Cellucor C4 is a product … Caffeine 135mg.