FAST FUEL FOR RUNNERS, HIKERS, BIKERS, & OTHER ENDURANCE ATHLETES: These gel packs are the perfect source of energy to power you through to the finish line. Each flavor offers different levels of caffeine & sodium for energy. PERFORMANCE-ENHANCING CAFFEINE TO AVOID THE BONK: Caffeine is an effective ingredient for energy. 5 flavors contain added caffeine: Chocolate Cherry, Mocha, Double Expresso, Citrus, & Strawberry. CLIF uses green tea extract as the caffeine source. CARBOHYDRATES FOR ON-THE-GO ENERGY: Consuming carbs during activity enhances performance by proving working muscles with a continuous supply of energy. If carbs are consumed during activity, the body can sustain activity for a longer period of time.