What Our Gearhead® Experts Are Saying:"GU Original Gels are my go-to for endurance efforts. They’re compact, easy to take mid-run, and give me a reliable energy boost without any stomach issues. The variety of flavors also keeps things interesting on long days."From start lines to summits, GU Original Energy Gels have fueled endurance athletes for decades—and for good reason. Each packet delivers a precise blend of fast-acting and long-lasting carbohydrates to help sustain energy without the sugar crash. Whether we’re running trails, riding centuries, or grinding out a climb, these compact gels are easy to stash and even easier to digest on the go. Electrolytes help replenish what’s lost in sweat, while branched-chain amino acids protect working muscles and support mental focus through long hours of effort. With a wide range of flavors—including caffeine-free options—there’s a gel to match every taste and training plan.