Maxifuel's Viper Boost puts a varied mix of sucrose, rice flour, ground almonds, starches, fructose and glucose syrups under a relatively thick (14 percent) dark chocolate skin.
A relatively low sugar percentage with a high protein and fat content makes it a steady energy delivery bar. Its infamous reputation comes from the caffeine and guarana buzz ingredients for kick-starting workouts or restoring flagging focus in the last gasp of a race.
Like most stimulant-enriched products, tolerance before queasiness kicks in varies between athletes. Add a crash as noticeable as the boost and you need to check how these bars work for you before racing with them. Very pricey, too.