Clif Shot Blocks are the latest nutrition option for endurance athletes. Shot Blocks come in chewable, 33 calorie cubes, making it easy to customize and track caloric and electrolyte intake during long outings and races. 33 Calories per piece Simple to handle Easy to chew Who needs Clif Shot Blocks? Clif Shot Blocks are primarily used by performance athletes cyclists, runners, mountain bikers, triathletes, adventure racers, etc. However, any performance-oriented athlete needing a quick burst of energy can benefit from Clif Shot Blocks. Caffeinated flavors are not recommended for pregnant women, children, or people sensitive to caffeine. They contain at least 70 mg of sodium and 20mg of potassium per serving (3 pieces). These electrolytes allow electrical impulses to travel properly throughout your body, enabling proper muscle function. When you sweat you start to deplete yourself of these electrolytes. Similar to dehydration, loss of electrolytes first leads to declined performance and can potentially.