NZProtein Mass Gainer's are packed with high calories, perfect for gaining muscle mass. In addition, these extra calories can give you a boost of energy for post-workout recovery. But, we like to spice things up a bit and offer a little cheat-shake indulgence (don't worry, it'll be our little secret). It may be a bit naughty, but it's oh-so-delicious, and that's why we made it this way.