Someone say protein
 

PROTEIN

Amino acids*are the building blocks of protein and there are 20 of them. For you to gain and maintain strength and size, protein in the most important macronutrient. To make sure you’re getting enough, don’t rely on your protein powder alone. Be sure to incorporate*good sources of protein, beef, chicken, fish, eggs and dairy.

>> Try to consume at least 1 gram of protein per pound of bodyweight per day.