Creatine
 

This is one of the most studied bodybuilding supplements for the last 20 years or so. It’s a supplement that works without a doubt. It gives you more strength and energy during intense exercise and increases muscle mass. You consume creatine when you eat red meat, but that’s in very low doses – around 3-5 grams per 2 lbs of red meat. There are a few types of creatine on the market, but nothing beats the good old creatine monohydrate. When taking creatine you would want to start with 5-10 grams a day (depending on your weight), divided into two doses.

Partial to Onnit brand creatine monohydrate. Good quality and unflavored. Just toss it in my pre-workout. Only supps I take, aside from protein.