Optimum Nutrition Serious Mass
ON Serious Mass is the benchmark weight gainer, delivering roughly 50g of protein and over 1200 calories per large serving to support a calorie surplus for those struggling to gain. Servings are big, so many use a half scoop, and the calorie density and reliability are excellent.
Pros
- Very calorie-dense
- Trusted formula
- Good flavours
Cons
- Huge servings
- High in sugars