You should choose a muscle gain setting if you want to build muscle and add weight to your frame. To do this optimally you’ll need to be in a calorie surplus, which means you’ll be eating more calories than your body burns each day.
Put simply, when you’re on a muscle gain setting, you should be prepared to eat a lot of food!
The amount of food that is prescribed will depend on the exact muscle gain setting you choose. The more aggressive the setting, the higher your macro targets and the greater your weekly rate of weight gain will be.
Not sure if the muscle gain goal is for you? Find out by asking yourself these questions:
Do I want to gain weight?
Do I want to maximize my ability to build muscle and get stronger?
Am I prepared to eat a lot of food and follow a weight training program?
If the answer to all of these questions is "yes," then muscle gain is the right goal for you.