The more you eat the more your stomach will expand and the hungrier you will get day by day. Stop eating what you think is healthy and start eating what you think you can get down you need to double your calories.
I think Matt's key to getting in extra calories is to drink them, a lot easier than eating them.
Use a shake that has real food in it, oats, bananas, PB, Whey, milk, eggs etc..
A blender full each AM, put it in the fridge, have a drink w/ each meal throughout the day, etc. His 2 K calories will easily be 4K... (eat 2K, drink 2K).
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Whey protein powder (2 scoops)
Full cream milk or any other milk of your choice (2 cups)
Steel-cut Oats (2 cups)
Bananas (2)
Peanut butter (2 tablespoons)
Honey (1 tablespoon)
Blueberries (1 cup)
Raspberries (1 cup)
Nutritional FactsCalories: 2137Net Carb: 258g
Total Fat: 55g
Protein: 117g