Mass JYM Study Diet

The nutrition study participants will follow during the Mass JYM Study.

Written By Jim Stoppani, PhD

Updated May 14, 2024

The diet you'll be following is a critical part of the study. It's designed to promote muscle building as well as fat loss, so it's important that you stick to the macronutrient breakdowns as strictly as possible and consume your mass-gaining supplement (shake) as directed.

The first you'll need to do will happen before starting the actual diet: Record everything you eat for 3 days. Use whatever app you like for this; we recommend MyFitnessPal.com, which makes it easy to input all meals, foods, and beverages.

The purpose of the 3-day diet record is to determine your current average calorie consumption; the Mass JYM Study diet will be based off of this. More specifically, on the Mass JYM Study diet, you will be consuming 500 calories more per day than your current average calorie intake.

For example, if your 3-day diet record shows calorie consumptions of 3,457 calories on day 1; 3,287 calories on day 2; and 3,341 calories on day 3, that averages to 3,362 calories.

On the Mass JYM Study diet, your daily calorie consumption will be: 3,362 + 500 = 3,862 calories

Calories are only one part of the equation. Your daily macronutrient breakdown will be based off of your current bodyweight, as followings...

Macronutrient Breakdown:

Protein: 1.5 grams per pound
Fat: 0.5 gram fat per pound
Carbohydrates: remainder of calories (ie, remaining calories divided by four equals grams of carbs per day)

Using the above 3-day diet example, here's how the daily diet would look with a study participant weighing 200 pounds:

3,362 + 500 = 3,862 calories/day

Protein – 1.5g/lb x 200lb = 300 g x 4 cal/g = 1,200 calories

Fat – 0.5g/lb x 200lb = 100 g x 9 cal/g = 900 calories

Carbs – 3,862–1200–900 = 1,762 cals / 4 cal/g = 440 grams

Of the 3,862 daily calories, 1,400 calories come from shakes and 2,462 calories come from food.

Total macros for the day from the entire diet (shakes included) would be:

Protein – 300 g
Fat – 100 g
Carbs – 440 g

Total macros for the day without shakes (from food only) would be:

Protein – 150 g
Fat – 80 g
Carbs – 285 g

Total macros for the day from shakes (5 shakes per day, 280 calories per shake, 1,400 calories total per day from shakes) would be:

Protein – 150 g
Fat – 20 g
Carbs – 155 g