A “gruel diet” sounds pretty painful (or maybe just hard to swallow) for most. During Medieval times, peasants ate this mixture of rice, oats, barley or corn in a watery fashion mixed with cheaper high starch vegetables like potatoes, corn and onions. It was filling and it supplied them with the nourishment needed for survival. Now, a 15-time Australian strongman champion is challenging you to ditch your protein shakes in favor of gruel for one week after reporting a 300g increase in muscle mass. 

Whie he acknowledges that the challenge should not extend past the one week mark for practical health reasons, how was he successful with such a basic, incomplete diet? Was it really that incomplete? Lets break it down. 

How it Works

Gruel covers the basics: vitamins, minerals, carbohydrates and some protein. Glucose is the most readily converted energy source for our bodies, and gruel provides plenty of these simple sugars. The glucose from these carbohydrates is then converted to glycogen, a stored form of glucose that is used as fuel for intense muscle contractions. On that note we’d like to issue a challenge to M&F readers: eat gruel (and only gruel) for one week along with following any of our workout plans

What about protein? We’ll let you get by with a simple quinoa-based gruel (instead of the traditional oats), that will afford you slightly more protein. But again, we can’t say this enough, don’t keep up this diet for more than a week. Staying on an all-gruel diet long-term could have health risks as this plan severely lacks adequate protein (especially for someone looking to build real mass), which is vital in the body’s metabolic pathways. Another important macronutrient it’s missing is fat. Your cells, brain, skin to name a few all need quality fats to repair and replenish and keep your joints lubricated.

A Softer Version: Don’t think you can last on only gruel for a week? Tone down the challenge by incorporating a gruel meal pre-or post-workout will give you a simliar energy boost and post-workout meal.

To stay keep your budget low (around $15-20), go to a food warehouse like Costco or Sam’s club. Buying food in bulk is always cheapest.

Share Your Gruel!

If you’re brave enough to take on this diet challenge, we’d like to see it. Share your gruel pics using #GruelChallenge for a chance to be featured online.


  • 1/4 Cup Dry Quinoa
  • 1/2 Cup Water (or Milk)
  • 1 Potatoes
  • 1 Onions
  • to taste Salt/Pepper


  1. Boil quinoa (or oats) until cooked. Add in onion, corn and/or white potatoes. Add seasonings for flavor if needed
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