My Crazy Weight Gain Experiment

Crazy Weight Gain Experiment
Crazy Weight Gain Experiment

In November 2019, I read a very interesting and humorous book about a crazy weight gain experiment that took place back in the early 2000’s by a young Canadian man. For one month, he ate a major surplus of food and worked out like a beast. He gained quite a bit of weight, most of which was muscle and not fat.

He did this program with an elite nutritionist and elite trainer as part of his team, so he was supervised throughout the month. Moreover, he documented everything. As I said above, I found the book to be very interesting, entertaining and intriguing.

So intriguing, in fact, that I thought to myself, perhaps I should do this same experiment. After all, the holidays were coming up and most people tend to indulge and eat a bit more over the holiday season. As such, the timing seemed right to me. And thus, I pulled the trigger on this crazy idea!

What follows below are some of the details and the results of “My Crazy Weight Gain Experiment.”


I started the experiment on December 4, 2019 and concluded on December 31, 2019.


I coached myself throughout the experiment. I did not hire a professional nutritionist, since I am a Certified Nutritionist and Precision Nutrition Coach.  Nor did I hire a professional trainer, as I am also a Certified Personal Trainer. I followed the eating plan in the book with just a few tweaks; simply to right-size the diet to my body weight and height. And I followed the prescribed workouts in the book pretty close to exact. They were quite challenging. It was a tough but rewarding month.


My normal daily calorie intake for maintenance is around 2,650 calories. This is a bit higher than most “textbook calculations” derive for my size/weight, but based on personal experience over many years, I know this to be quite accurate. At 2,650 calories per day, I do not gain or lose weight.

During the month of December, I was eating between 3,800 – 4,000 calories per day! That represents an approximate 45% increase in daily calories, which is a lot!  However, with only one exception (Christmas Day), the quality of the food was extremely high and very nutrient-dense. In other words, I was not eating pizza, ice cream, cake and pastries. I was eating loads of lean meats, vegetables, fruit, potatoes, nuts and a little bit of whole grains. It was a super high nutrient dense diet.

I ate this was for 6 days each week, and then 1 day per week, I fasted for 20 – 22 hours, followed by a small, light meal of protein and veggies. I thought that the fasting would be terrible, but it wasn’t. As it turns out, the “fear” of being hungry is clearly all in the mind. In other words, it’s all psychological. The body can handle fasting very well and I personally had no issues.

I did experience two notable issues with the diet. One was early on (in the first few days) and the second was around the middle of the month. Issue #1 was adjusting to all of the extra calories during the first week. I found it very difficult to stuff myself to the point of being over-full, just to meet the target numbers. It was not until about day 4 that my stomach/body adjusted. There were some unpleasant side effects, but nothing serious.

Issue #2, in the middle of the month, turned out to be quite a surprise.  I do not often eat any grains, because they are not terribly nutrient-dense.  I’m not saying that grains are unhealthy, but that they pale in comparison to meats, nuts, veggies, and fruits from nutrient density perspective.  In order to get to the target calories, I needed to consume some small amount of grains.  As grains tend to be a comfort food for many (myself included), this was awesome at first.  But by the middle of the month, I was just plain sick and tired of grains, and I had to stop eating them.  I did not see that coming.


As noted above, the workouts were tough. I was working out 6 days a week with tremendous intensity and at a high volume for 4 of the 6 days. I rested/recovered on my fasting day. Here is the breakdown:

  • 2 days per week: CrossFit
  • 3 days a week: Lifting with an intense metabolic conditioning finisher
  • 1 day per week: All-out sprints, followed by highly metabolic weight movements.

These workouts were challenging and very draining. I absolutely loved every minute!


What do you think happened when I purposefully over ate for a full month? Are you guessing that I gained a lot of weight and got fat? That would be a logical guess and I’ll tell you why.

The guy in the book was a young male, in his 20’s. I am not in my 20’s but rather in my 50’s. I have a genetic pre-disposition to developing type II diabetes, and as such, one of my only health issues is managing my blood sugar. This means that I am not as insulin sensitive as a healthy dude in his 20’s.

So, logically, the best guess is that I would put on a lot of weight as body fat. Here are my results, including body metrics and physical tests:

    • Metric               12/4/19            12/31/19
    • Body Weight      169.4                170.6
    • Body Fat %         16.0%               15.8%
    • Waist                   33.25                34.0
    • Thigh                   22.0                  21.0
    • Chest                  41.0                   42.0
    • Deadlift (1RM)     355                    375
    • Bench Press (3RM) 155                170
    • Broad Jump*          72.25”             76.25”
      *Average of 3 attempts


Are you surprised? I gained 1.2 lbs. of body weight over 28 days of MAJOR over-eating.  In addition, my body fat % decreased! So what happened?

Here are my thoughts:

  • First, as I mentioned above, with the exception of Christmas Day, when I enjoyed quite a few sweets, I ate an extremely healthy and nutrient dense diet during the month of December. I was not cheating. I was just plain eating a ton of really, good, healthy food.
  • Second, these workouts were really intense. I was really pushing it and while training is NEVER as important as good nutrition, these workouts certainly helped me to keep the excess calories from turning into body fat.
  • Several other observations: while my overall body fat % decreased slightly, it shifted its distribution within my body. I gained some fat in my abdomen, but reduced fat everywhere else. And all of my fitness tests improved, which I was really stoked about.
    • While I wasn’t thrilled with the increase in the belly fat, I knew that it was transient, so I’m not at all worried about that. If there were one thing that I was disappointed with, it would be the fact that my quads lost size. I attribute that to the intense metabolic conditioning workouts, which were highly leg-intensive.

Wow! What an experiment. I’ll say this; it was a bit scary and daunting at first. And as much as it sounds great to purposefully over eat, that was really, really difficult at first.

Would I do this again? No – at least not exactly as laid out in the book. If I were to do something akin to this again, and perhaps I will, I would do less calories and I would cut out some of the metabolic conditioning. I am in favor of the high calories, but I would modulate it a bit and I would ramp up to a target number, rather than changing all at once.

I think the best thing about this experiment is what I learned about myself, but I will also say that there is a lesson here for everybody. Over-eating is not automatically a formula for gaining weight and/or body fat. This is exactly what nearly everybody thinks, and frankly, that is wrong. If you eat a healthy nutrient-dense diet, then it is highly unlikely that you will gain weight. I can say that with authority, because I just proved it!

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