Experts and muscleheads alike say to build a lean, muscular body you must follow three rules:

  1. eat a lot of protein
  2. have a variety of nutrient-dense foods
  3. eat every three to four hours

We’re told that trying to get big and strong without this trifecta is a waste of time. Especially if we ignore that last rule. But some have questioned whether meal frequency is really that important. Can you actually build muscle and lose fat faster by going long stretches without eating?

Those in the intermittent fasting (IF) movement think so.

It sounds counter-intuitive for building muscle, but the hardest of the hardcore "fasters" aren’t simply skipping meals. They’re combining periods of fasting with calculated high protein re-feeding — and are getting bigger and leaner.

By not having to eat so often, they’re enjoying less meal-time hassle, and all the while thumbing their noses at the so-called experts.

Dr. John Berardi is one of those experts.

For years he championed six-meals-a-day, and got awesome results with thousands of clients. But Berardi is also a scientist, and at the heart of the scientific method is objectivity. If new information comes to light that could improve upon current practices, it’s up to the scientists to swallow their pride and revisit their conclusions.

Sadly, many don’t. They say they want to see more or better research first, a fancy way of saying they’d rather hole up in their ivory tower than suffer the humiliation of admitting they may be wrong. So, Berardi took a different route. He jumped into the fasting fire and used his own body as a guinea pig for six different fasting protocols over an eight-month period. And like any good scientist, he documented everything along the way. In fact, he even published an entirely free e-book detailing all of his experiments and results, called Experiments with Intermittent Fasting. I know because I co-authored it with him. So, is intermittent fasting (IF) a crock of crap? Or is it the future of high performance eating? I talked with JB to get his thoughts.

Nate: Fasting? Are you just trying to capitalize on the IF hype?

Dr. Berardi: Not at all. Frankly, I’m exposing myself to serious scrutiny by even entertaining IF — after all, it’s counter to what a large part of my career has been built on. I’ve transformed a lot of bodies through a frequent feeding approach. But the benefits I’ve been reading, both in the message boards and in the literature, are intriguing. The more I looked at IF, the more I saw it as something that could help a lot of people, especially those who find frequent feedings a challenge. But before I endorsed it, I wanted to test it myself to see what kinds of physiological and psychological changes would come from it.

Nate Green: So what were your results?

Dr Berardi: Well, some really cool things happened. Getting into everything is beyond the scope of this interview, since I collected a hell-uva lot of measures. But, to sum up, I lost about 20 pounds of fat, while preserving most of my lean mass. I went from a fairly lean 10 percent body fat to a very lean 4 percent (as measured by ultrasound).

Here are some progress photos:

Nate: Wow. You’re diced! But you’re always pretty lean, JB. Did you test drive IF with any of your clients?

Dr Berardi: Yep, I put a few of my clients to the test, but not just with folks looking to lose weight. I used IF with a guy who wanted to gain weight – and he gained 20 pounds of quality lean mass in a matter of months.

Nate: 20 pounds of mass gained by not eating?

Dr Berardi: Not exactly. I used a bunch of different fasting ideas in my experiments, all of which I detail in a free e-book I just published called Experiments with Intermittent Fasting – more on that later. Some of the experiments involved strategic daily fasts combined with short intense periods of post workout overfeeding. Other experiments used one weekly-full day fast combined with four days of weekly overfeeding and two days of maintenance eating. In the end, whether the test subjects wanted to lose weight or gain weight, we used strategic periods of under and overfeeding to accomplish those goals. In the case of that client who gained 20 pounds, he fasted one full day a week (Sunday). He ate at maintenance three days of the week (on conditioning days). And he ate a huge surplus three days of the week (on strength training days). And not only did he gain 20 pounds, he improved every tested performance indicator – aerobic, anaerobic, and strength/power.

Nate: Cool, what about getting lean? What exactly have you been doing personally?

Dr Berardi: Well, I haven’t been doing one plan so much as I’ve been experimenting with a number of different intermittent fasting ideas. During the last eight months, I’ve played around with at least eight different IF protocols. Some of them worked okay, some were flops. One in particular was so bad I thought it would cost me my marriage! This included two full-day fasts each week. But, another worked as good or better than any other dietary protocol I’ve ever tried. I actually gained more lean body mass than I wanted. I was trying to lose weight and had to cut it short. This included fasting for 16 hours each day, followed by a fasted training session, and then three huge meals during the eight hours post-workout. Again, the free e-book goes into all the details. I outline all the protocols. And I kept meticulous notes on everything from scale weight, body-fat percentage, and blood/hormonal markers, to lifestyle markers like energy levels, and cognition. What can I say? I’m a scientist.

Nate: I’d still be kind of afraid of what fasting would do to my muscle mass.

Dr Berardi: Let me guess: you assume because you got big and strong by eating lots of food, frequently throughout the day, fasting would do the opposite? You’d get smaller and weaker?

Nate: Well, yeah.

Dr Berardi: Funny, it doesn’t really work that way at all. Not if you do it right.

Nate: Okay, so how does one “do it right?”

Dr Berardi: Again, depending on the goal, there are different fasting protocols, from weekly 24-hour fasts to twice-a-week fasts to daily fasts lasting anywhere from 16-20 hours. I get into them all in the book. But let’s just say more is not always better. It’s important to strike a delicate balance between undereating and overeating to stimulate the fat burning process while also seeing hormonal surges that help with recovery and muscle-building. For example, growth hormone is released in tremendous quantities during extended fasts. Of course, daily and weekly calorie intake is still important. You can’t grow if you’re in a calorie deficit, regardless of whether you’re eating 2 meals a day or 6 meals a day. Likewise, you can’t lose fat if you’re not in a calorie deficit. Also, there are certain supplements that help mitigate hunger and preserve lean body mass. Of course, by doing so it may no longer be “fasting” in the purest sense of the word, but I’m interested in results, not semantics. And a small handful of supplements definitely help deliver better results.

Nate: So competitive bodybuilders could try this?

Dr Berardi: It depends. You don’t just throw intermittent fasting into the mix without considering everything. The program has to represent an internally consistent system. The parts all have to fit together. If they don’t, it’s not going to work. For example, during high volume training, intermittent fasting would probably be a mistake. Further, I also find that IF works better with calorie and carb cycling during the training cycle. Again, everything has to fit together for this to work.

Nate: So, six meals-a-day is so 2010?

Dr Berardi: No way! IF works, but people have been getting and staying in awesome shape for decades without it. So I think more frequent eating still has a great place in performance nutrition. Whether to eat frequently or infrequently, to fast or not to fast; it’s about finding what works best for your own body and your own preferences. In my case, I found that IF didn’t accelerate my fat loss. But it did make it much easier to maintain a low body fat percentage. I’ve been able to maintain my 20-pound weight loss for five months. And I even outline some hybrid ideas where I use fasting some days and more frequent eating the others.

Nate: How can people learn more?

Dr Berardi: As you know, I just published an absolutely free book on the subject called Experiments with Intermittent Fasting. I cover everything, including details of my training programs and my exact eating plans for all the IF protocols I tried. You can literally do what I did step-by-step, although if you’re smart, you’ll skip my screw-ups and go straight to my successes. It’s 100% hosted on-line so anyone interested in more can pop over to the site and read the entire thing right now, for free, without having to give their email address or anything.

About Dr Berardi

John Berardi received his PhD in Exercise Physiology and Nutrient Biochemistry at the University of Western Ontario, Canada. He’s currently an Adjunct Professor at Eastern Michigan University and the University of Texas. As an elite nutrition coach and exercise physiologist, Dr. Berardi has coached hundreds of elite amateur and professional athletes. In fact, in the last two Winter Olympics alone, his athletes collected over 25 medals, 12 of them gold. He’s also a high performance consultant with Nike. Further, for the last 4 years, Dr. Berardi has acted as the director of the world’s largest body transformation project. This one-of-a- kind fat loss coaching program has produced more total weight loss than all 11 seasons of The Biggest Loser combined.