About Lyle McDonald

Lyle McDonald+ is the author of the Ketogenic Diet as well as the Rapid Fat Loss Handbook and the Guide to Flexible Dieting. He has been interested in all aspects of human performance physiology since becoming involved in competitive sports as a teenager. Pursuing a degree in Physiological Sciences from UCLA, he has devoted nearly 20 years of his life to studying human physiology and the science, art and practice of human performance, muscle gain, fat loss and body recomposition.


Lyle has been involved, at various levels of success in competitive sports since his teens. Starting with triathlon, he spent altogether too many hours on his bike during college. Becoming involved with inline skating at the same time led him to compete for several years until he burned himself out with chronic overtraining. Many years passed until he decided to return to speed skating and move to the ice. He moved to Salt Lake City Utah to train full time at the Olympic oval, he is currently still there training with his coach Rex Albertson attempting to make the US National team or beyond.


Lyle has written for the print magazines (Flex and the now defunct Peak Training Journal), too many online sites to mention and has published 5 books on various aspects of exercise and diet.


Over the years, in addition to working with the general public, Lyle has worked primarily with endurance athletes, a few powerlifters, and some bodybuilders. Through his books, articles and his forum, he has helped thousands lose fat, gain muscle and get stronger or perform better.

Protein, Part 4: Amino Acid Kinetics and Adaptations

Dymatize Elite whey protein

The previous three parts of this article series have discussed a variety of topics related to protein and amino acids (AAs): digestion, protein quality, requirements and many others. To help readers better understand some of the mechanisms that regulate protein and AA metabolism in the body, it is necessary to develop a model of AA […]

Protein, Part 3: Individual Amino Acid Requirements

Dymatize Elite whey protein

In Part 2 of this series, the topic of protein quality was discussed, including examination of the major methods currently used to rate protein quality. For a variety of reasons, most of the currently available methods to rate proteins are deficient, especially when they are applied to an active population. Continuing with that discussion, this part of […]

Protein, Part 2: Protein Metabolism

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This article is the second in a series of articles discussion the details of protein metabolism in bodybuilders. Part 1 addressed some basic concepts and definitions regarding protein, digestion of different forms of protein as well as total protein requirements for athletes. Part 2 of this article series builds on Part 1 with a discussion of protein digestibility and […]

Protein, Part 1 – Definitions and Technical Background

Dymatize Elite whey protein

If you ask 10 bodybuilders what the most important nutrient is for putting on muscle, you will most likely get 10 identical answers (a rarity in sports nutrition). That answer is, of course: PROTEIN! Every bodybuilder knows that, no matter what else you do, if you aren’t getting enough protein, you won’t grow.

Charting Progress on the Baseline Diet Part II: Methods for Measuring Body Composition

In part 1 of this article, I made some general comments about body composition as well as discussing some of the possible methods of measuring changes in body composition.  These methods included underwater weighing, the scale, tape measures, and calipers. In the second part of this article, I’d like to discuss some other methods of measuring […]

Charting Progress on the Baseline Diet, Part 1

Calipers plus the tape measure: a winning combination

In my last two articles, I talked about how to set up a baseline diet for basic bodybuilding purposes. In this article, I would like to talk about how an individual might monitor how well (or poorly) that diet is working for them in order to determine if a change is necessary. There are a […]

The Baseline Diet, Part 2: Protein, Carbohydrates, and Fat

Bodybuilding Nutrition - Protein, Fats and Carbohydrates

Last article, I discussed three of the primary aspects of the baseline diet: meal frequency, caloric intake and water intake. To recap briefly, at a bare minimum bodybuilders (and probably everybody else for that matter) should be eating 4 times per day. Six time per day is probably closer to ideal, although this depends on […]

The Baseline Diet, Part 1: Meal Frequency, Caloric Intake and Water Intake

I’m going to start this article with a few questions. How much mass have you gained in the last few months? If you’re like the average lifter, the answer is ‘Not as much as I’d like’. Ok, next question: how much money have you spent on exotic supplements hoping they’d be the secret to freaky […]

Back to the Basics (for One Last Time)

Ask Lyle McDonald - training, nutrition, cyclical ketogenic diet, dieting

For those of you who don’t know, there are several new entries into the world of muscle magazines including a print version of Testosterone, ‘Body International’ which is being published by Sergio Oliveira, and a magazine published by the folks at Penthouse magazine called ‘Mind and Muscle Power’ (now you really can say that you […]

Ask Lyle McDonald #15

Ask Lyle McDonald - training, nutrition, cyclical ketogenic diet, dieting

Alternating Bodyopus Diet with High Calorie Diet Dear Lyle, Like everyone else my goal is to gain as much muscle as possible while maintaining a relatively low bodyfat level. I’m wondering whether you can shed some light as to whether alternating between a two week high calorie (300-500 cal/day above maintenance) isocaloric diet followed by […]