Keto and CrossFit: Does It Even Work? Part 1

WHAT MAKES SOMEONE GOOD AT CROSSFIT® AND WHY YOU SHOULD CARE

Let’s take a scientific approach by analysing the “Physiological Performance Measures as Indicators of CrossFit® Performance,” study, which was done on average CrossFit athletes and measured the following:

• VO₂max test
• 3-minute all out running test (3MT)
• a Wingate anaerobic test (WAnT)
• the CrossFit total (to measure total body strength)
• the following CrossFit benchmark workouts: Fran, Grace, and Nancy.

What they found was the following:

•     For Fran – back squat strength explained 42% of the variance of performance
•     For Nancy – VO₂max explained 68% of the variance
•     For the CrossFit Total – Anaerobic peak power explained 57% of the variance

This study reveals you have to be strong, have a solid VO2max, and a solid anaerobic peak power to be a good all-around CrossFitter. The interesting takeaway here is that different benchmark WOD’s depend on different abilities, such as Nancy mostly depending on a solid VO2max.

Key Metrics for CrossFit® Success

CrossFit® has created an overall template based on “What is Fitness?” in which they provide a theoretical hierarchy for developing an athlete. See the pyramid below:

Source: Image courtesy of CrossFit Inc

Nutrition – As CrossFit’s article states: “The quality and constituent elements of an athlete’s diet influence metabolism and therefore the molecular foundations of muscle, bone, and the nervous system.”

We couldn’t agree more with this, and by the end of this series, you will understand why the ketogenic diet more than adequately checks the box.  

Metabolic Conditioning – The next most important component consists of “cardiovascular sufficiency.” This could be summarised as the health of the cardiovascular system at all levels of exercise intensity.

We will soon discuss the different energy systems and their contribution to the CrossFit® conundrum.

The additional layers of the pyramid include gymnastics, weightlifting and throwing, and sport.

Building off of what we have covered thus far, I would contend that to be successful at CrossFit® (and life) one needs to have the following attributes:

• Physical preparedness – Gymnastics, Strength, Endurance, Power, Speed, Cardiovascular Fitness
• Body composition – High lean mass and low-fat mass
• The ability to recover – Sleep, Inflammation, Oxidative Damage
• Mental health – Strong neural health and functioning
• General health and wellness – Strong physiological health markers

There are studies available for the impact that keto has on each of these categories, a couple of which will be discussed to determine their overall impact on a CrossFitter’s life.

Before this, it’s important we understand the different energy systems and their impact on CrossFit®, as this will be important in determining if keto can work for CrossFit®.

Energy System Overview

Current exercise physiology dictates that there are three predominant energy systems present in the human body:

1. Aerobic System
2. Anaerobic Lactic Acid System
3. Anaerobic Phosphocreatine System (PCr)

All three energy systems are always in constant flux, with the body drawing on the different systems in different amounts, depending on the activity. The body does not usually completely close off one system, it just downregulates and upregulates the different systems to keep everything running optimally.

Typically, the lower to moderate intensities of exercise use the Aerobic system, fuelled by mostly fat and maybe some carbohydrates.

High intensities use the Anaerobic Lactic Acid System by breaking down carbohydrates into energy.

Highest intensities are mostly fuelled by pure adenosine triphosphate (ATP) from the Anaerobic Phosphocreatine System (PCr), in which ATP (the ultimate creator of energy for the body) is directly broken down by the body to create energy.

With that information, we have now set the stage for what is important to be good at all aspects of CrossFit®.