What is periodized nutrition?
Unfortunately, periodized nutrition doesn’t have one unified and clear definition. Each nutritionist and coach can interpret it differently. In general, the term “nutrition periodization” is used to describe changes in nutritional intake in response to certain periods of training. It can be as simple as eating less in the off-season to avoid uncontrollable weight gain, or carb loading before a race to maximize performance. It is a very broad definition probably because there are many nutritional approaches that can be labelled as periodized nutrition. This series should help you understand periodized nutrition and be able to implement it in your training.
Why is it important?
Research shows that manipulating carbohydrate intake and caloric intake in general can have a major impact on physiology. More and more researchers are starting to point to this in their studies. Here are a few examples to illustrate how important periodization can be.
“Periodically completing endurance training sessions with reduced carbohydrate availability modulates the activation of acute cell signalling pathways, promotes training-induced oxidative adaptations of skeletal muscle and, in some instances, improves exercise performance.” Impey (2018)
“Competitive athletes may wish to manipulate carbohydrate availability before, during, or after selected training sessions that form part of a long-term periodized training-nutrition plan to promote metabolic training adaptations that should, in theory, promote endurance-based performances.” Hawley and Burke (2010)
“Nutrition should be periodized and adapted to support changing individual goals, training levels, and requirements throughout a season and/or training cycle.” Mujika et al. (2014)
The main types of periodized nutrition
Nutrition, just like training, can be periodized in macrocycles, mesocycles, and microcycles. For example, from the macro point of view, carbohydrate intake may be much higher during the season for high-intensity training and racing and lower in pre-season when changes in body composition are the main goal. These big picture changes are relatively well-known and commonly used. What is much less known and utilized are nutritional changes in the microcycles, and even day to day, training session to training session.
These microcycle changes are mainly used to take advantage of “train low” strategies while still keeping a good proportion of “train high” sessions to maintain race intensity capacity. This approach was best summarized by the “Fuel for the work required” framework by Samuel Impey and James Morton in their 2018 study. You can read more about it in our previous article.
The researchers presented an overview of the most studied modalities that can be used to periodize carbohydrate availability throughout a week and even a single day. We will take a closer look at twice-a-day training, sleep-low train-low, and fasted training modalities in more detail later in the series.
One thing that also falls under the nutrition periodization umbrella term is race nutrition training. This approach focuses on several elements of fuelling on race day and tries to prepare your body for them in advance. It consists mainly in “train the gut” and “train hypohydrated” strategies. We will look at how to improve your tolerance to high quantity of carbohydrate and how to perform in suboptimal hydration towards the end of this series. Next article will focus on macro- and mesocycles in nutrition.