Research in conventional sports nutrition has started to look at the effect of low-carbohydrate availability as a way to promote training adaptations relating to increased mitochondrial biogenesis and oxidative metabolism.

However, most of these studies have reported no improvements with regard to performance.

This has led to the notion of nutrition periodisation, namely combining low-carbohydrate availability sessions for metabolic adaptations with high-carbohydrate sessions to maintain and improve performance quality. A periodised approach should have a purpose and be carefully planned according to an athlete’s day-to-day training loads. The timing of nutrition moreover has an important impact on adaptations to training and recovery from competition.

Different periodised methods can be used depending on an athlete’s specific goals. Jeukendrup recently published a really nice review outlining the different methods that include the “manipulation of nutrient availability before, during and after training, but could also include practices that prepare other organs for competition through nutritional manipulation (e.g. improving stomach comfort by regularly drinking large volumes) (1).”

'Train low' is one of the most common methods and it describes training with low-carbohydrate availability aimed at stimulating the expression of relevant genes, including those that support mitochondrial biogenesis or enhanced oxidative metabolism through the activation of regulatory factors, such as AMP-activated protein kinase (AMPK). Low-carbohydrate availability has the reciprocal effect of increasing circulating free fatty acids and/or increased muscle triglyceride levels that enhance an athlete’s ability to oxidise fats at a higher workload, which, in turn, has a muscle glycogen-sparing effect.

Different strategies can be used to employ the ‘train low’ method and the correct one depends on an athlete’s goals, as described by Jeukendrup (1):

  • ‐ Training twice a day: limiting carbohydrate intake between sessions with the aim of the first training session lowering muscle glycogen levels for the second training session.
  • ‐ Training in a fasted state: training after waking with no food intake in a low liver glycogen state.
  • ‐ Low-carbohydrate availability during recovery: not consuming any carbohydrates after a training session.
  • ‐ Sleep low: training late and not consuming any carbohydrates before bed. Muscle and liver glycogen will be low.
  • ‐ Training with low carbohydrate availability: no ingestion of carbohydrate during a prolonged training session.
  • ‐ Low-carbohydrate high-fat diet: long-term approach of maintaining low-carbohydrate stores with the upregulation of enzymes involved in fat oxidation.

The ‘train high’ method describes training with high carbohydrate availability, aimed at maintaining training quality and reducing the onset of fatigue. This can be done by consuming carbohydrates before a training session to increase muscle and liver glycogen levels.

Training the gut is another method of periodisation aimed at reducing gastrointestinal symptoms, that can negatively affect an athlete’s performance. This is achieved by improving gut adaptations that enhance nutrient or fluid absorption. Examples of strategies to train the gut, as described by Jeukendrup, include (1):

  • ‐ Increasing the amount of food intake or regularly drinking large volumes with or without exercise to promote stomach comfort.
  • ‐ Repeating the consumption of meals to improve gastric emptying.
  • ‐ Increasing daily carbohydrate intake before or during exercise to improve the gut’s absorption capacity.
  • ‐ Training the athlete’s competition nutrition strategy during training sessions.

Another aspect of periodised nutrition is to train in a dehydrated state for an athlete to become familiarised with dehydration in case this occurs during competition. Finally, there are many supplements that can be used in a periodised fashion to enhance training adaptations. For example, leucine is an essential amino acid that stimulates muscle protein synthesis and would therefore benefit an athlete wanting to gain muscle mass and improve strength.

Nutrition should be periodised in the same way as training. But it shouldn’t stop there: athletes would benefit more from a periodised nutrition approach if sport nutritionists also took food quality into account. And that is where integrative sports nutrition comes into play. Go the extra mile for your athletes by bridging the gap between conventional sports nutrition and integrative sports nutrition.


Jeukendrup (2017). Periodized Nutrition for Athletes. Sports Medicine. 47, 51-53.