How to Periodise Nutrition Between Training Periods and Holidays

Nutrition Periodising

When it comes to nutrition and diet for athletes there’s a world of information available that can quickly become confusing. 

If you’re spending long periods of the year training and then having downtime during holidays, deciding what foods to eat and in what quantities for performance and health can be a challenge.

This guide aims to simplify periodising nutrition and provide general principles for healthy eating, whether you’re deep in a training block or putting your feet up on the beach. 

What does periodising my nutrition between training and holidays mean?

Periodising your nutrition between training and the off-season generally means adjusting what you are eating to the amount of exercise you’re undertaking at different times of the year.

The more you train, the more you need to fuel, so in the simplest terms this might mean larger portion sizes or more frequent meals when training. However, for some athletes it also might not mean much change.

Firstly, if you’re completing well-fuelled (rather than fasted) training sessions, where plenty of calories are consumed during the exercise, quantities at mealtimes may not need adjusting significantly. 

Secondly, you could be more relaxed around nutrition in the off-season and content to eat a similar quantity of food, even without the volume of exercise. While this may lead you to gain weight, often endurance athletes err towards being “too light” during the racing season, and consuming more could be beneficial for all-round health. 

How should I periodise my nutrition between training and the off season?

Whether training or during holidays, athletes will gain the most benefit, physically, mentally and emotionally, by aiming for a healthy, balanced diet. This can help with staying energised, reducing cravings, improving mood and minimising the chances of illness. 

However, a balanced diet, particularly in terms of quantity, also needs to take into account your lifestyle and level of exercise.

If you want to take a scientific approach, you could use a fitness tracker to record how many calories you burn on a daily basis when in light, moderate and heavy training, and rest days. If you also measured your caloric intake by understanding how man calories were in everything you ate and drank, you could then gauge whether to eat more or less. 

However, few professional athletes follow this approach, and it presents significant risks. As well as being time consuming with inherent inaccuracies, more concerning is the reductionist nature of a ‘calories in versus calories out’ approach, which can form unnecessary guilt complexes around eating.

A better approach might be simply being mindful of overall consumption, trying to be in tune with your body and deploying a certain level of trial and error to find what works best.

Some nutritionists recommend an 80:20 approach, where 80% of the time you’re eating fresh, unprocessed ‘healthy’ food, and 20% of the time you give yourself more license for the occasional pizza.

Should my racing weight and off-season weight be different?

This is a much-debated issue that comes down to personal choice. Those who gain and lose weight more quickly may find that a difference between racing weight for endurance events and off-season weight comes more naturally. Others won’t see a marked difference in their weight at any time of year.

There is also an argument to say that a healthy, sustainable weight and race weight should be the same thing – and the benefits of losing extra kilogrammes in the hunt for more speed (particularly with runners and cyclists) is more than off-set by the risk of injury and illness. 

For most amateur athletes this is likely to hold true, with consistency of training and staying injury-free probably the No 1 indicator of successful performance. Elite athletes, who rely on performance to make a living, may be tempted to look more closely at body composition for short periods to gain an edge. However, it’s worth noting they should have expert support teams around them for guidance.

Perhaps a good example is Ironman triathlon. Look at the latter part of the marathon and you’ll see many athletes whose form has completely collapsed. For longer distance events being strong and powerful to retain form is more critical than simply being as lean as possible – and to achieve both is a delicate balance. The point being, having one more potato probably won’t harm your chances. Having one too few might.

What food should I eat to boost my immune system when training?

The body can become depleted through training and we can be more susceptible to bacterial infections and viruses. Thankfully, there are plenty of foods that can give your immune system a boost. These include:

  • Oily fish
  • Organic, grass-fed meat
  • Broccoli
  • Sweet potatoes
  • Spinach, kale and dark leafy vegetables
  • Fermented foods such as kefir, kombucha, sauerkraut 
  • Nuts and seeds
  • Red berries
  • Ginger
  • Garlic
  • Turmeric
  • Dark chocolate

Are there any foods I should eat more of when I’m training?

You need to eat to suit your calorific demands, so if you are consuming a balanced diet anyway, just eating more of the same is a straightforward solution.

With more muscle breakdown through training, try to make sure you are getting enough good quality protein. This can be more easily achieved if you’re a meat-eater, so vegetarians may need to look for lentils, pulses, soya and dairy products (if they’re not vegan) to get a good mix. You can also be more rundown so food such as garlic and ginger (see list above) that help keep your immune system robust are recommended.

There are also a couple of watchouts. When training, you are likely to build more of an appetite and be hungry more often. This can mean a craving for energy, which leads many of us – particularly those with a sweet tooth – to reach for easily digestible carbs in the form of refined sugars. Ie. sweets, cakes and chocolate.

To prevent refined carbohydrates making up a higher percentage of your diet than is healthy, food planning is the key. If you prepare healthier post-training snacks and meals ready in advance, you can simply take them from the fridge or zap them on the hob, or in the oven or microwave and maintain a healthy balanced diet.

10 Golden rules for good nutrition

  1. Don’t set too many rules! This can lead to a reductionist approach to your diet, omitting key food groups and losing the joy of eating.
  2. Variety is key. Different types of food help cover the key macro and micronutrients.
  3. Add colour. A rainbow on the plate rather than a plate of beige is a good rule of thumb for a healthier diet.
  4. Look for unprocessed. The closer the foodstuff is to its origin, the less processing it has had – and the fewer additives will be included.
  5. Food provenance. Understand where your food has come from, for example, whether it’s local and organic. Less travel probably equals better quality.
  6. Don’t villainise salt. Salt isn’t always bad for athletes. In fact, it’s essential for our body, and we lose it through sweat when training.
  7. Low fat doesn’t often mean healthier. Food marketed as low fat can often be heavily processed and high in sugars and additives. As with salt, fat is a cornerstone of the diet and can help satiate you, so your less likely to reach for refined sugars.
  8. Treats are ok. If you’re training hard, having the occasional sweet treat isn’t a poor choice. If concerned, eat sweet food around mealtimes with other foods, so it’s not such a sugar rush to your system.
  9. Eat enough. Even if you are following a strict diet or trying to eat clean, as an athlete in training you should make sure you eat enough to fuel your sessions and lifestyle. Otherwise risks of injury and illness rise significantly.  
  10. Be wary of iron deficiency. Particularly if you’re a vegetarian or vegan athlete that avoids meat. Female athletes may be more susceptible to anaemia.
  11. Don’t overcomplicate it. Getting too hung up on what you’re eating, how much and when can add unnecessary additional stress.


Should I try a low carb, high fat diet to improve my performance?

Different diets for endurance athletes have become more en vogue over the years, and the low carb, high fat (LCHF) approach is popular with those looking to become more fat-adapted (using fat as an energy source) or even reverse the effects of diet-related Type 2 diabetes.

The LCHF may work well for some athletes and not for others. However, if you wish to attempt it, it’s advisable to do your research first and make sure that with a more restrictive diet you are not cutting out any essential nutrients. If you are training, you also should make sure you are eating enough quantity having reduced carbohydrates, which can otherwise make up around half to two-thirds of a typical diet.

How many calories should an Ironman triathlete eat when training?

It depends on the duration and intensity of sessions. For some guidance, the 2021 Ironman 70.3 champion Lucy Charles-Barclay has estimated she burns around 3,500 calories in a regular training day. The general NHS guidelines for calorie intake are around 2,000 for women and 2,500 for men for the typical lifestyle (non-triathlete). While amateurs will be unlikely to be training as much as Charles-Barclay, it’s still an indication that you may need to consume as much as 50 per cent more than the regular diet when training.

What is a healthy, balanced diet?

A healthy balanced diet is a varied diet covering all the major food groups, protein, fats and carbohydrates, and essential vitamins and minerals. Generally, the diet is better if the food consumed is fresh and unprocessed.

Should I add extra salt to my food?

There is a lot of health messaging around excess salt in the western diet leading to high blood pressure, which can lead to heart and kidney problems among other issues. 

Much of this salt intake comes from highly processed foods, so eating fresh produce is a way to cut back. Unless specifically advised otherwise for a medical condition, athletes shouldn’t be scared of adding salt to their food as it serves a vital function in balancing fluids in the blood, maintaining healthy blood pressure, and is essential for nerve and muscle function. 

Athletes sweat constantly when exercising and depending on sweat rate and sodium-content will lose more salt than a sedentary individual. Adding extra salt to a fresh food could also be a positive step to ward off cramps, but the science is less proven here.

Should I drink alcohol during training or holidays?

There’s no getting around it, alcohol will have a negative effect on performance, especially if consumed in large quantities. Drinks such as red wine have some purported health benefits such as antioxidants, but alcohol is a diuretic, which can lead you to becoming dehydrated. Alcohol can also prevent efficient healing of the muscles after exercise. 

This may hint towards only consuming alcohol on holidays and not while training, but it is personal choice. If you are concerned but want a drink, consider having alcohol at mealtimes only. Its negative effects are slightly mitigated when consumed with food. 

Sign up now