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Author: Dr Matthew Campbell | PhD ACSM-CEP MIFST RNutr FHEA BSc hons.
Read time: 5-10 minutes
The two main nutritional considerations for football are eating enough carbohydrate and drinking enough fluid. Whereas this is important in the time leading up to a match, it is also important to take on additional energy and fluids during the match.
What should I eat during exercise?
Research studies consistently show performance benefits during simulated football matches when carbohydrate is consumed during exercise at a rate of approximately 30-60 grams per hour (41-44), or up to 60 grams before each half (45). The 30-60 grams of carbohydrate can be taken after warm-up and again at half-time to meet these guidelines. Consuming 30-60 grams of carbohydrate in the form of food such as energy bars can sometimes be difficult and result in stomach upset. However, carbohydrate-based drinks and gels can often minimise potential stomach issues – it will also help with hydration as discussed below. A major consideration about carbohydrate intake immediately before and during exercise will be managing the impact of this on blood glucose levels. You will need to make a judgement about how best to manage your insulin dose to minimise blood glucose spikes, and, to ensure that you do not have excessive insulin ‘on-board’ during the game which could cause hypoglycaemia – read this article about insulin dosing strategies for exercise.
What should I do if I struggle to manage blood glucose levels when consuming carbohydrate during a match?
If controlling blood glucose levels is difficult for you during football and you’re worried that eating carbohydrate might make this worse there is another, rather strange, but very special technique to try – carbohydrate mouth rinsing. The body is equipped with specialised receptors within the mouth that can detect carbohydrate. This detection of carbohydrates sends signals to the brain that reduce the perception of effort1. Carbohydrate mouth rinsing, which involves rinsing, but not swallowing, the mouth with a carbohydrate-based solution – like you would with mouthwash – has been shown to increase self-paced jogging speed with likely benefits in sprint performance during intermittent types of exercise2,3. There is limited research investigating this technique within applied football settings, although it is logical to think that this strategy could be effective. Using the carbohydrate mouth rinsing technique during breaks in match play (like half-time periods, extra-time, injury stoppages, and medical breaks) could potentially improve performance in situations where eating carbohydrate is either impractical or likely to cause stomach upset or unwanted blood glucose spikes. If your glucose levels tend to be stable during the match and managing hyperglycaemia isn’t too much of an issue for you, then you can combine mouth-rinsing and swallowing. Swallowing a carbohydrate-based drink following a short (approximately 5 second) mouth rinse allows for both the activation of brain signals to reduce perceived effort and will provide extra fuel to the body. This type of strategy might be particularly effective towards the end of games where fatigue may start to impact decisions making processes.
How much fluid should I drink during a match?
Although you can buy isotonic sports drinks, you can also make your own by simply adding a little salt to some squash. It is well established that dehydration impairs both physical and mental performance4,5, although some people are more sensitive to the effects of dehydration than others. The amount of fluid your body requires during a match is determined largely by the amount that you sweat, which, differs from one person to the next, and is dependent on the intensity of exercise, external factors like humidity and temperature, and how well you are acclimatised to the conditions6. Sweat rates in male footballers have previously been reported to range from 0.5-2.5 litres per hour7-9, whereas lower values are generally reported in female players largely because women tend to be smaller than men and expend less energy during exercise10-12. As well as water, sweat also contains electrolytes – primarily sodium (salt) – the amounts of which, again vary from person to person9. As a general guide, footballers should aim to drink sufficient fluids to avoid a reduction of 2-3% of pre-match body weight during a match13 and avoiding gains in body weight to prevent over hydration. As a starting point, measure your weight before and after a match (or even better during training), if you have lost more than 2-3% of your starting body weight then you need to drink more during matches when you can!
If you are interested in learning how to improve managing your type 1 diabetes around exercise book a consultation with the author, Dr Matthew Campbell: email@example.com
Matthew is an internationally recognised research scientist specialising in exercise, diet, and type 1 diabetes. He also provides consultancy and diabetes coaching to people living with type 1 diabetes and those that support them.
Matthew has a PhD in nutrition and exercise metabolism, is author to over 150 research publications, and holds honorary titles with the University of Cambridge and University of Leeds. He is a certified clinical exercise physiologist accredited by the American College of Sports Medicine, a registered nutritionist, and a member of the Institute of Food Science and Technology. He also provides consultancy to professional bodies and professional athletes including NHS England, the World Health Organisation, and TeamGB.
If you are interested in learning how to improve your type 1 diabetes management, contact Matthew at: firstname.lastname@example.org
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