Fast Running

Sugar for Runners: Good or Bad?

Everyone has heard that too much sugar is bad for you, but is this message a ‘one size fits all?’ How does this apply to runners?

How many of you have tried to ‘give up sugar’ only to succumb to your sugar cravings mid-afternoon? Some of this is human behaviour – tell someone they can’t have something and it sets up “deprivation mentality” so they instantly want it.

However, some of this ‘need’ for sugar is actually physiological. Don’t forget if you are training hard, with a percentage of your training at high intensity, then the body is going to need a readily available source of energy to fuel this work; glucose is the preferred source and sugar provides an instant source. In addition, our brain uses 120g of glucose a day to support and control all the metabolic processes that occur within the body.

The SACN report developed some national guidelines a few years ago which recommended that “added” sugar should make up no more than 5% of your total energy intake and a maximum of 30g a day. This includes white table sugar (sucrose), brown sugar, honey, maple syrup, agave syrup, coconut sugar and high fructose corn syrup.

So, if you are consuming 3000 Kcals a day then your total amount of extrinsic sugar should be no more than 150Kcals or seven teaspoons. This excludes sugar naturally found in fruit or milk, (lactose), known as intrinsic sugar.

While national guidelines are necessary, it is important to highlight that firstly they are “guidelines” and secondly, while they encompass a message for the general population, not everything is relevant to those who run and train regularly (four or more times) each week and even more so for those who train more than seven times.

In general, within the running population, it is advisable to look at the balance of sugar intake over the course of seven to ten days. No food should be demonised and while I’m not advocating eating large quantities of “added” sugar, at times it can be useful for runners.

Around high-intensity training days, easily absorbed carbohydrates such as sugar; whether that be honey on toast, cereal bars, diluted orange juice or a sports gel are effective ways to top up energy stores for your training session.

Similarly, after high-intensity training sessions, in order to ensure runners replenish glycogen stores as quickly as possible, easily absorbed carbohydrates such as flavoured milk are the best source.

Don’t rely on sugar as your only energy source
That said, runners should not rely on sugar as their only energy source. Try to encompass some of the following strategies:

Alternatives to energy gels
Trying to find alternatives to energy gels and drinks for training is more tricky –the majority of “natural” alternatives still use honey, agave, rice or date syrup – regardless of what you have heard, these are all still sugar and utilised by the body in exactly the same way as sucrose or table sugar.

Some suggestions include:


About the Author
Renee McGregor RD SENr is a Performance Dietitian and author, who works with elite athletes, coaches and sport science teams to provide nutritional strategies to enhance performance and manage eating disorders. She is the author of Training Food, Fast Fuel books and Orthorexia, and soon to be released Healthy eating goes bad.