Supplement and Running | What you need to know

Navigating the dos and don’ts of nutrition can be difficult. Now add in considerations like exercise and fuelling for endurance events and you have yourself a puzzle.

When in doubt? Ask the experts! 

Emily Commerford is an Accredited Practising Dietitian, Accredited Sports Dietitian & Accredited Nutritionist and a keen runner. In her own words, Emily is on a mission to take the fear and confusion out of eating!

We asked Emily Commerford to answer some of our nutrition FAQs, to help you decode your diet.

What role do gels, bars & hydration play in running? When should I be adding them to my routine?

If you run short distances (<60 minute duration) it is not necessary to fuel with specialty sports foods, however some options can be useful if real food is not a practical option. For example, while running it is much easier to carry sports gels in your shorts pocket than sandwiches or bananas.

When deciding to use specialty sports foods, you first need to think about why you need them and then consider the practicalities of using them. Gels and sports drinks are required to replace glucose which can be useful before and during longer runs. Gels are small and easy to carry in your pocket, however they do need to be consumed with water. If you’re using gels, knowing where the drinking fountains are on your training route or carrying a hydration pack is helpful.

Electrolyte drinks contain sodium, potassium and other minerals lost through sweat and will help you rehydrate more efficiently than plain water. If you are a heavy sweater or if you’re running in the heat, electrolyte replacement drinks are extremely useful. Some electrolyte drinks also contain glucose so they can be used as both a carbohydrate and electrolyte supplement.

Bars vary greatly in macronutrient composition. Some runners get hungry during longer sessions and bars can be more satiating due to their solid form. Energy bars containing carbohydrate are helpful during a run, however they often contain some protein and fibre which can cause gastro intestinal upset in some athletes. While protein is important for muscle repair after exercising it does not elicit any performance benefits when taken during a run. 

Consuming gels, sports drinks and energy bars while running marathon distances or less is not essential if your goal is to simply cross the finish line, however they will help you run faster. So if you care about your time, start experimenting with carbohydrate before and during longer runs at least 6 weeks out from the race. Always remember the golden rule: NEVER try anything new on race day! It could ruin your day.


Supplements and Nutrition  

As a general rule, how many gels/ bars etc. should someone be consuming during a race by skill level/ distance etc?

As mentioned above, if you are not concerned about your time, specialty sports foods are not essential. You could definitely run a half marathon without any supplementation. Over the marathon distance you could get away with a couple of gels. If however your time is important to you, aim to consume 30-60g of carbohydrate per hour. Depending on the product, this is roughly one gel or 600ml of sports drink every 30-45 minutes.


To optimise your performance, consume the maximum amount of carbohydrate your body can tolerate without causing gut upset. The body is highly adaptable and it is possible to train your gut to take on and utilise more carbohydrate. During long training runs (>75mins) practise fuelling for race day. If you are new to specialty sports foods, try a variety of different brands and flavours as tolerance of these products is highly individual. These products are available from most running/cycling shops or large pharmacies.



Why are specialty sports foods better than just water and a couple of lollies?

It is possible to use lollies instead of gels and sports drinks, or even use a combination of options. One sports gel is roughly equivalent to 3 jelly snakes or 6 large jelly beans. It really depends on individual tolerance and preference. If you are hitting your hourly carbohydrate goals without experiencing any gut issues or flavour fatigue, then lollies will work for you. 

In colder weather rehydrating with water is generally fine unless you are a heavy sweater or lose large amounts of salt through your sweat. Sweat rates and the electrolyte composition of sweat is extremely variable from person to person. If you are a heavy sweater and feel excessively fatigued or develop headaches after harder runs, or you notice salt crystallising on your dirty running clothes, you are most likely a salty sweater. Electrolytes lost through sweat need to be replaced and in hot environments electrolyte replacement drinks are a far superior rehydration option. Rehydrating with water alone in large quantities can dilute the body’s cells, causing potentially fatal low blood sodium levels (exercise-associated hyponatraemia). This condition is generally only a risk for runners participating in longer ultra-endurance events.

 Supplements and Nutrition


What role does caffeine play in training/ race day?

It is well documented in the literature that caffeine improves endurance performance. The simulating effect of caffeine on the central nervous system reduces your perception of fatigue and allows you to sustain a faster pace for longer. The amount, mode and timing of caffeine intake required to produce these performance benefits is quite individual and depends on a number of factors including your caffeine tolerance, daily caffeine intake and the practicalities around ingesting caffeine before and during exercise. The recommended dosage can be anywhere from 1-6mg/kg of caffeine with effects lasting between 1 and 5 hours. 

The standard cup of coffee can vary in caffeine content from 60mg (1tsp of instant coffee) to 250mg (a strong espresso-style or filter coffee). You can also find sports gels that contain caffeine, generally in the vicinity of 8-40mg/gel. Some runners prefer to use caffeine strips that dissolve on your tongue (45mg/strip) or a bottle of flat coke (10mg/100ml) for a pick-me-up in the later stages of a race.

The best advice is to play around with caffeine intake during training and find the option that suits you. And of course, it is not essential. If you are allergic or sensitive to caffeine, you can finish a marathon without it!


Need help with your nutrition? Emily is here to help! Contact Melbourne Nutrition Services to arrange an appointment with Emily at

Melbourne Nutrition Services is a nutrition consulting business based in Melbourne and surrounding suburbs, founded by Accredited Practising Dietitian, Emily Commerford. Our mission is to help people nurture a positive relationship with both their bodies and the foods they love. We aim to work with our clients to help them achieve their individual goals and to take the pain, confusion and stress out of healthy eating.