For long runs and race rehearsal, plan carbohydrate and fluid intake using labelled amounts rather than treating a sparkling mixer as a complete fuelling drink. World Athletics lists up to 90 g of carbohydrate per hour for events lasting more than 2.5 hours; soda water supplies no carbohydrate on the cited Schweppes label, while tonic values vary by product. If you want fizz during a run, try the exact drink and amount in training first.
For a long run or race rehearsal, you need to know what the whole plan provides per hour. World Athletics lists carbohydrate drinks, gels and confectionery among the options for events lasting more than 2.5 hours; a mixer label alone cannot tell you what the combined plan delivers.
For a sparkling drink around easier training or at a social occasion, it helps to distinguish soda water from sweetened tonic. Coca-Cola Great Britain labels Schweppes Soda Water at 0 g carbohydrate per 100 ml; Fentimans labels its Premium Indian Tonic Water at 4.4 g per 100 ml.
Try the exact drink at the intended amount and running intensity before relying on it in a key session. A study published in the International Journal of Sport Nutrition found no significant average effect of carbonation on the measures it tested, but that result cannot establish how any individual runner will respond.
Consider when: You are planning carbohydrate intake for a long run, race rehearsal or marathon. World Athletics lists drinks alongside gels and confectionery as delivery options for events lasting more than 2.5 hours.
Trade-off: You still need to calculate what the combined servings deliver per hour and rehearse the amounts you intend to use.
Consider when: You want fizz without asking the drink to supply carbohydrate fuel, such as with food after an easy run.
Trade-off: Coca-Cola Great Britain labels Schweppes Soda Water at 0 g carbohydrate per 100 ml, so it cannot contribute to a carbohydrate target.
Consider when: Taste and a sparkling serve are the priority, rather than a complete marathon-fuelling drink.
Trade-off: Sweetened and light tonics have different label values; any carbohydrate they provide must be counted alongside the rest of your plan.
| Priority | What to check | Your needs |
|---|---|---|
| Carbohydrate delivery | Read grams per 100 ml and per container. Add the drink, food and gels you plan to consume in an hour; check that the amount is practical to carry or obtain. | I need to know what my whole fuelling plan delivers per hour, not just whether one drink contains sugar. World Athletics lists up to 90 g of carbohydrate per hour for events lasting more than 2.5 hours. |
| Fluid and salt | Check container size and labelled salt or sodium. Plan when and how much you will drink rather than using carbonation as a sign of suitability. | My drinking plan needs to fit the run and its conditions. Runner observations published in the International Journal of Sport Nutrition and Exercise Metabolism found a wide range of sweat losses and required drinking rates. |
| Comfort with fizz | Try the exact drink and amount during comparable training. Assess it alongside the rest of your food and drink intake. | If I want a carbonated drink during a run, I need to know whether I can comfortably consume my planned amount. |
| Exact variant | Compare carbohydrate, sugars and salt per 100 ml. Read the ingredients, including quinine or sweeteners where relevant, and check the pack size. | A soda water, regular tonic and light tonic may look similar in a glass, but I need the figures from the pack I will actually use. |
Coca-Cola Great Britain lists 0 g carbohydrate per 100 ml for Schweppes Soda Water, while Fentimans lists 4.4 g per 100 ml for its Premium Indian Tonic Water. Fizz alone tells you nothing about carbohydrate delivery.
Set out the carbohydrate you plan to consume per hour, then count the contribution from the exact drink and any food or gels.
The International Association of Athletics Federations’ 2011 nutrition guide describes sports drinks as typically containing 4–8 g carbohydrate per 100 ml. A tonic’s carbohydrate figure alone does not establish its place in a complete drinking and fuelling plan.
Check the tonic’s serving size, carbohydrate, salt and ingredients, then assess it alongside everything else you intend to consume.
A study published in the International Journal of Sport Nutrition found no significant average disadvantage under its tested conditions, but it cannot predict comfort with your drink, amount or pace.
Try the exact drink during a comparable training run. If it is uncomfortable or makes your planned intake impractical, use an alternative you have already rehearsed.
Product-specific labels show different carbohydrate amounts for soda water and tonic, including light tonic. The name of a brand or drink category is not enough to calculate a serving’s contribution.
Read the nutrition and ingredient panel on the exact pack, and check it again when you buy a different variant.
These labelled products illustrate differences between sparkling mixers; the brand references do not establish that a mixer is suitable as a complete marathon-fuelling drink.
Its tonic range includes light and other tonic variants. Fever-Tree lists sugar and quinine among the ingredients of Premium Indian Tonic Water.
Fentimans lists fructose, quinine, botanical extracts and stevia among the ingredients of its Premium Indian Tonic Water.
The range includes soda water as well as tonic products, so the exact variant matters.
These tonic waters are options when you want a sparkling serve around training. Check the exact variant before counting any of them towards a marathon fuelling plan.
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For a tonic-style sparkling serve rather than a complete run-fuelling drink. The Joybuy listing gives 3.8 g carbohydrate and 0.02 g salt per 100 ml for this variant; calculate any contribution using the amount you intend to drink.
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For a light Mediterranean tonic-style serve, this pack contains 8 × 150 ml. Check this variant’s nutrition panel before counting a can towards carbohydrate or salt intake; values from another light tonic do not describe it.
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For an Indian tonic-style sparkling drink, this pack contains 8 × 150 ml. Read this variant’s carbohydrate and salt figures before deciding whether it contributes anything useful to your planned intake.
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For a slimline tonic-style serve, this pack contains 12 × 150 ml. Check its own carbohydrate, salt and ingredient information; the figures for Schweppes Soda Water do not apply to this tonic.
Do not assume it can. World Athletics lists up to 90 g of carbohydrate per hour for events lasting more than 2.5 hours, so check what your complete food-and-drink plan provides. Coca-Cola Great Britain labels Schweppes Soda Water at 0 g carbohydrate per 100 ml; a sweetened mixer’s contribution depends on its exact label and the amount consumed.
No automatic conclusion follows from the presence of bubbles. A study published in the International Journal of Sport Nutrition found no significant average change in gastric function, perceived gastrointestinal comfort or exercise performance under its tested conditions. Try your exact drink and planned amount in training, because that study cannot predict individual comfort.
A sweetened tonic can contribute the amount shown on its label, but it is not a complete plan by itself. Fentimans lists 4.4 g carbohydrate per 100 ml for Premium Indian Tonic Water, while a Joybuy listing gives 3.8 g per 100 ml for Fever-Tree Refreshingly Light Premium Indian Tonic Water. Multiply the figure for your exact variant by the amount you plan to drink, then account for your other food and drinks.
Not necessarily. Runner observations published in the International Journal of Sport Nutrition and Exercise Metabolism found wide variation in sweat losses and required drinking rates. Use training runs to check whether your planned amounts are practical rather than copying another runner’s intake.
Start with carbohydrate, sugars and salt per 100 ml, then check the container size to work out the amount per serving. Read the ingredients for quinine or sweeteners where relevant, and use the exact variant’s panel: a soda water label cannot stand in for a tonic label.