There are five basic ingredients in sports drinks. The first is obviously water. Secondly is the carbohydrate; this is usually some combination of glucose, fructose, sucrose or maltodextrin. Glucose is moderately sweet, sucrose (a two-sugar molecule of glucose and fructose) is a little sweeter again, and fructose is very sweet. Maltodextrin is essentially a chain of glucose units joined together, and doesn’t taste sweet at all.
Most sports drinks these days use a combination of maltodextrin and fructose — the maltodextrin chosen to reduce the sweetness and the fructose to take advantage of the separate channel in the gut which absorbs fructose independently to glucose. This allows more carbohydrate to be absorbed from the gut simultaneously and allows carbohydrate intakes of greater than 60g an hour to be absorbed successfully.
The third ingredient is sodium or salt. Salt further reduces the sweetness of the carbohydrate, increases the rate of absorption from the gut and slightly increases the retention of fluid in the blood (so you pee out less if you drink more than needed).
Despite popular belief there’s minimal evidence that sodium during exercise prevents cramps, or that it can prevent hyponatraemia (low blood sodium) during ultraendurance exercise. To achieve this the sodium content would have to be so high that the fluid would be undrinkable (more than four times the sodium of ready-to-drink Gatorade). I’m not aware of a single performance-based study that has shown that the addition of sodium improves performance compared to no sodium in sports drinks, but the other benefits listed above probably justify its inclusion in your own homebrew.
Fourth is a source of acidity such as citric acid. This provides the characteristic “tang” of sports drinks and soft drinks. For a DIY sports drink you can use lemon or lime juice which also doubles as the final element: flavour.
So how much should you add of each ingredient? The carbohydrate will depend on how much you want. Sports drinks are typically around 6% carbohydrate — that is 6 grams for every 100mL of fluid. It is known from research that increasing the carbohydrate much beyond 6% starts to reduce the rate of stomach emptying, but recently it was shown that combining glucose and fructose allows the carb content to increase to at least 9% before any such effect.
Regardless, if it’s not causing gut problems or reductions in performance (it hasn’t at up to 12% carbs in the glucose/fructose combo) then does any of this matter? Given that sodium also doesn’t affect performance per se, I tend not to be too particular with this. Just go with whatever tastes good. The lemon or lime juice is about flavour so again add as much or as little as you like.
Here are a couple of recipes I make up when I’m riding. The first one is a milder flavour (and fructose free) but if I’m wanting to consume more than 60g an hour (in longer events) then I’ll go for the second recipe because it contains fructose, allowing more carbs to be consumed and successfully absorbed from the gut per hour.
In a 700mL water bottle combine:
- 6 level tablespoons of maltodextrin powder (or substitute some for equal amounts of glucose (dextrose) powder to make it sweeter)
- 1 pinch of salt (less than ¼ teaspoon)
- A squeeze of lemon or lime juice for taste (optional)
- 700mL water
- Carbohydrate: 69 grams (or 9.9 grams per 100mL), all glucose
- Sodium: Approx. 50mg per 100mL
In a 700mL water bottle combine:
- 2 level tablespoons of maltodextrin powder
- 4 level tablespoons of white sugar
- One pinch of salt (less than ¼ teaspoon)
- Squeeze of lemon or lime juice for taste (optional)
- 700mL water
- Carbohydrate: 69g (or 9.9 grams per 100mL), 2:1 glucose:fructose ratio
- Sodium: Approx. 50mg per 100mL
Glucose (often known as dextrose) and maltodextrin powder are available cheaply in the homebrew section of some supermarkets or specialty homebrew stores. They sell for around $5-8/kg.
I know a lot of people who prefer energy bars over gels, but it can be very expensive to buy lots of commercial bars all the time. I also know a lot of cyclists who use muesli bars or the softer baked fruit bars, but these are much smaller, and many can be quite dry and go claggy in your mouth when you’re working hard.
Many of you will already be familiar with The Feedzone cookbook from Allen Lim and Biju Thomas. The “rice cakes” in there are very well known. The search2retain boys made up a batch of these for the Melbourne-Warrnambool last year to provide something a little more substantial and a savoury alternative from all the sweet drinks, gels and bars over such a long race.
Here’s a video of Lim making the original variety of the rice cakes, but I believe the cookbook contains a greater variety of both sweet and savoury options.
If you’re wondering, the rice cakes contain around 30 grams of carbohydrate, a bit more than the average gel but about 15g less than most commercial energy bars.
The other recipe that I’m sure many long-time CT readers will be familiar with is the one for “Cocaine Bars”. Click here to read a previous post about these high-energy bars.
As you’ll see these bars pack a punch with calories, and contain almost 30g of fat each.
The nutritional breakdown for a 122g bar is:
- Energy: 2131kJ (509 Cal)
- Protein: 8.7g
- Fat: 27g (7.6g saturated)
- Carbs: 56g
- Fibre: 6.9g
- Calcium: 94mg
- Iron: 3.3mg
I’m aware that some people produce their own gels, using ingredients such as rice syrup, agave nectar and other sweet, sticky ingredients. These can be poured into re-useable gel flasks. I‘ve never tried making any of these but there are plenty of websites offering recipes. Here’s one of the better ones I’ve seen.
The other option is simply to use honey in a gel flask. There was some discussion a year or two ago about Capilano Honey Shotz. My observation at the time was that whilst honey is a pretty good carbohydrate source, the small serving size of the Honey Shotz means that you only get about 7g of carbohydrate per sachet. Simply pouring honey into a gel flask is a way to get a lot of carbohydrate into one container. Honey is 80-85% carbohydrate, so 1 metric tablespoon provides the same carbs as a typical gel.
There are other alternatives to gels and bars though. A colleague at the AIS got me onto savoury “gels” made from instant mash potato powder, maltodextrin and stock. These can be made in small snaplock bags, and whilst they are much bigger than a standard gel, they provide a more filling, savoury alternative. The search2retain boys also used these in the Warrny last year to the envy of the rest of the peleton.
Deb Savoury “Gel” – 26g carbohydrate (no fructose)
- Continental Deb Potato – 350g packet
- 4 cups of boiling water
- 1 stock cube (I use beef – it makes the gel taste like potato and gravy)
- 6 tablespoons of maltodextrin
- Add boiling water to Deb powder, stock cubes and maltodextrin and stir until it’s nice and smooth.
- Spilt into four equal quantities and add each to a small zip lock bag.
- Cut corner of the bag to create an opening, then fold over and tape shut with a printer label or masking tape.
- When it’s time to eat just rip off the label and consume like a gel
— Thomas.J.Donald (@ThomasJDonald) October 13, 2012
My final suggestion is the humble sandwich, tweaked for easy consumption on the bike. You can make these with Vegemite or peanut butter for a savoury version, or with jam for a sweeter one that’s a little higher in carbs.
Enduro sandwich – 22.5g carbohydrate (fructose free)
- Make your sandwich with white bread and cut off the crusts (too much chewing for not much nutrition).
- Squash it flat to remove the air. It should become about the thickness of a pancake.
- Cut it in half or into three.
- If you need to carry it with you wrap two halves in aluminium foil. It’s easy to tear open when riding that way.
Of course there are many other interesting things you can eat and drink on the bike. I’d love to hear about other options you use or have heard of.