Dr David’s Secret Sauce

Following from the previous blog post on hydration, energy and salt strategies…

A rough guide to using maltodextrin powderwitches-and-brew

Maltodextrin is ideal for adding to your water bottle as a relatively pure and cost-effective source of energy during a ride. It can be flavoured with your favourite squash with some added salt or used with electrolyte tablets (which could be flavoured).

Maltodextrin is a high Glycemic Index (GI) polysaccharide that is soluble in water and not sweet. It provides a fast acting energy source and is rapidly absorbed and less likely to cause nausea than glucose or sucrose.  It is relatively cheap and used in the food industry. The maximum GI is 100.

Most energy gels contain a mix of sugars including glucose (GI=100), fructose (GI=25) and maltodextrin (GI=100) plus flavours and other additives.

Cost compared to commercial gels

In terms of the cost per gram of pure energy, Maltodextrin costs only 1/10th to 1/20th the price of gels!  (Maltodextrin = 0.27p/g; Wiggle gel =2.1p/g; SIS Go = 4p/g)

Cost compared to commercial powders

SiS Go Energy powder £26: 50g per serving, giving 47g carbs (1.6Kg, gives 32 servings of 50g = 81.25p/serving of 47g carbs = 1.73p/g), meaning Maltodextrin costs a mere 15% of SIS Go Energy powder.



sucralose-3d-ballsMaltodextrin Powder

Each 39g/scoop  (3.8 kcal /g) = 150kcal

2 scoops per 750ml bottle = approx 10% (300kcal)


Typical Usage


Try to drink 500ml of fluid (an energy drink or fruit juice) 45-60mins before exercise.

If you’re having breakfast before the ride, make sure it’s at least 1hour before – porridge is always a good choice. Don’t drink large quantities otherwise you’ll be stopping every 5 minutes for a nature break.


During exercise

popeye-spinachIdeal is around 60g low GI carbs (288 Kcal) per hour and 600mg Sodium.

That might look like this:

Summer drinks 5% (1 scoop) plus Sodium 700mg (2g salt)

Winter drinks 15% (3 scoops) plus Sodium 500mg (1.3g salt)

Drink 625-1250ml per hour (one to two bidons per hour…yes, that much!) – depends on weather, the person, how hard you’re riding.


Post exercise

When you get off the bike, you will be in energy deficit so I recommend you consume 75g High GI carbs (330kcal) immediately after the ride and another after 1hour to make up deficit of calories. Also protein is essential to rebuild damaged muscle fibres.



1litre of sweat contains up to 1g of sodium (=2.6g of table salt). Sweat loss can be 500ml – 1L per hour

Table salt contains 387mg/g. So 1 teaspoonful = 6g = 2300mg

Energy gels generally contain 22-30g carbs which is 80-115kcal plus Sodium 10-40mg. So 2-3 gels per hour will supply the maximum calories one can absorb but not enough Sodium.

High GI carb intake after exercise stimulates Insulin release that encourages muscle growth and thus strength! 

Useful links for further information: