Energy gels versus energy bars

We explain how each is digested, how quickly you feel the affects, and the benefits of each

Whats the difference between an energy gel and an energy bar


Energy gels are the halfway house between solid food and liquid nutrition (that is, sports drinks). They’re immensely popular because they’re easy to carry and to consume and digest on the move. They mainly contain simple carbohydrates, such as glucose and fructose, but some also have added electrolytes and caffeine.


1 When you squeeze an energy gel into your mouth, the body starts to break it down almost immediately using an enzyme called salivary amylase. The gel then makes its way down into your digestive system as you swallow.

2 Within the digestive tract, the carbohydrate in the gel is broken down into smaller molecules that can cross from the small intestine into the bloodstream.

3 Once in the bloodstream (as glucose), the carbohydrate triggers the release of a hormone – insulin – which activates your cells to either grab the glucose and use it immediately for energy production or store it for use later on.

4 This all happens relatively quickly for simple carbohydrates and you can expect to ‘feel’ an energy gel working within 15mins of consuming it.

5 It’s often necessary to wash energy gels down immediately with water in order to help them digest quickly and to stop your mouth becoming too dry from the texture of the gel.


Energy bars are designed to provide a concentrated amount of energy in the form of carbohydrates to fuel muscles before or during exercise. They generally release energy a little more slowly than carbohydrate gels or drinks as they take longer to break down, so are more suitable for pre-exercise carbo-loading. Some may contain small amounts of other nutrients, such as protein or substances like caffeine.

1 When you start eating an energy bar, your mouth immediately begins to break down the bar’s simple sugars using salivary amylase (in the same way it does with an energy gel). As you chew it up and swallow the bulk of the bar, it moves into your digestive tract to be broken down further.

2 Within your gut, the carbohydrates are broken down into small molecules that can cross the intestinal wall into the bloodstream. This happens more slowly than with a gel or drink; some of the carbohydrates are more complex and require more processing.

 3 Once in the bloodstream (as glucose), the carbohydrate triggers the release of the hormone insulin, which activates your cells to take up the glucose and either store it as glycogen for use later on or, if you’re training, at the time when it’s consumed.

4 Energy bars are a very dense source of carbohydrates and tend to have a long shelf life. They are an extremely convenient way of making sure your glycogen stores are topped up before training and competition if you don’t have access to more natural foods. You can find recipes for homemade energy bars here