Energy bars work by delivering energy to your body in the form of carbohydrates, in an easy, portable format. They can be a great source of both fast and slow release energy (simple and complex carbohydrates) to fuel exercise and sport and help you to avoid burning out or ‘hitting the wall’.
So how exactly is a bar converted into energy in your body? When should you eat one? And what should you look out for? We’ve gathered together all the info on how energy bars work.
Do energy bars really work?
Whether energy bars work to boost your performance entirely depends on why you’re eating them, when you eat them and what ingredients are used.
For athletes looking for carbohydrates to power their physical activity then yes, absolutely! Energy bars are by definition high in readily available calories and carbohydrates, which makes them great workout fuel.
If you’re eating them purely as a healthy snack and hoping they’ll make you fitter and healthier, they may contain more energy than your body requires at that moment and may not be the best choice.
What happens to your body when you eat an energy bar?
The body breaks down most carbohydrates from the foods we eat and converts them to a type of sugar called glucose. Glucose is absorbed through your gut wall and then transported around your body in your bloodstream.
Your body then produces insulin, which tells your cells to absorb the sugars. Your body then has two options: burn the sugar molecules for energy now, or store them for later use. Most is stored in your muscles and liver as glycogen. These glycogen stores are your body’s ‘ready-to-go’ energy source. Any excess is converted to fat for longer-term energy storage.
If you eat an energy bar before or during exercise it does a couple of things. Firstly, it stimulates your body to regulate its glycogen stores for energy. Think of it like an ignition in a car. Secondly it provides a ready fuel source which can go straight from your bloodstream to your muscles without needing to be stored.
If you eat an energy bar after a workout, you’re giving your body the grams of carbohydrate it needs to replenish your depleted stores — promoting recovery and stops you getting hangry!
Glucose energy drinks, for instance, would be quick to work during exercise as the glucose doesn’t take much breaking down before you can use it as fuel. More complex carbs take longer but can provide a longer and more sustainable supply of energy.
The best energy bars provide a mix of fast- and slow-release energy, and can also provide your body with healthy fats, proteins and electrolytes which can all keep things running smoothly during exercise. Some even pack in health-boosting vitamins and minerals too.
How long does it take energy bars to work?
How long your body needs to absorb energy depends on the type of carbohydrate in the bar. Different carbohydrate sources metabolise differently, but as a generalisation, simple carbs like cane sugar, plant syrups (brown rice, maple, corn) and honey are absorbed more quickly to give a quicker energy boost. Complex carbs like oats, fruits and grains take longer to absorb and so can provide a slower release of energy.
You can start feeling the energy boosting benefits of simple carbs in as little as 15–30 minutes. More complex carbs can take longer (1-2 hours).
Some bars, especially those with real food ingredients, do a good job of combining fast- and slow-release carbohydrates to give both a quick energy boost and a long-lasting supply of fuel.
When should you eat an energy bar?
The advice on when to eat energy bars also depends on the kind of carbohydrates in the bar, and how long or strenuous your exercise is.
If you follow a healthy balanced diet, your body should have enough energy stored as glycogen to exercise for around 90 minutes. But because carbohydrates take a little while to metabolise, you’ll need to start fuelling before you run out.
So if you’re running for two hours, for example, you should start taking on energy before you need it, from around 30 minutes into your session. Then you’ll need to keep a steady stream of energy coming in every 20–30 minutes to prevent blood sugar levels from dipping too low.
If you’re up for an early morning cycle on an empty stomach, then an energy bar eaten 30-60 minutes before exercise will give you a decent start.
And if you’re not exercising? You might be tempted to reach for an energy bar as a snack but remember that they are high in carbs (and some of them contain very little else in the way of nutrition) so they’re best eaten as part of a healthy diet and an active lifestyle. Veloforte bars offer a balance of fast and slow release carbohydrates, heart healthy fats and plant proteins so they can be a good healthy snack, but perhaps not every day.