There is no doubt that consuming carbohydrates during long races has a positive effect. And the more carbohydrates you are able to consume, the better your performance is likely to be.
Consuming carbohydrates during training is, however, another matter. Here you can both select and deselect the carbohydrates strategically, all depending on what you want to achieve with your training.
In this article I will come up with some general guidelines and good advice about when you should use carbohydrates in your training and how much you should use.
The reason why consuming carbohydrates during exercise can be a bit of a dilemma is becuse the are a number of pros and cons associated with it.
It will always be a dilemma between ensuring the best possible energy level during your training, allowing you to maintain a higher pace during your training while consuming carbohydrates on the other hand may dampen some of the beneficial effects training may have on one's fat burning and endurance.
Read more about energy for running and the importance of carbohydrates here!
In the table below, I have outlined some of the obvious advantages and disadvantages of consuming carbohydrates in connection with exercise.
Advantages:
- Increases you training capacity as the energy consumption provides options for increasing the pace towards the end of your workout
- Getting adjusted to consuming carbohydrates can reduce stomach trouble during competitions
- May improve your recovery after training
Disadvantages:
- May reduce training response related to fat burning and endurance
- May be a hassle to carry during workouts
- May cause stomach trouble during training
When should carbohydrates be used?
When to choose to use carbohydrates in your training, depends a lot on what you want to accomplish. As the table above suggests, consuming carbohydrates provide you with the capacity to work harder. On the other hand, it may dampen the endurance response you would otherwise receive from an extended workout.
Consequently, to put it more simple, it will be a question of quality or quantity. I use it a lot myself during my workouts. Not in all my workouts but in carefully selected workouts. Below I will try to outline different situations where I would use it and not use it.
Situations where I would use carbohydrates:
-
If the competition, I am preparing myself for, is so long (over 1 hour) that I need to consume carbohydrates during racing, I would during the last four to five weeks of my training consume the same amount of carbohydrates that I plan to do during the competition. I will do this on all specific workouts - longer intervals and long runs - but not during the intermediate short and easy-going runs.
The purpose is to incorporate a good habit in relation to consuming carbohydrates during your race as well as to adjust your digestive system to absorb energy during hard physical work. Research have shown that your body can adapt itself to consuming carbohydrates and that people who practise it will reduce potential stomach trouble during competitions.
Amount: Depends on the competition, you´re preparing yourself for. Generally the guidelines below will fit most people. However, higher amounts will require more adaptation.
1 – 2 hours = 30 – 60 g/hour (pure glucose or glucose-fructose mixture)
2 – 5 hours = 50 – 70 g/hour (glucose-fructose-mixture)
+5 hours = 70 – 100 g/hour (glucose-fructose-mixture)
A normal package of gel will typically contain 20-25g carbohydrates.
-
If I am going for a really long workout - typically more than 2½ hours - I would consume carbohydrates throughout the workout to maintain a fairly stable blood sugar and to be able to keep a proper pace towards the end of the workout.
If you "hit the wall" during your training, it can extend your recovery afterwards fairly extensively. On the other hand, research have shown that you can reduce your recovery by consuming carbohydrates during your workout. You reduce the risk of injuries and you will recover faster for your next workout.
Amount: Typically between 30-60 g/hour depending on the distance. Longer runs at low intensity requires more carbohydrate consumption.
-
If your workout is focused around speed and high intensity, you can improve your performance towards the end of the workout if you consume carbohydrates. I. e. if you are training towards a 5 or 10 km race, where you otherwise don´t plan any carbohydrate consumption during the race, it can be an advantage to consume a small amount in between the intervals of the longer intervals sessions. This can improve your performance and your speed practise.
Amount: Typically around 20 – 30g for the complete workout session. Possibly as small sips you gargle in between the intervals.
-
If you haven´t had enough to eat before your workout and already feel short on energy before the start, it might be a good idea to consume a small amount of carbohydrates before or during the workout to complete it in the best possible way.
Amount: May vary according to the workout and how much energy you feel you are lacking.
Situations where I would not use carbohydrates:
-
If I go for medium-long runs - typically 1½ to 2½ hours – where I am focused on improving my general fat burning capacity and endurance and when there is still a long time until the next race. In this case I would stick to pure water during the workout as the consumption of carbohydrates possibly can dampen your fat burning capacity and endurance. If you are in great shape, you also won´t feel the need for any carbohydrates during these workouts.
-
If your complete workout takes less than an hour, you won´t need any carbohydrates. Even if performance effects has been proven from rinsing your mouth in sugar water during very intensive 30 min. workouts, the effects are relatively small. So, you hardly gain any advantages by consuming carbohydrates during your workout.
-
On all intermediate light workouts lasting up to 90 minutes, its simply not necessary.
Summary
To sum up, I would use carbohydrates in specific workouts in preparation for an important race, during super-hard intervals where you are focused on high speed and during really long workouts. On the other hand, I wouldn´t use it for semi-long, easy-going workouts, or lighter, intermediate training sessions and if the duration of the workout is less than an hour. The amount of carbohydrates slightly varies according to the workout and which race you are preparing yourself for, but it will typically be around 30 – 70 g/hour. If you are preparing yourself for a very long ultra running race, you could perhaps experiment with as much as 70 – 100 g/hour. This should, however, be tested during your training before doing it during a race.
