Should you fuel up before running?
The answer is no surprise: YES!
Ideal timing and meal recommendations: if you have 2-3 hours prior to your run
When it comes to regular training and practice, 1st, the pre-training fueling is very important – just like you have to keep your tank filled before driving anywhere. The ideal timing for pre-running meal is 2-3 hours prior and the meal should have sufficient amount of complex carbohydrates and some proteins because the complex carbohydrates constitute good and accessible fuel for you to use during running.
Good examples include oatmeal, bagels or breads with nut butter (peanut butter, almond butter, cashew butter, etc.), cereal, hard boiled eggs, yogurt, some sweet fruits such as bananas and apples.
Early morning training & snack recommendations: if you only have 1 hour before your run
However, if your training run is early in the morning, it is hard to have a 2-3 hour lag betwee
n your wake-up time and running time. But if you can manage to have at least 1 hour between your eating time and running time, you should still be able to have sufficient intake of easily digestible, simpler carbohydrates readily available for your run.
Some good examples are yogurt, white rice, bagels, banana’s, apples, dates, raisins, etc.
Recommendations if you barely have 30-40 minutes to eat before your run
If your morning get-up time is no more than 30 – 40 minutes or so before your running time, then it is not advisable to eat too many solids.
Solids eaten at this time will go through prime digestion window just as you peak at your physical activity, and the in-digestion slush will get churned up and down in your digestive track, just like clothing get thrown and spun in a washer machine, powered by your bouncing moves. You can imagine how this running “washer machine” activity would “enhance” your running or digestion…
So if you only have 30-40 minutes or less before start running, some good liquid options include commercially available carbohydrate fuels, which usually come as easily dissolvable powders; such as carbo-pro from carbopro.com, commonly seen gels (such as GU energy gels available at many running stores or online), and many other sports drinks that has carbohydrates in addition to minerals. A small banana or apple can also be tolerated.
The key is carbohydrate loading
It is very important to eat your pre-running meals, snacks or liquid fuel that have sufficient carbohydrate content. Ideally, you want to preload yourself with fuel for the training needs of the run you are about to do. If you were able to do some carbo loading the day before your running, you can rely a little less on the pre-running meal, but it is still advised not to skip that meal.
Results of running on an empty stomach
There are many runners who can do their morning run on empty stomach, but the real problem is that depletion of your glycogen of the skeletal muscles and the liver will make you excessively hungry after running, and you will more likely to over replenish your carbohydrate fuel after the run. The excess carbohydrates you eat will be converted to fat, which does not help you with either your performance or weight loss/maintenance goals.