As you ramp up your training volume here are a few things to keep in mind that the scientific community has learned about endurance nutrition. The team at GU Energy is proud to be the official on-course energy product of the San Francisco Marathon and we have spent nearly 20 years working with professional athletes and leading scientists to formulate and optimize performance energy products for endurance athletes.
- On average, athletes need to take in about 200-350 calories an hour during a multi-hour endurance event like the SF Marathon. Anything more than that and you risk decreased performance due to gastric distress.
- Athletes need a significant amount of those calories to be carbohydrates (anywhere between 40-60 grams) due to the body’s need to use glucose as fuel during endurance exercise. Endurance events can burn through the body’s stored glycogen pretty quickly. That’s what’s called bonking and that’s why you need to eat DURING the event. Keep the glycogen pilot light burning and stay hydrated and you cross the finish line. It’s that simple.
- Humans need at least 15-30 oz of water per hour during endurance events, depending on heat, humidity and pace (among other things). Performance decreases after losing just 2% of body weight from dehydration.
- Electrolytes help the body retain the fluid you do take in and put it to work in muscle contractions, which means you can go faster and stay out longer.
- It takes between 24-48 hours to completely recover from a workout and replenish your glycogen stores, which is why taking a well-formulated recovery drink inside the magic 30 minute “Glycogen window” after training is so important – fail to replenish your fuel stores and you fail to be ready to train again the next day.
You can see how all of these principles require the athlete to practice and customize their nutrition plan before race day. We design GU products with these needs in mind and that is why we recently launched the Performance Energy Sampler and created the first gel way back in 1991.
The original idea behind GU was to find the quickest way to deliver an appropriate amount of calories to an athlete during competition without upsetting his or her stomach.
You’ll notice there is maltodextrin in GU gels and maltodextrin is a complex carbohydrate (remember the 40-60g of carbs per hour from above?). Studies have shown that some complex carbs are digested faster than simple sugars like table sugar and honey. There is also fructose in GU gels which your stomach processes much faster than maltodextrin but doesn’t produce a sugar high which you might get from those simple sugars. This matters because the quicker your body can process the carbohydrates the less blood needs to be diverted from your muscles to your stomach to process the sugars. You go faster and stay out longer as a result.
Taking 1 packet of GU Gel and mixing 1 packet of GU Brew Electrolyte in a large water bottle gives you the right calories (240), fluid (20 oz.), electrolytes (sodium and potassium) and carbohydrates (54g) that you need to sustain a winning pace.
And lest we forget recovery, that oh-so-important but often neglected part of training. You’re probably running multiple times a week now with many back-to-back training days. You’ll need to recover after each one to train hard the next day so make sure you are taking a recovery drink within 30 minutes after each workout over 90 minutes or so.
Enjoy the time spent training and best of luck on race day!