Heres your instruction manual.
Why eat on long runs?
Our muscles store carbs in a form called glycogen.
If youve ever carb loaded with a pasta dinner, you were filling up your glycogen stores.
We also have carbs floating through our bloodstreamthis is what blood glucose means.
During exercise, our bodies use both of these sources.
For short workouts, we have plenty of glycogen to carry us through.
Do youneedto fuel on long runs?
Our bodies can work for a long time whether we eat or not.
But as our internal carb supplies diminish, well feel sluggish and well slow down.
We may also have a harder time recovering from that run afterward.
If you usually do long runs on an empty stomach, try fueling for your next one.
Youll notice a big difference in how you feel.
How long of a run requires fueling?
But theres room for experimentation.
You dont have to forgo the fueling if your run is 89 minutes.
How much do I need to eat on a long run?
The general recommendation is to aim for 30 to 60 grams of carbohydrate per hour.
But research shows that people tend to feel and perform better when they have more carbs.
Three gels per hour would be 66 grams of carbs, and that would be fine.
A gel every 45 minutes may be a good place to start.
Youll also want to check that to start with some carbs already in your belly.
What makes a food good for endurance fueling?
The simple answer is that we want carbs that digest quickly.
Glucose, a sugar, is the carb that we use most readily.
Sugar, in the sense of table sugar, contains glucose and fructose.
Stomachs vary, so what works for one runner may make another queasy.
Can you fuel with drinks?
There are sports drinks that say they contain enough carbs to fuel your training.
Youcanfuel with drinks, but theres a problem with many of them.
In other words, youll get what runners politely call GI [gastrointestinal] distress.
This can take the form of burbling guts, farting, andfar more often than wed like to admitdiarrhea.
The ratio of sugar to water seems to be what causes this.
Full-strength Gatorade is notorious for setting off bouts of diarrhea if you drink enough of it.
Water it down to half-strength, though, and youll likely be fine.
Its sugar concentration is a lot easier on the gut.
(Caffeine can improve athletic performance, but can also keep you up at night.
You may want caffeinated gels for morning workouts but not evening ones, perhaps.)
When youre 12 miles into your long run, youll hate them all.
But remember what makes good run fuelit doesnt have to be a commercially processed, sport-scientist-optimized packaged product.
It can just be any old food with carbs.
(That said, we will attempt to forgetHeinzs push to make ketchup packets into running fuel.)
Pouches of applesauce or baby food - check the label, since carb content varies.
Dont forget that you might just look around your kitchen and grab whatever seems appetizing.
Cookies may not be optimal running fuel, but they have fueled many a run.
