Long runs can be challenging for a number of reasons - time, distance, boredom and fitness are all important factors to consider. Hydration and nutrition durant your run is one that should not be forgotten.
General rule of thumb, if you’re heading out for a run that will last longer than 90 minutes, water and food (many like to use gels) are super helpful. For starters, hydration pre-run is incredibly important - according to a study by Armstrong and Costill in 1985, only 2% decrease in body weight that is attributed to water loss can cause a runner to slow down by almost 7%! So by being well hydrated pre-run, you are ahead of the game on this one. In a marathon, it is estimated that a runner can lose up to 10% of their body weight..!
Hydration during exercise, though, will help keep some of the negative side effects of dehydration (i.e. increase in body temp, elevated heart rate, decrease in performance) at bay.
In terms of nutrition, whatever you ingest will help keep your glycogen levels from crashing too low - and in turn, will keep you going for longer. The amount, however, is very much up to the runner. I eat every 30 minutes after I’ve passed the 40 minute mark in my long runs. Some go as far as suggesting that athletes should be ingesting carbohydrates every 10 minutes! My pick: either a lara bar (cashew cookie is my fave) or sharkies.
What about electrolytes? Sweat is composed of water and electrolytes, right!? Yes, electrolytes are lost during sweat. But they are also (mostly) lost during urination - who’s rate decreases rapidly during exercise in order to control homeostatic levels of electrolytes. This is a topic that I’ll have to go into detail to explain, but the short of the long is that sodium lost through sweat do come back to normal levels about 48-72 hours post long run. This is with or sans replenishment via “electrolyte” beverages (ie. Gatorade).
Finally, post run. Of course, post run is very important for recovery. Typically, I will have a meal comprised of eggs and sweet potato or oatmeal following a long run. That way, I have a good mix of protein and carbohydrates to help with muscle repair and glycogen replenishment. One study in particular has shown that post exercise, recovery-type drinks containing both carbohydrates and protein are much more efficient at replenishing muscle glycogen than beverages such as Gatorade and Powerade. So if you are stuck, go for something with a combination of nutrients.
Ok! Rest time for this girl. Tomorrow morning, I’m heading out with the “dream team” at Broadway Run Club for a 21k run. When training for a sub 3:30 marathon (my “official” goal for Boston), long runs should be anywhere between 5:30 and 6:30 min/km. I don’t plan to keep up for most of it as they run a 4:30 min/km for their long runs, but hey - one can always dream!