After a while of running you’ll realize there are some who manage to, amid all of lifes other commitments, run twice a day. You’ve heard these people will, after having already ran in the morning and gone about their day, tie up their shoes again and run more. They use the word “doubling.”
So, should you try doubling?
Running twice a day is common among the elites ranks of middle- and long-distance running. It allows athletes a way to, once they’ve already reached a point where there isn’t much more they can do without risking injury, get a bit more mileage. These are athletes who have been training at a high level for quite a while and their situation is likely different than your own.
That doesn’t mean you can’t benefit from running twice in a day, but it may not be for the same reasons. Before jumping into it, think about your current training? How comfortable are you with the mileage you already run? Do you have days where your runs leave you feeling exhausted? If you’re thinking about doubling, you’ll need to be able to honestly tell yourself that your current workout regimen isn’t taxing you too much.
Also, why do you think you need to be doubling? In general, one single run in often better for you than two shorter ones. You’ll gain more benefits from running 15K once than if you run 7.5K twice. This is the same reason why it’s unadvisable to split up a long run. You make the largest physiological gains between the 60- and 90-minute range during your runs.
If starting to double is still sounding like something you may benefit from, like anything else, ease into it. Start by picking one faster workout day where you can run again five to ten hours later. Do about half of the distance you normally would and keep it easy. From there, keep it to one day each week for a few weeks. Once you feel comfortable with that, try two days per week.
Doubling can be great for aerobic fitness, but overtraining is a real problem if you’re not careful. Only think about it if you’re feeling confident you’re fit and healthy enough to benefit safely. If you start feeling exhausted all the time, scale back the mileage and stop running twice any days.