9. You want to take your running fitness to the next level.
The 5K and 10K are wonderful entry-level distances for new runners. But, stepping up to the half marathon distance from the 5K or 10K distance will result in a veritable quantum leap in running fitness due to increases in mileage and the likely addition of one (or more) days of running.
10. You want to burn some extra calories.
A mile generally burns about 100 calories. If you're currently logging mileage consistent with running 5Ks and/or 10Ks, you're burning some decent calories. But, upping your mileage will not only take your running fitness to the next level, it will also boost your caloric burn.
More: 10 Ways to Cut 100 Calories From Your Diet
11. You want new kicks.
If you are stepping up from the 5K or 10K distance, logging a few extra miles each week will undoubtedly necessitate the purchasing of an additional pair or shoes or two. So, if you've been eyeing the hot new pair of Nikes at your local running specialty store, sign up for a half and pull the trigger as you'll likely need them soon.
12. Your wardrobe needs upgrading.
If you're going to be logging more miles, that may very well mean you're running more days per week than you have previously. These extra days of running will make it easy to rationalize upgrading your running wardrobe.
More: Top 5 Women’s Running Fashion Trends
13. You like to travel.
Given the range of half marathons out there, there are ample opportunities to parlay a half marathon into a running-infused vacation. Do you want to see what New Orleans has to offer? The New Orleans Rock 'N' Roll Half Marathon in early March is only a flight away. Want to explore a more tropical location? The ING Miami Half Marathon in late January might be right up your alley.
13.1. It's there.
Runners are explorers at the end of the day. As soon as we conquer one running goal, it's almost inevitable that we'll look toward the next one. Once you've logged a 5K, a 10K, and/or a 12K, it's almost inevitable the half marathon will beckon you to the starting line. Then, it may very well be on to the marathon.
Sign up for your next half marathon.