At HKRS we get asked how we decide how far kids should run based on their age, and there are a dozen different schools of thought about this specific subject. We age grade our races by recommendations from similar events, grade school athletics, and our own parental thoughts about the subject. While looking into the subject, I stumbled on a great article from Runner’s World from May 2016. The article suggested that the best way to decide on how long is too long for a kid to run is to allow them to dictate (within reason of course…) how many miles they want to log.
One of the main concerns is adding mileage too quickly. Kids, teens, and even adults should use the 10% rule as a general guideline for increasing running miles. Aim for 5 runs per week and only increase the total number of miles by 10% at the very most. For example, if in week 1 you run 10 miles, only increase your mileage to 11 miles (i.e. 1 mile, or 10% of 10 miles).
Next, it is very important to track weight and nutritional input for your kid. When beginning to run longer distances it is very important that your child is maintaining proper nutrition and not losing a significant amount of weight at one time. Extreme weight loss, even for individuals that need to lose weight, should be part of a gradual process. Fast weight loss can lead to another host of issues including fatigue, bone density loss, and trouble sleeping.
Finally, allow your child to make it their own decision! Let them have autonomy while maintaining safety. Of course you don’t want your child to quit miles away from home and jeopardize their safety, but short runs or loops around the neighborhood can be very beneficial to their healthy and foster a sense of independence.