How far is "too far" for children to run?

I started to answer this question at the beginning of 2023, following UK Athletics reduction in the maximum distance for Under 9’s cross-country races. Also, I had a suspicion that children doing adult Parkruns maybe was not such a good thing, when there were Junior Parkruns which were much shorter. I have had many parents contacting me about wanting their child to join the Juniors extolling their child's love of running (adult) Parkruns as good reason!

UK Athletics reduced the maximum XC course distance from 1600m to 1200m for Under 9’s. NB Junior Parkrun is 2000m, Adult's Parkrun is 5000m..

So how did I try to answer this question?

• I contacted England Athletics and they stated it was a decision made by them based on the latest research, captured in their “Youth Endurance’ report, 2022, and also more recently from the Children’s Health and Exercise Research Centre (part of the University of Exeter).

• I contacted the Professor Craig Williams, Head of CHERC, and he was very helpful sending me some technical literature that was not too difficult to understand.

So what did this and also doing some internet research tell me?

There is evidence that children can and do run long distance races, seemingly without ill affect (at the time), but not surprisingly, there’s no research using controlled trials to determine what training regimes would result in harm in children, because it would be totally unethical. So the recommendations on what are suitable distances for children to run are based on expert judgement by people who understand children's physiology and development, and the sports concerned and the consequences of doing them, such as Prof Williams.

I won't go into a long explanation of the physiology of children and how long runs potentially impact on them, but will state the scientific consensus that the risks of children doing too much endurance running are twofold:

• Mental - burnout children may lose their interest in sport, especiailly running, from overload

• Physical overuse injuries -,

  • Osgood-Schlatter’s and Sever’s diseases, related to problems with tendon attachments

  • medial tibial stress syndrome (aka shinsplints)

A good article on this subject by Anna Gardiner was published in Runner’s World in May 2022, "What amount of running is safe for children and teenagers".

There are other health risks, such as REDs, but that would be in extremis (probably more of an issue for Teenagers).

So, if your child joins you for a (5k) Parkrun once in a while, it will probably not do them any harm, but I would think twice before making this a regular activity for them.

But actually, although I wanted to understand what led to the reduction in recommended maximum distance for children to run XC, it’s not really the right question for me to ask. The best question is “what form of training is best for children”? So, I will answer that next time!

Dorian