RaceGrader - Authentic Race Reviews - Swim, Bike, Run

Should Kids Run Long Distances?

Posted by: on June, 14 2013

Should Kids Run Long?

Can too many miles ruin young runners?

Mark Hadley has heard it all. The father of junior high phenom Alana, who ran 40–50 miles per week as a 12-year-old and is now up to 70 –75 per week as a 14-year-old, has been told that she’ll damage her joints, destroy her health, wear out, burn out. One local coach even said, “That’s it. You’ve ruined her. She won’t grow any more running all those miles.”

When we published a brief profile of Hadley in our September 2010 issue, we saw similar reactions. Well-meaning readers asked whether she wasn’t putting her health, not to mention her athletic ability, at risk. Wrote one, “I would be surprised if over or anywhere near 50 miles per week for a 13-year-old girl is not having a debilitating effect on her growth and physiology.”

While not questioning the concern and good intent of these reactions, we wondered whether they had any scientific validity. There is, of course, the example of African youth, who, while they may not run as much as some legends suggest, put in far more miles, simply as transportation, than most American youth even in aggressive training programs. Elite coach Joe Vigil often estimates that, by the time they reach high school, Kenyan youth have run as much as 10,000 miles more than their American counterparts. A Scandinavian researcher, Bengt Saltin, found in a 1995 study that active Kenyan school children covered on average 8–12K a day. That’s a weekly total of 35–50 miles.

Are American kids different than Kenyan kids, we wondered? How much can kids safely run? Or might this concern for kids’ health be more like the notion, 100 years ago, that marathons would make you “go stale” and break down your health, or 30 years ago that women would damage their reproductive organs by running long, or even the persistent myth that running will ruin your knees and give you arthritis?


The short answer to that is yes. “It’s basically an urban legend,” says Cathy Fieseler, M.D., practicing sports physician on the board of directors of the American Medical Athletic Association. While you won’t find controlled studies on this, as you can’t put a group at health risk for science, Fieseler maintains, “You’ll find no data that kids will tear up ligaments, destroy cartilage or damage growth plates with high mileage. You don’t need to put a top limit on it.”

William Roberts, M.D., medical advisor for the Twin Cities Marathon, has conducted several studies on young marathoners, a self-selected group of young high-mileage runners, and has come to the same conclusion. “Kids and mileage basically makes us nervous,” Roberts says, “but from all I’ve found, there is no harm being done; they are not getting hurt. If it is their choice, keep doing it.”

A study on overuse injuries and burnout in child athletes published in the June 2007 issue of Pediatrics points out, “Endurance athletic events (triathlons, marathons, and half marathons) are becoming more popular in the United States, and legitimate concerns have been raised for the safety of youth participating in these events.” The report concludes, “There is, at present, no scientific evidence that supports or refutes the safety of children who participate in marathons. There are no recorded data on injuries sustained by children who run marathons. … Ultimately, there is no reason to disallow participation of a young athlete in a properly run marathon as long as the athlete enjoys the activity and is asymptomatic.”

Tim Noakes, M.D., professor of exercise and sports science at the University of Cape Town, concurs, stating in his Lore of Running, “It is important to stress, however, that there is no evidence for any negative physiological effects of intensive training by itself in the prepubertal period.” He goes on to say, “There is no evidence that either children or adults can train themselves to the point where they suffer lasting physical impairment,” and, “Gifted young runners [6-to 10-year-olds], who choose to run these distances [excess of 8–10K] are at no greater risk of an unfavorable outcome or injury than are adults completing the same distances under the same environmental conditions.”

Elite coach Brad Hudson, who famously ran mega-miles as a youth (100 miles per week as a freshman in high school, up to 140/week before he graduated), agrees strongly that high miles won’t hurt a young runner. “I was extreme,” Hudson admits, “but I was self-motivated. I ran a lot because I was a crazy kid. The biggest factor is that they have to be enjoying themselves. But if they are enjoying themselves being pushed, that’s OK.” Hudson didn’t suffer from his early miles, going on to garner All-American status in the 10,000m and eighth in the NCAA cross country championships while at Oregon, and running a 2:13 marathon PR post-collegiately.

In the case of Hadley, she’s grown 6 inches in the three years since the coach’s dire warning that she’d stunted her growth. In her eight years of running consistently, she’s never had a running injury. And, on the eve of the early February USATF Cross Country Championships when I interviewed her, she was dancing in circles in anticipation of getting to run against some of her heroes the next day: “I get to race Aisling! [Cuffe]” she blurted, throwing up her fists in glee, when asked if she knew who else would be in her race. No sign of burnout yet.


If running long isn’t detrimental to youth, where does the fear enter? For some, it seems a case of projection: Adults get injured when they go too far (often too soon, with poor mechanics and/or carrying excess weight). They find running difficult, dutiful and painful. They wouldn’t want to inflict this on kids.

Charlie Brenneman, coach at Granite Oaks Middle School in Rocklin, Calif., sums up this cultural aversion nicely:

“That this is unusual mileage for a 13-year-old is because of two problems: One is that running is widely considered punishment. It is punishment/torture to non-athletes for sure, and in ball-dominated sports they have to run when they do something bad. The second problem is the obvious one: We’ve just gotten soft (convenienced) in this country and, as a result, ridiculously and dangerously unfit. This is why one hour of running for a child with limitless amounts of energy and enthusiasm elicits such a negative response.”

Mark Hadley blames the shock on the listener’s frame of reference. “People just don’t have the frame of reference for kids running a lot of miles. They don’t know that someone like Magda [Lewy Boulet] runs 140 miles per week. You go and get your Hal Higdon marathon program, and advanced is 40–50 miles per week. When they hear a number like 70! …”

It’s not fair to project our societal bias on kids, who, if given the right context, will run for hours at play with the natural joy and freedom of wild horses on the prairie. The greater problem is that they aren’t doing this, of course: For the most part, they’re either becoming sedentary, watching TV and playing video games, or they’re in uniform, listening to a coach or working on skills in a structured, organized sport.

Today’s culture of extensive and intense youth participation in sports presents a legitimate concern that those who balk at kids’ mileage are reflecting. The world of organized kids’ sports starts early, as young as 3-year-olds, and comes with significant parental and community pressure. In Game On, Tom Farrey describes kids’ sports as “a world desperately organized around the principle of identifying and promoting–and often exploiting–the next generation of athlete-entertainers.”

Linking athletics to entertainment, Farrey identifies what seems to me one of the key drivers of sport in our celebrity-crazed culture: the possibility to become someone famous, someone real, someone on TV. To get there, parents will too often push their kids to take sport far more seriously than they’re prepared for at their age and rob it of any resemblance to play. In this context it’s no wonder that many grow leery when hearing about a young teen running more miles than they would.


The big question every coach, doctor and letter-writer brings up is: “Who’s driving the program?” And all the experts and coaches agree: The child has to be driving it, the child has to choose it and continue to want to do it every day. It has to be fun. The child needs to have the desire, not the parent or grandparent or neighbor.

This doesn’t, however, mean that parents and coaches shouldn’t provide a context that encourages running nor that we can’t promote excellence. “Let them have fun” doesn’t mean, “Let them do whatever they want.” We want our children to be happy, but few of us want them to be happy living in a van down by the river. Most parents want their children to become disciplined, industrious citizens, adults who know how to set goals and taste the joy of accomplishing them–learning these life lessons is a big reason to participate in sports. And learning to do something well can be more fun than passive pleasure, even for a kid.

The fun ends, however, as soon as children feel forced to participate or compete, or that they have to live up to external expectations, particularly expectations that exceed what they can perform. Parents have to continually examine their motives and their interactions, ensuring that they’re not projecting their success desires on their child, which can be communicated as subtly as excessive focused praise such that the child feels he or she must succeed to be loved. Fieseler emphasizes that young runners have to have a “back-off clause” that they can employ at any time. A child shouldn’t have to dread a workout or a race, or respond, “Do I have to?” when it’s time for practice. (Hadley, when asked, could recall only one day in her eight years of running when she didn’t want to go out–and she was sick that day.)



Given a child who sincerely enjoys running and wants to do more, and accepting that kids can safely run far more than most ever do, the question becomes, should they?

In terms of athlete development, numerous sources indicate there’s little benefit in intensive and systematic training before puberty. Until puberty, children lack many of the hormones that allow for training adaptations in the muscoloskeletal system, and they’re poorly suited for longer bouts of intense exercise like interval training.

Younger children are well suited, however, to long, easy running, and can significantly improve their VO2 max and running economy by putting in miles. Several studies seem to indicate, however, that equal physiological changes occur when an older runner begins similar aerobic training.

These findings cause coaches like Jeremy Freeman from the UK to argue, “I certainly believe that such mileage at a young age is pointless and that if an athlete took up the sport at, for example, 16 years, they could (with correctly progressed training loads) catch the athletes who have already done three to four years of mileage.”

The African example would seem to counteract these beliefs. A 1995 study by Saltin showed that running efficiency was higher in Kenyan runners, even when trained Scandinavian runners nearly matched their VO2 max. While some, like Noakes, take this primarily as indication of superior running genetics and body type, even Saltin credited childhood experience, concluding, “It is the physical activity during childhood, combined with intense training as teenagers, that brings about the high VO2 max observed in some Kenyan runners. Their high aerobic capacity, as well as their good running economy, makes them such superior runners.”

Regardless of the athletic benefits, what are the risks? As in adult training, young runners can get injured if they progress too quickly or take inadequate rest between workouts and phases. (Note, however, that, also like adults, intensity is more likely to cause injury than easy miles.) More important than physical age is training age: A 16-year-old jumping from zero to 50 miles per week is more likely to get injured than a runner who started at 13 and built to that mileage at that age. (See sidebar on Hadley’s progression.)

Kids are also more likely to get injured when growing. Bill Hackney, community coach for the successful Marietta, Ga., Kell Middle School, says, “A youth athlete uses a tremendous amount of energy just for growing and this needs to be considered in developing the training program for that athlete. Many times what is interpreted as ‘burnout’ is really a young athlete hitting a ‘growth spurt’ or in the case of young ladies the onset of menstruation.” Mark Hadley says of Alana that he knows when she’s growing without using a yardstick, because her times will stagnate or fall: They take it easy during these times, and see them rebound and improve as soon as she levels out.

Many worry about burnout in youth who start early. While physical burnout is a myth (except for short-term overtraining, which quickly abates when the athlete takes a break), emotional burnout is often observed in early bloomers: At a certain age they’ve had enough. Often this is tied to situations where they’ve had excessive pressure, either overt or perceived, but sometimes they just tire of running competitively. Noakes again: “I would suggest the majority of successful child athletes retire from competitive sport for the same reasons as do adults. Either they reach the goals they set themselves, or they prefer to devote their time to developing other interests or facets of their personalities.” It’s important to note that the runner needs to have the freedom to do so, without feeling a failure for “burning out” and letting down all of his or her fans.

If a young runner is having fun and having success, however, should they be prevented from pursuing this to save themselves for possible greater success later? When a 17-year-old Kenyan runs a world-leading time, or when Africans take the first 28 places in the world junior cross country championships, do we question whether they should have run less as a child in order to peak six to eight years later?

Some argue that a runner doing too many miles early in life is left with little room for continued improvement: At some point VO2 max is maxed, whether they start at 10 or 20, and at some point more miles provide diminishing returns. We’ve all experienced the reduced rate of progress after the heady first few years. Whether this is devastating or not depends primarily on expectations generated by parents, coaches and peers.

A runner who has done significant miles at 10-13 isn’t likely to improve as much from 14-18 as one who is just starting at 14. They may, however, be able to compete more healthily at a top level during that time because of their early miles. Mark Hadley points out that, even if Alana doesn’t get any better in high school, she’s going to be one of the fastest if she continues running the times she runs now.

While Hadley is an outlier, most kids can safely do many more miles than they’re doing now. Bill Hackney, a successful middle school coach in Marietta, Ga., says, “My goal was to always have my oldest athletes be at the point to where they could comfortably cover 50 miles a week in training on a six-day-a-week schedule by the time they started their freshman year of high school. This would allow a knowledgeable coach to easily get them up to about 70 miles per week by the time they reached their senior year of high school.”

That Alana will continue to improve isn’t a given, but it should be noted that for all the examples of runners who didn’t advance after running a lot early in life, there are those who continue to improve and excel. Dathan Ritzenhein started training in sixth grade, has been doing 100-mile weeks since high school and not only has no regrets but believes it’s the only way one can be competitive. Amy Hastings worked up to 80 miles per week by the end of high school, where she won three Kansas state titles in cross country and track. Far from regretting her earlier mileage, she remembers it as “so much fun” and credits it with an easy transition to Arizona State, where she was a 10-time All-American and won the 2005 indoor 5,000m title. At March’s LA Marathon, she debuted in 2:27:03, making her the eighth fastest American in history.

One other risk is overspecialization. Similar to adults, if young runners do nothing but sit except when running, they’re likely to get injured and not develop their full potential as runners. While kids, like their adult counterparts, can perform drills and strengthening exercises to counteract this, too much of this takes running away from the play it should be. Most argue that it’s better to have them active in a variety of physically demanding sports.

Larry Greene and Russell Pate argue in Training for Young Distance Runners, “When track season is over, they should participate in soccer, basketball and other youth sports, because it is important to develop all-around physical fitness before beginning specialized training for track and cross country.” Olympian and sports physiologist Pete Pfitzinger agrees:

“If a kid plays a variety of running sports (soccer, basketball, lacrosse, etc.) from ages 6–12 and does some 20-to 30-minute runs during that time, then he or she is preparing the bones, ligaments, tendons and muscles for more regular training.” Noakes, while citing all the research referenced above that running won’t hurt kids, believes “intensive and focused training” should ideally wait until kids are out of school.


In a context where kids don’t regularly travel more than a block by foot and don’t often play actively, few are physically prepared or motivated to run nearly the miles of Hadley. Thus the majority of youth coaches rightfully focus on developing good technique and building strength and aerobic capacity through gradually increasing moderate distances.

Given a runner with a strong desire, good biomechanics and the patience to build over years, however, we shouldn’t fear when a child runs more miles than most adult marathoners. Even with concerns over motivation and external pressures, it’s a rather strange commentary on our society that a runner doing more than expected generates as much or more health concern than her many peers who are overweight.

“They are more likely to have problems being obese,” says Hudson. “There are worse things hurting our country than kids running too much.”

Most importantly, children should be active: The African advantage has more to do with extensive daily activity than specialized running. A child outside playing for hours each day will be better prepared than a sedentary one who goes to a daily one-hour practice that includes 20–30 minutes of instruction. Running can be play, even for a 10-year-old, as it is for all of us adults who continue to do it for decades.

The key is that each runner is individual. The answer to whether a 12-year-old runner should do a certain mileage is always: “It depends.” The parents’ and coach’s role is to provide a caring context and by all means not to push or pressure–but we needn’t discourage either. Mark Hadley notes, “We say that the reason American runners are behind is that they are 10,000 miles behind the Africans by the time they get to high school. Then you have someone who actually isn’t going to be 10,000 miles behind and we say, ‘Whoa, hold on now…'”

Alana is still an experiment. No one knows if she’ll go on to high school and collegiate success, like Jordan Hasay, or will have leveled off, gotten tired or accomplished her goals by the time she’s 18. For her part, she’s just eager to get to her next run.


Not Built In A Day

Key to running more miles is building your totals over time. While Alana Hadley’s current 70 miles per week raises eyebrows, she’s built this gradually over eight years of running, a more sensible progression than most adult runners use.


6 2-3 times a week 4-6 miles all easy pace 29:13
7 3-4 times a week 5-10 miles all easy pace 25:35
8 4-5 times a week 15-20 miles mostly easy, occasional fartlek 23:53
9 5-6 times a week 20-25 miles occasional fartlek or short tempo 21:07
10 6-7 times a week 30-35 miles introduced long runs 19:17
11 6-7 times a week 35-40 miles good mixture of speed work, tempo runs and long runs 18:12
12 (first half) 7 days per week 42-46 miles good mixture 17:35
12 (second half) 7 days per week 47-52 miles good mixture
13 (first half) 7 days per week 53-58 miles good mixture 17:09
13 (second half) 7 days per week 62-67 miles good mixture
14 (current) 7 days per week 70-75 miles good mixture (hasn’t raced yet)


Girls, Weight and Self-Esteem

One exception to the assertion that miles can’t do long-term damage to a child comes when the running is accompanied by inadequate fuel. “Female runners who do not take in enough calories may have an ‘athletic energy deficit,’ which commonly results in stress fractures and can cause long-term health issues,” Marc Bloom writes in Young Runners. These health issues, often lumped into a syndrome called the female triad, can include amenorrhea, anemia, stress fractures and osteoporosis.

Complicating this syndrome is both the cultural mandate to be thin, and the fact that the onset of puberty results in a weight gain of 10–20 pounds on average and often results in a slower runner. Not only are health issues involved, but this transition can be traumatic for a girl who has built a self-esteem as a runner. Olympian Lorraine Moller says, “It is extremely important that the woman needs to develop along with the athlete. Stages of development can be a crisis. A poor body image can really be imprinted very deeply.”

None of this means girls can’t or shouldn’t run long, but particular care must be given at every stage. Coach Jay Johnson argues, “I think for girls a triad between family, coach and doctor is needed to actively keep the female triad away.”