figure out also. Why train kids? We just heard some good reasons why to train kids. But sometimes our wishes and our goals confront reality and some of the inner city kids don't get this opportunity, as we all know. Not to beat the drum very hard, but inner city kids in Boston, for instance, most of them don't know how to swim. They live four miles from the ocean, et cetera. So we've got some problems. So exercise training for youth makes them healthier. It can enhance sport performance if they're involved in sports. And of course this is a sports medicine symposium. And of course it can help prevent injury. Properly done and properly followed out and followed up by the parental people and the coaches and so forth. We'll talk about it in some detail. So these are some two kids doing free play activities. And those of you who haven't ever seen this, there are films of this in the Smithsonian Institute. Because it's happening less and less, as a matter of fact. And frequently and increasingly, what exercise kids will get is coming in the organized sports situation in this younger age group. And that's a variety of reasons, fear about neighborhood violence, parental concerns, schedulization of the kids' times and so forth. We won't belabor that. But we now know that in both team sports and individual sports, we have tremendous organization. There can be deleterious effects. We've heard about gymnastics. And we see that certainly on our young dancers and on occasion and so forth. You can have too much training. So training we're talking about, properly done, may be able to prevent injury. It's also a risk factor for injury, maltraining. And we'll see that repeatedly. And I'm just going to go back a second to give some historic perspectives for youth training. The origins go back, obviously, to ancient Greece. Herodotus was a sports trainer who then became a physician. But in the Boer War in Africa, people were struck at how unfit the young people going into the British military were to fight the war. And that was the origin of the Boy Scouts movement. And this carried on in the United States in the sports training and fitness programs of the presidential consuls. And the kids got points for doing physical activity and so forth. And unfortunately, this whole approach has fallen upon hard times. And I attended a symposium at the American College of Sports Medicine about a month ago on fitness testing. Okay? And there were four world experts on fitness testing. The bottom line was the kids were not very fit. And most of them didn't do well in the testing. So I got the hidden conclusion that we were going to discontinue testing of children's fitness going forward. Okay? So there's a problem somewhere. Here was Arnold Schwarzenegger when he was the chair of the President's Council on Fitness and Sport. And I was our state chair for fitness and sport for kids. And he came and visited every state during his tenure to promote this idea. And it's almost gone now. There are no longer state, by and large, state committees for fitness and sport. Prevention in sports. One of the early papers from the American College of Sports Medicine we were involved with. I think one of the earliest points on sports strengthening, strengthening to prevent sports injuries, and we're going to hear about that in some detail from Dr. Axe, was Charlie Hayner's paper from Illinois. And he talked about the prevention of sports injuries in high school students through strength training. And up until then, people who did strength training were doing it to sort of general fitness or maybe for competitions and so forth. But kids weren't lifting weights. When I played high school football in Illinois, we didn't even hear of a weight. Okay? Of course, we worked on farms and stuff like that. But the whole idea that you would do a systematic training of the strength of these young athletes and hope to prevent their injuries was a new one at that time. Again, to give some historic perspective, early on, organized sports in the United States were, by and large, university-based. Rowing, 1876. Good iron football evolved from rugby football in the 1890s. And the physicians involved in this whole area of looking at organized sports by young athletes, primarily college-age athletes, kids weren't playing organized sports then. Okay? Here's the Harvard track team. Augustus Thorndike, to my knowledge, published the first book on sports injuries. And the first section of his book, he did it three different volumes, was on prevention of sports injuries. That was his first entire section. Then he went into the individual assessment of sports injuries and then how to treat them and so forth and so on. He talked about training regimens for these athletes. He talked about the introduction of special diets for them, mandatory protective equipment. And he introduced the concept of athletic trainers to assist in the care of the athletes. So it started with the university programs and then worked down to our present concept. In the United States, Little League Baseball started in 1947. That was the beginning of this whole thing we talked about a few minutes ago, the whole development of these organized sports for kids. And here's a situation we run in with, too. I take care of a lot of figure skaters and dancers, and I will have families move from across the country so the kid can get a specific coach for figure skating. It's amazing. So that has gone on, and we're not going to change that much. So in 1971, 7.2% of high school girls played organized sports. As we all know, this is the fifth year of Title IX also, in addition to the AOSSM. And now, as we all know, organized youth soccer, there's more girls playing organized youth soccer than there are boys now in the United States, et cetera. So with that has come the growth of sports injuries, the concern about the gender specificity and the increased rate of injuries in young female athletes. I think it's an unsolved problem. My younger daughter played for the United States women's rugby team, tore both her ACLs, and she was in shape, and she was lifting irons. So we still don't know why this is. So we have to use epidemiology. And basically, most of us are drugged into epidemiologic approaches because kicking and screaming, because we were used to just dealing with the phoenix of one patient at a time and so forth, not numbers of patients. But it has been very useful. And it's an essential tool for if you're going to do injury prevention interventions in particular. It helps us determine the etiology of patterns of injury, control methods, game versus practice, look at risk factors. This is age, gender, position, and so forth. And finally, it's absolutely essential for prevention. And the incidence of injuries, injury surveillance systems are the front line of this whole epidemiologic approach. It's the kind of thing that no one wants to do, so the athletic trainer generally has to do it, keep track of the injuries and rates of injuries and so forth. Relative risk for exposure, and the ideal is per hour. The NCAA still does it through athletic exposure rather than hour, so the data is somewhat difficult sometimes. And look at the effect of safety interventions. So organized sports for children, benefits versus risks. They certainly allow some kids, what little exercise they're going to get, they're going to get in an organized sports situation. On the other hand, there's this potential for injury. Children's age 5 to 14, the tremendous, the younger ones have a higher rate of injury, actually, than the fully-discovered adolescents that we've heard about. Dorothy Daymore's study showed 41 percent of the kids who came into the emergency room at Presbyterian had sports injuries. We all see this now in our EWs. And the incidence seems to be increasing. So just to talk a bit about risk factors, and one of them is, as you see, is training and environmental. This was our more traditional approach when we first started analyzing and trying to do studies on why this kid got this injury. We looked at host factors, environmental factors. And more sophisticated now, it's been listed as extrinsic risk factors and modifiable and non-modifiable extrinsic risk factors. And potential modifiable is fitness level in the most general sense. And then, of course, how they train to get that fitness level or sometimes overtrain. So as a host factor, muscle, tendon, and balance, we've heard about how this can occur, and the entrance to adolescent, and during these different growth spurts that can occur at different times and so forth. And certainly during a growth spurt, as an example, the ITB is very strong. They tend to get a tendency toward valgus alignment. Eight-year-olds, we've got a skyline view of the knee. Kneecap is usually very symmetrical, sitting right in the middle. Medial and lateral facets are equal in size. That same kid, some of them, at age 14 now have the risk factors of anatomic deformation of the extensor mechanism as a result of growth. So this is something we have to look at much more effectively and in a more systematic fashion. Now ballet, as an example of an additional discipline, which adds muscle imbalances. The ballet dancer is doing a lot on their foot in a pointed position, and most of their activity is up and out, up and out, up and out. Vastus lateralis gets strong. The vastus medialis is relatively weak. The gastric is strong, and the dorsiflexions are weak. This was once one of our studies. We looked at it. These are young adult female dancers. The quad-ham ratio, or ham-quad ratio, if you will, is pretty much what you see in a lot of different athletes. But the dorsiflexion, plantarflexion difference is rather dramatic, and we think it contributes to some of the tendinopathies we see in the young dancers who try to emulate the older dancers. So again, an example of muscle imbalance as a risk factor. This is looking at soccer players versus figure skaters, and we see that, as in the next slide, the ham-quad ratio, which has been shown to be an important factor perhaps in the occurrence of ACL injury, is much better in the figure skaters, even at a younger age and so forth. We know from epidemiologic studies that ACL injuries in figure skaters are extremely rare as opposed to soccer players. Now, there are other factors, too, the extrinsic factors, such as field and shoe wear and so forth and so on, but this may be a factor, that the activities they're doing result in a better ratio of ham to quad. The fitness level, in a very basic sense, are they fit or are they not fit? And basically, you may have seen the article in which he looked at the body mass index of interalignment versus backs and so forth, and found that there was a good assessment of relative cardiovascular fitness in kids. And again, training as a risk factor, because I'm saying intervention with training can improve fitness in so doing, decrease the rate of injury in many sports injuries, but it also can be a risk factor. How much is enough? How much is too much? And this is an adult study. This was a running study, Mike Pollack, okay, training at 70% of VO2 max, 40 minutes, four times a week, 12% rate of injury. 85% of VO2 max, 15 minutes, three times a week, 22% rate of injury of overuse injuries. And 85% of VO2 max, 45 minutes, three times a week, which at that time was recommended by the American College of Sports Medicine, 54% rate of injury. So, mal-training is unfortunately something we must continue to try to detect and avoid. So, over-training the young athlete, it can affect performance, it can obviously result in fatigued states, it can affect growth. We see this young gymnast, it tears her ACL, and her growth goes ving, during a time when she should be catabolic. Training 24, 28, 32 hours a week has inhibited her growth, and of course, finally injury. So stress fractures in kids, we never saw them until we started having systematic training as a preparation for sport. 38 of the 41 women, at the first women's class at West Point, 38 of the 41, at the end of the six-week training program, had stress fractures. Mal-training. Or perhaps lower levels of fitness, or a combination of the two, of course. So volume and progression, 20 to 22 hours a week, we think the maximum the kids should train in any sport activity, and the 10% rule of increasing the volume or intensity of training, 10% per week. You run 20 minutes three times a week, you run 22 minutes three times a week the next week. It's a way of preventing over-training injury. Conditioning, and of course, most of what we're talking in this session is musculoskeletal conditioning. We're not talking about cardiovascular, vascular, we're not talking about body composition, and so forth, we're not talking psychology. Strength, flexibility, and endurance, the characteristics of the musculoskeletal training, each one of them can be a different component, and to neglect one is to sometimes still result in problems. And finally, as a risk factor, the environmental coaching. So here's a typical coach in this age group that we're talking about, the prepubescent with open growth plates, a well-meaning volunteer. He's got two hours with these kids, and he's supposed to teach them how to play soccer so their parents will be happy that they won a game. But he's also going to do a half hour of ACL prevention training, every one of those practices. Possible, not probable. ACL prevention programs, we're going to hear a lot about that from Greg, I'm sure, but one of the key components when we looked at these different programs and reviewed the literature was compliance. The coaches have to buy into it, the parents have to buy into it, and then it'll be effective. And there were several studies that did not show a decrease in ACL occurrence with pre-prevention interventions. Often when you really analyze what the kids were doing, they weren't doing much. Okay? So 2015, we looked at that, age start early, biomechanics, we'll talk here about the dosage duration, the actual exercise the kids do, and of course, feedback to the kids about, you're doing great, et cetera, et cetera, et cetera. So strength training. Hamstrings. We think that the hamstrings are the most important. The hamstrings are the friend of the ACL, and almost any strength program should have a definitive attempt to increase the hamstring strength. We send kids to trainers sometimes, or sometimes BTs, and they come back and their quads are like rocks and they're still weak in the hamstrings. Neuromuscular training. Biometrics. We've seen some nice illustrations from Lynn about the very simple things one can do, rather inexpensive things one can do with these kids as far as the components of your whole regimen. And techniques of cutting, landing, and agility. One of our colleagues who's now passed on used to always talk about, teach the kids the two-step cutting technique as far as one of the techniques of preventing these injuries. Bracing? Probably not. Okay. Now in closing, one of the things we sometimes don't think about too much is that when you do consistent, regular training of your musculoskeletal system, and you get stronger, the bones get stronger, the muscles get stronger, and so forth, you can get this in a variety of ways. My grandmother, who grew up in a fishing village in Spain, I don't think she would have torn her ACL if she was playing soccer as a 14-year-old. But she worked physical labor, functioning every day of her life. When she was in her 60s, she could pick up a half-washed cup full of coal, put it on her head with a towel on it, and walk along smoking a cigar at the same time. And I have a feeling that her ACL, if you tested her, would be pretty strong. This is a study that Dr. Voytich and her colleagues have done, showing that asymmetric activity in certain sports, such as skating in particular, demonstrates the increased size and presumptively increased strength of the ACL. So again, the most basic thing we can do is strengthen their tissues so they don't sustain injury. The IOC had a consensus statement on training the child athlete, which I had a part in, and so forth. It basically ensured the sports programs are fun for the kids, educates the coaches, a great goal, of course, improve the quality of the sports programs. And for health care systems, mandatory education of our health care personnel, get our health people out into the fields. Inner-city schools have a low rate of athletic trainers, which we've, in Boston, we've tried to train that. We've gotten funding for it. And every school now has an athletic trainer. Revise the health care financing to emphasize reimbursement of prevention techniques, and use objective measures of physical activity. So participation in sports is something we all want to have happen. It's becoming increasingly important for the kids as their other sources of exercise disappear. And so I think we have to do everything we can to make it safe. It's a brief bibliography. Thank you very much. One question for you. You mentioned the stress fractures, and I know you've seen and dealt with a lot. In kids, is it really the deficiency of muscle and inability to protect the bone? Is it really the bone deficiency, or is it a combination of those? Probably a combination, but I think most often it's inappropriate training. You've got someone who's coaching them, who's got the old whistle going, and having a kid who's been relatively sedentary suddenly is doing too much. So it's a sudden increase in the body. It's maltraining. So if you know the kids are going to be doing that, can you change that paradigm by resistance training? And how early is it safe to start that in kids? I think the resistance training is the one thing we can do to make the tissue stronger and so forth. You can safely do strength training. As soon as they can do cognitive activities, and that's usually the age of school, age 5, age 6. We've started programs, and Avery Faganbaum, our colleague, and I myself have worked on programs based at the Y's, strength training programs for kids, and it has a lot of multiple benefits, including psychological. Great. Thank you.

training and conditioning

children

sports

risks

injury prevention

youth training