In Part 1 I covered the scientific support for children participating in strength exercise. I also defined terms used to describe different categories of strength exercise such as weightlifting, powerlifting, bodybuilding, strength training, and movement categories. If you didn’t read part 1, hop on over.
In this post I want to cover some important principles to understand about physical training in general, and training children either for sport or for fitness.
A knowledge of these principles will answer the majority of the questions you might have about training “fitness” in children. I feel comfortable saying this, because while I could tell you what exercises to do, or what program is “good” for this or that, that’s not actually helpful to you, unless you hire me. A lot of coaches feel this way. You can’t just hand someone a program and say “it will do this”. A program is really an organized series of best guesses, based on principles and laws we know to work for developing different aspects of “fitness”, both for sport or health, but more importantly, a good program is as individual as possible.
The good news, is that understanding the principles yourself, will show you that you can answer your own questions or narrow your search down much more accurately on your own. It will help you ask better questions as a parent or coach, which is the only way to get better answers.
First of all
Kids are not little adults. They are growing. That is another “duh” moment for you, but it’s funny how sometimes the most obvious things are forgotten when the time to apply something comes along. While kids can strength train, the how and the what needs to be very appropriate for them. That’s what we will delve deeper into here.
For clarity’s sake, when I refer to children and adolescents, I am referring to the ages 0-16. Development varies, so this is a generalization. But after the age of 16, the body (both structurally, hormonally, and mentally… well, that’s debatable, but in terms of being able to process, focus and execute more complicated movements and instructions) is close to being fully developed or closer to its permanent adult structure. So for our purposes, when speaking of “kids” lifting, the 0-16 age range is under discussion.
Children and their developmental stages can be loosely divided into age categories, with about a year discrepancy between males and females (females develop quicker). After reviewing several resources, for simplicity’s sake here are the basic age categories:
0-7 – Very Young
8-10 – Young
11-13 – Pre-adolescent
14-16 – Adolescent
16+ – Adult
When reading over any of this advice, please apply age to the context.
The following sections of this blog post are:
1.) The principle of GPP (general physical preparedness), play, and motor learning (developing movement)
2.) Specializing in sport at a young age; the discussion
3.) Practical takeaways for parents and coaches
The principle of General Physical Preparedness (GPP) and play
Here’s a baby doing a plank. Except this baby didn’t have to be taught to plank. It’s something that occurs naturally on his way to walking. That process by which this happens is called developmental motor learning. This is also the cutest baby boy on Facebook. The kind that makes me unlike his photos, just so I can have the pleasure of reliking them. I want to eat him up.
Babies: from quivering blobs to executing the perfect squat
“During the first two years of life, babies develop from a quivering blob on the floor, to creatures that can roll over, sit, crawl, squat, walk, and manipulate objects and drive their parents crazy. The rate of motor learning is extremely fast and very impressive. Toddlers squat with the perfection of Olympic weightlifters. Their head carriage and posture would please any physical therapist. And their movements have the grace and simplicity of a Zen monk. The amazing thing is these optimal movement patterns emerge without any instruction whatsoever.” (1) – Todd Hargrove, A Guide to Better Movement
Quivering blob! That cracked me up. Little jelly legs and tummies. Yummy, yummy. But I digress…
Bet you wish you could plank like this don’t ya? Fact is, if you plank, you are actually trying to get back to the “ease” with which this occurred. Except now, you are older, heavier, and planking requires more strength relative to your movement skills. This baby isn’t stronger than you per se, but he is stronger than you relative to you. He can control his bodyweight, and soon he will be squatting in ways that make you cry and wish you could still suck your toes for comfort.
This is where all this “squat like a baby” stuff comes from, except the underlying concept gets lost in the reductionism (just like basically all memes online). People end up arguing about whether “everyone should squat like a baby.” You’re not a baby anymore, so that’s a dumb question.
A better question is: Why do babies squat with such ease, and how can we apply what we know about how our bodies’ development movement from being blobs to little runners, so we can get better movement for ourselves and then load/accelerate/whatever that movement to get fucking stronger or faster?
Back to the point: kids don’t need to be “taught” to move they just need to be given opportunities to move and a varied and engaging environment to do it in. This is how all bodies learn movement, we just learn faster, smoother and better when we are kids. Childhood and adolescence is the prime time in life for learning. And moving is learning. Physical literacy.
The floor is our start! Then getting to the kitchen cupboard to wreak havoc. Monkey bars? An older brother to wrestle with? Kicking a ball?
Motor control is defined as “is the process by which humans and animals use their neuromuscular system to activate and coordinate the muscles and limbs involved in the performance of a motor skill.” – Wikipedia definition
A motor skill is (or motor skills are): “A motor skill is an intentional movement involving a motor or muscular component, that must be learned and voluntarily produced to proficiently perform goal-oriented task, according to Knapp, Newell, and Sparrow.” – Wikipedia definition
Playing guitar = motor skill
Picking your nose = motor skill
Dribbling like Neymar = damn well developed motor skill
Squatting = motor skill
Squatting a fuckton = still a motor skill
Flexing your bicep on demand = motor control of bicep
Twerking = motor control of glutes, motor skill to do it as you come down in a squat
My fave example of this is the movie Karate Kid. The new one with Will Smith’s son. Where he has him take off his jacket and remove it 1000 times before he shows him how that translates into a kung-fu skill. This clip shows you the gist of what motor learning/skill etc is about. Pretty cool when you think about it. There is no way Dre would be able to develop speed and power in his “removing jacket” motor pattern (which turned out to be Kung Fu), unless he first practiced it enough and created that “movement map” in his head:
Children start off with poor motor control and as they grow develop better control of the musculature that moves their limbs. They shit themselves, drool, smack you in the face on accident and then grow up to run away, flip you off and gyrate in clubs. Clear advancement in motor abilities.
For an actual instance though kids cannot control holding in their pee and poop till the hip and core muscles are developed enough to do so, and that strength is developed as they learn to squat and then stand. The squatting literally “tones” the muscles of the pelvic floor, legs and hips so that it can hold it in voluntarily!
They start “learning” that squat pattern by trying to stick their foot in their mouth while still on their backs. Until a child can squat and then stand, the muscles for holding their pee and poo in, aren’t strong enough to do so. The squat develops the muscles that eventually allow them to control their bowels. So not much sense in trying to potty train them super early anyway then, eh? Also this can tell you a lot about urinary stress incontinence in women after pregnancies (or just normally) and why proper squatting is a “cure.” Always wanted to share that tidbit.
To continue, the rate at which children develop is quite variable. Some walk sooner, some later. That’s irrelevant, but it’s also why your pediatrician has a chart of the averages to compare you kid against. Severe delays can indicate something is wrong.
Everyone can probably think of examples of some awe-inspiring athletic child back in the day. The one who could outrun everyone and seemed so coordinated. You can also imagine the less athletic kids, the “motor morons.” The ones who tripped on their own feet and got hit in the face by the ball they didn’t catch fast enough.
That really doesn’t matter though. You can’t control the genetic makeup your child ends up with, so it’s not worth stressing about. But you can control the environment and exposure to stimulus, and that is where the seeds of strength and athleticism start.
ALL KIDS need movement, play, and challenging fun, even the ones that turn out to be superstar athletes. In fact it might be more important for them, since they are often the ones who burnout or get injured faster due to early specialization in sports and over-zealous parents and coaches. But that’s the next section.
What are some examples of motor skills we learn as young children (ideally)?
The textbook Developmental Physical Education for all Children says:
“We can view the entire period of childhood as a sensitive period for mastering fundamental movement skills and for being introduced to a wide variety of sport skills. Especially important is the period of early childhood – roughly from age three to eight. The development of mature, fundamental movement skills is a prerequisite to the learning and mastery of sport skills.” (2)
So all this “mastering movement skills” means your kid needs to play and play in lots of different ways! Here are a couple charts, to give you a visual. While looking over it, you can easily see how sports and recreational play covers just about everything.
While we think of sport skills as relating to a specific sport, you can (for the sake of context) include lifting weights as a sort of “sport”, since this series was originally about the question “Should my kid lift weights?”. I know it is not if you only do it recreationally, that’s not the point. The point is that lifting weights is specific as well. Lifting weights, and training for strength is often MORE specific than it needs to be, and introduced in higher specificity (just the barbell lifts?) before someone’s body has a good movement base to begin with. A movement base is broad, and that variety is important to develop as a child, whether they will become an elite athlete in one sport, or just stay strong and mobile till death. I think it is safe to say that the reason we need so many corrective protocols, variations, regressions and progressions etc, is because we are trying to regain what was supposed to be ours from the beginning; easy, graceful and varied movement, that can eventually be loaded, sped up, trained powerfully, or evolve for high specificity for a sport.
So the goal, is not A squat, the goal is to be ABLE to squat.
Building a solid athletic base
Certain sports develop fundamental movement skills better or with more variety than others. Gymnastics and wrestling/judo require more tumbling, pulling, rolling, flipping etc. In my personal opinion, they are the two of most valuable sports for children, especially from a young age. Track and field sports also encompass a variety of skills. Jumping, bounding, sprinting, running, and throwing. The importance of variety in movement for children is a common theme you come across.
The “Longterm Athlete Development Resource Paper” (3) published by Canadian Sports Centres, lays out the framework for proper development and stages of (physical and psychological) development from the ages 0-19+. They categorize the building blocks (those basic motor skills!) of more specialized movement by calling them FUNdamentals (see the above pic). And that’s a good way to remember them, because it enhances one of the most important principles for learning physical skills: fun and play. Kids learn from fun and play.
“The basic movement skills of 3 activities provide the base for all other sports:
- Athletics: run, wheel, jump or throw.
- Gymnastics: ABC’s of athleticism — agility, balance, coordination, and speed.
- Swimming: for water safety reasons, for balance in a buoyant environment, and as the foundation for all water-based sports.
Without the basic movement skills, a child will have difficulty participating in any sport. For example, to enjoy baseball, basketball, cricket, football, netball, handball, rugby, and softball, the simple skill of catching must be mastered.” (3)
You can eventually perfect, load, or specify movement for a sport as a child grows, this is what appropriate means. And this is where kids can also engage more and more in what we might think of as “formal” exercise, or sport-specific skill training.
But the best thing you can do for your kids physical fitness for sport or health is create an environment where daily physical activity is the norm, and provide them with opportunities for play with a variety of tools and tasks. Beyond that, everything is possible. Kids can lift kettlebells, train Olympic lifting, or bodybuild in the basement with you. They can take classes, try out any sport they like, and ride their bikes to death. Street soccer and hockey is a good idea, as is climbing trees and rolling down hills. Building a solid movement base, especially before the pre-puberty years of 11 and 12 is a crucial time for building physical literacy and a solid athletic base.
Play and physical exertion is becoming less normal to kids. Video games, TV, shorter recess, homework, less P.E. and home environments (parents, that’s you) that don’t encourage physical activity, are eroding the caliber and quality of health in children, and the adults they become.
“Here’s our reality. Kids don’t move. Gym is gone and the concept of outside play is all but dead, which is where children used to develop their GPP (general physical preparedness, or basic motor skills).” – Ryan Burgess talking about developing skills in kids for sport (4)
“With the high incidence of childhood obesity in the Western world, many children cannot do simple pushups, pull-ups and sit-ups. It has been shown that even body weight exercises are difficult to perform, and the inability to perform an exercise dramatically affects the child’s desire to exercise due to negative feedback (“I can’t do this”) and self-esteem. The ability to handle one’s body mass is vital to optimal athletic performance, and weight training exercises should be used to reduce the loading and improve the base fitness levels of younger athletes so that they can develop the ability to control their body mass in exercises. Progression in various machine and lifting exercises can help develop body mass control and movement, a critical feature of athletic performance.” (5)
Motor skills and motor learning is not talked about enough in regular “fitness” in my opinion. At least, I don’t think so. It’s pretty simple. Every movement you have is a motor skill. It is learned. HOW it is learned is very important, and a whole ‘nother tangent I won’t go off on right now. But in bringing this back to children, and lifting and physical activity here’s what you need to know; the optimal time to build the foundation for everything in life is during childhood, including physical health, movement and prowess. Sobering eh?
Now, on to the next topic.
Too early, too soon? The discussion on specializing early in one sport, and sport-specific training
I am not the most qualified to talk about this, but I do know a lot of coaches who are and have read a lot of their work. I did spend two years working with high schoolers but have never coached a sport specifically. I feel it is important to say that, since some of the ideas I will present are well-supported but controversial, especially to coaches and parents who have dreams of their kid being a superstar athlete. If you have a kid like that, this is even more important for you to read.
Developing athletes: don’t build an upside-down pyramid
Someone referred me to a great resource written by Gareth and and Leigh Ashton called Youth Training 101 – The DASH Method. You can purchase it here. They describe the issue well by distinguishing between developing athleticism and developing an athlete. In their words:
“It’s important we clear the air between Athletic development and Athlete development. The terms are often used interchangeably, but hold very different meanings. Athletic development relates to developing someone’s physical abilities or ‘athleticism.’ This includes locomotion, stabilisation and manipulation skills such as how they run, jump, change direction, turn, combine movements, lift things, throw, kick, catch, and many others. It also involves the components of fitness such as speed, strength, power, endurance and coordination. The broader term of Athlete Development covers all of the components that are important to succeed as an athlete in the arena of sports. This includes athleticism, sports skills, game sense and tactical understanding, personal character traits, mental and psychological skills, knowledge and application of nutrition and recovery strategies. Athleticism is a crucial (and often over-looked) component of overall Athlete Development.
“Fundamental athletic capabilities form the foundation of effective and injury free movement and performance both in sport and general lifestyle activities. The more athletic someone is, then the greater platform they have to develop specific skills and capabilities and achieve at the highest level. Athleticism establishes the base of ANY sports or fitness environment, with all of the other components forming layers built on this foundation.”
AKA? Don’t put the cart before the horse. Or as Ryan Burgess says “don’t flip the pyramid on it’s head.”
Excelling in one sport too soon: making kids prone to injury?
The problem is that often sport-development (in the USA especially, from all my research) does not respect this process. There is an early emphasis, not on development, but on specializing and excelling in one sport too soon (again, from all resources this means prior to age 11/12). Kids peak in their sports too early by their late teens, are worn down with injuries by college (ACL injuries in highschoolers!), and have no longevity in their sport and leave athletics with a lifetime of consequences. Some sports peak at an earlier age (gymnastics for instance), others later (pole vaulting is an example), but this concept still applies for the most part. The main point is that the developmental years for a child, should be just that: developmental.
“This is the model that ideal athletic skill and performance is built upon. A solid foundation of GPP will consist of gross motor skill mastery, proficiency in relative body strength and the introduction of general strength training, and a healthy level of cardiac fitness… basically, getting good at the things a functioning human should be good at. SPP is where we begin to get more specific towards our individual goals: planes of movement, dominant energy systems, special strength training, etc. Finally, Technical-Tactical Preparation is the chosen sport itself.” Ryan Burgess (4)
GPP = general physical preparedness. All the stuff I have been talking about above. Kids jump into highly “sport-specific” training without a good base. Sounds like a lot of adults too.
“Under-prepared children exposed to inappropriate developmental stressors is a recipe for injury, poor performance, and inadequate skill development. When dealing with youth athletes, the developmental aspect of the equation is paramount.” – Ryan Burgess (4)
Read Coach Burgess’s post in full here.
“Sport-specific” is often a money term. It really only applies if the basics are learnt and covered first, and the kid has a proper movement base. Sport-specific is anything that makes you a better athlete in your sport. And sometimes that will be a pushup… not a fancy drill. It will be goblet squats, not “plyometric-agility-rapid-fire” drills. You see so much of that stuff sometimes. Parents want to see their kids “working” and mediocre coaches emphasize “no pain, no gain” and train kids for speed, power or strength irresponsibly on top of demanding and regular practices. This can break down a kid’s potential early, and expose them to unnecessary injuries.
Developing Long-Term Athletes
Canada Sports Centre’s LTAD (LongTerm Athlete Development) model uses FUNdamentals in movement as one of their guiding principles, as I mentioned earlier. About their methodology, they say, “LTAD is an inclusive model that encourages individuals to get involved in lifelong physical activity. It does this by connecting and integrating physical education programs in the school system with elite sport programs and with recreational sport programs in the community. LTAD ensures that all children correctly learn the fundamental movement skills — since all children attend school — and that these skills are introduced during the optimum point in their physical development, which is prior to age 11 for girls and age 12 for boys.” (3)
“With sorrow, the chase after high sports achievements at an early age leads to the fact that for many athletes, it becomes necessary to correct errors acquired by them in the early years, even on the level of high sports mastery. In order to do this, much time is lost in the first two stages of multi-year preparation. In most cases, it is not possible to make the changes. As a result, the ineffective technique used, based on the degree of improvement in this sports result, becomes more comfortable rather than trying to acquire effective technique. The sensations instilled from ineffective techniques remain for one’s entire life. To eliminate them is practically impossible, as is changing them to some other more effective ones.” – EliteFTS article Review of Explosive Running by Anatoly Bondarchuk (6)
“Early focus on competition is a short-term solution, which does not bode well for the long-term athletic development of most young athletes. Parents and coaches may encourage sport specialization too early, not knowing that they may actually be causing the opposite of the desired effect. Early specialization involves long, organized, strict, sport specific practices which children often do not find fun. This can cause the young athlete to lose their original love of the sport, feel pressured, and ultimately dropout of sport participation, even if they are very talented…..At the age of 13-15, athletes are old enough to understand the commitment that being an elite athlete requires, and they can make the choice for themselves as to whether or not they want to make that commitment, or just continue to play sports recreationally.” – From Youth: Early Sport Specialization (7)
Zatsiorsky sets out this timeline regarding strength training specifically in Science and Practice of Strength Training:
Table 101: Basic Guidelines for Resistance Exercise Progression in Children
7 or Younger – Introduce child to basic exercises with little or no weight; develop the concept of a training session (fun is of primary importance!); teach exercise techniques; progress from body weight calisthenics, partner exercises, and lightly resisted exercises; keep volume low.
Notes: Weightlifting technique for the clean and jerk and snatch can be started as soon as a child can pay attention and hold a pipe mock barbell. As young as 3 or 4. Weight is always relative, and children learn good movement skills during this age through play. It’s not complicated; just make sure they are not strapped into jonny-jumpers and walkers nonstop. Or worse, just sitting on their bum all day watching kids’ TV because they “like it.”
8-10 – Gradually increasing the number of exercises, practice exercise technique for all lifts, start gradual (and appropriate) progressive loading of exercises, keep exercises simple, increase volume slowly, carefully monitor toleration to the exercise stress.
11-13 – Teach all basic exercise techniques, continue progressive loading of each exercise, emphasize exercise technique, introduce more advanced exercises with little or no resistance.
14-15 – Progress to more advanced resistance exercise programs, add sport-specific components, emphasize exercise techniques, increase volume.
Notes: Any kind of SnC training should NOT come close to leaving a child exhausted, beat up or excessively tired and drained. If this is a regular occurence, check in. Especially if your kid also plays a sport. This is the age where a child may benefit from, and be able to follow properly, a more formal lifting program. Westside for Skinny Bastards is an example.
16 or older – Enter adult programs after background experience has been gained. (5)
Takeaways for parents (and coaches)
So after all that, here’s some practical advice for sport development, specifically:
1.) Young kids need to play. Encourage that liberally and in as many ways as possible. This will build the athletic foundation needed to excel in sport. Any sport.
2.) Sports are good. But pushing sport-specificity too early can be damaging physically and psychologically to a child. Always have longevity in a sport and your child’s health in mind. Your kid is your job, no matter what some overzealous coach might say. Very few middle schools or high school have strength coaches. Middle schools will have physical education teachers, some great, some not. Sport coaches are not strength coaches. Your kid might need help getting fit for their sport and preventing injury, but allowing variety and physical activities that are purely recreational can also help the balance.
3.) Here is some help in finding a good strength coach, class or exercise experience for your child:
- Ask them their approach to teaching beginners, and kids that have never used weights before. If they put a big emphasis on safety, technique, and progressions, that’s a good start. If they mention a lot about play, skill tasks, and movement. That’s good too.
- Ask a for a free trial or sample session if hiring a trainer or gym. If a trainer or coach doesn’t know your kid at all, they should do a preliminary assessment, and pick simple exercises that look relatively easy. Ask the purpose of the exercise, and if their answer is overly confusing, “scientific-sounding” or doesn’t even make sense to you, that’s not a good sign. They should be able to explain simply what they are doing, and why, what the benefit will be for the sport etc. Exercises should be a lot of bodyweight based, basic lifting movements that are pretty recognizable. Squats, pushups, pullups, cleans, medicine ball throws, swings etc and they should happily regress a movement that is obviously too difficult. First sessions or classes are not the time to be doing lots of speed work, fancy or uncomfortable movements, or heavily loaded stuff. Good form is easy to spot, especially in kids. Kids can’t really “cheat” movement too well. If it looks really yucky (even if you are unpracticed at watching) it probably is.
If a child falls behind or is obviously struggling, how does the coach respond? This is not to instill fear of trainers or coaches, but it’s your money and your kid. Ask! Training is hard work, but there is just no good reason for kids to be grinding through exercises, almost puking or looking significantly distressed. The “go hard or go home” mentality is not healthy or applicable. This is not to be confused with developing mental resilience, competition toughness, or learning to push boundaries appropriately. That usually comes with time though. The best coaches are ones who get to know a kid, are good teachers, part of their support system, and good examples of the qualities you would like to see developed in your child. Strength, positivity, compassion, work ethic etc. If you don’t get those impressions…..go somewhere else. The one who yells, screams for more weight, and wants to hype them up, is probably not your best bet. At the same time, remember that if you find a good coach, its a relationship. It will be their job to help them progress past discomfort, doubt etc in order to compete and excel.
A good coach will respect:
2.) Proper progression from the basics to sport-specific.
3.) Fun and participation
4.) What might be termed functional or natural movement patterns. Pushing, pulling, squatting, agility and a variety of movement skills, both foundational and sport-specific
5.) A supportive environment that allows kids to discover their skills and challenge themselves appropriately
What if you are completely ignorant about lifting, exercise etc and want the best for your kid’s physical and mental health long term?
1.) Make daily physical activity a priority in some form.
As an example my kids have: a bike, a pogo stick, a frisbee, a skateboard, a basketball. They climb trees, hills and play in parks. We play tag, wrestle on the ground, and go sledding. They walk up and back to school. They have participated in the following sports: wrestling, basketball, tae-kwon-do, obstacle racing, track and field, volleyball and ultimate frisbee. They have swung kettlebells and done pullups on gym rings. They carry shopping and walk everywhere. A wide base means just that: wide. Let them try out multiple sports and activities. Make them your own motivation to get moving and lifting. Get outside and play on a playground! Buy them stuff that requires play and exercise. A good bike and helmet rather than another video game. A class package to a parkour class. That stuff is exciting. Kids are susceptible to culture, environment, social pressure (the right kind), parental influence and conditioning (both mental and physical). You are building their future fitness NOW. It doesn’t need to be formal, it doesn’t need to be special or specific, it just needs to happen. Get them off their asses. Literally.
2.) Let them participate and engage in a wide variety of sports.
3.) Let them take classes
4.) Invest in some basic weight equipment and learn how to use it. Dumbbells and kettlebells are your best option.
Your best class options for a good mix of skill and strength are:
1.) Martial arts-based. Especially judo, wrestling, grappling etc
2.) Tumbling or gymnastics/parkour based
3.) Crossfit kids classes (please just remember the common-sense about picking coaches or classes and seek out someone properly certified)
4.) A properly certified USA Weightlifting (or other country’s federation) class
You can’t get out of putting some thought and research into this. Weight training isn’t rocket science, especially if you are not going to try and do something fancy and you have some common sense. If your kid plays a sport competitively, keep tabs on their practices, recovery, relaxation, and hire a skilled strength coach if that is an option.
In the next post, I will link away to resources for parents and coaches. If you are a coach, there is some really great stuff that was passed on to me.
1.) Hargrove, Todd. “Motor Development and Primal Patterns.” A Guide to Better Movement. 1st ed. Better Movement, 2014. Print.
2.) Gallahue, David, and Frances Cleveland-Donnelly. Developmental Physical Education for All Children. 4th ed. Human Kinetics, 2007. Print.
3.) ”Canada LongTerm Athlete Development.” Canadian Sport for Life (CS4L). Canadian Sports Centres, 1 Jan. 2010. Web. 13 Nov. 2014.
4.) Burgess, Ryan. “Flip the Pyramid and Save America.” You Are Being Http://www.jtsstrength.com/articles/2013/12/02/flip-pyramid-save-america/. 2 Dec. 2013. Web. 13 Nov. 2014.
5.) Zatsiorsky, Vladimir M. “Strength Training for Young Athletes.” Science and Practice of Strength Training. 2nd ed. Champaign, IL: Human Kinetics, 1995. Print.
6.) ”Review of Explosive Running by Anatoly Bondarchuk.” Elite FTS. Elite FTS, 13 Feb. 2008. Web. 13 Nov. 2014. <http://articles.elitefts.com/products-reviews/review-of-explosive-running-by-anatoly-bondarchuk/>.
7.) ”Youth: Early Sport Specialization – Athlete Strength and Performance.” Athlete Strength and Performance. ASP Athlete Strength and Performance, 7 Feb. 2014. Web. 13 Nov. 2014. <http://www.athletestrengthandperformance.com/youth-early-specialization/>.