Children in the weights room

1. Children in the weights room The facts and fallacies: What the research says and how we can help with long term athletic development.

2. Who AM I? • PG Cert S&C St. Mary’s Twickenham • BSc (Hons) Sports Science • ASCA Level 1 Strength & Conditioning Coach • USAW Level 1 Sports Performance Coach • NSPA Certified Weightlifting Performance Coach • NSPA Certified Program Design Specialist • Current Head S&C coach for Hong Kong lacrosse men’s program • Head S&C coach for Hong Kong U20 Rugby at 2015 World Trophy • Ex-GB international athlete at 2 Senior World Championships • International Coach at 6 Junior World Championships (Team GB and Team Hong Kong) • S&C coaching experience with Premier League football team • S&C coaching experience with professional rugby team

3. Why this topic? • Personal experience with parents, teachers, head coaches. • Experience at international competitions and seeing athletes from other countries. • Personal interest in the development of youth athletes.

4. Common fears • It will stunt my child’s growth and natural development • It’s not safe, their bones are still soft • Children are too young to begin strength training and should only concentrate on bodyweight exercises • They will get injured or hurt • They already do enough sport, they don’t need strength training

5. Stunting growth • New York Times article on Japanese child labourers (1970’s). • Japanese child labourers were carrying heavy objects and were short. • Concluded that carrying heavy objects made them short. • This idea transferred over to the weightlifting

6. Growth is predetermined by DNA & controlled by hormones • Oestrogen slows growth during puberty. • Lack of sleep and additional stress can suppress the production of growth hormone. Chagin et al. (2014) Bone size approx. 10% larger between playing and non-playing arms of young prepubertal tennis players. Kannuset al. (1995)

7. But powerlifters are short…. • Weight class strength sport – Bench Press, Squat, Deadlift. • Squat – hips below knees • Bench Press – bar to chest and straight locked arms • Deadlift – bar to upright standing position • Being shorter is generally an advantage as the bar needs to travel less distance. Work = Force x Distance so the same force (to lift a 200kg barbell) over less distance, requires less work. • The best powerlifters are usually short due to their shorter levers and having to move the bar through a lower ROM.

8. If lifting weights makes you short…. Does playing basketball make you tall?

9. Stunting growth concern summary • There has been no scientific study done that has proven that weightlifting in children can stunt their growth. • Scientific research actually indicates that childhood is the opportune time to build bone mass and enhance bone structure by participating in weight-bearing activities. • Strength training is beneficial to bone formation, density and growth. • This perception came from an observational comment made about undernourished Japanese child labourers in the 1970s.

10. Bones are still soft • Lots of research shows that resistance training actually increases bone mineral density, bone mineral content and bone area in children.

11. Exercise in PRE-Pubescent children - Bone Mineral Density/Content, Bone Mass. (Tanner stage 2&3)

12. Exercise in Pubescent children - Bone Mineral Density/Content, Bone Mass. (Tanner stage 4&5)

13. Research shows that endurance training can have a negative effect on bone density, though the cause of this is not fully understood; It is thought that it could be due to calcium loss through perspiration. • Ground reaction forces in running can be as much as 4 times bodyweight. (Nilsson & Thorstensson, 1989) compared to 1.4-1.5 times bodyweight in olympic lifting (Lauder & Lake, 2008). • This equates to over 150 tonnes of pressure for a 50kg runner over 1 mile.

14. Soft bones concern summary • Resistance training proven to increase bone density and mineral content in children as young as 4 years old. • Safer on bones than some traditional methods of exercise in terms of ground reaction forces and for bone composition. • Weightlifting in older youths is not as effective in increasing bone density or mineral content as it is in younger children. • Can be attributed to diet.

15. Injury concerns Injuries can happen in any sport or recreational activity. Every sport carries a risk. Injuries in weightlifting – 0.84 to 4.4 injuries per 1000 hours of participation. (Brown & Kimball, 1983; Keogh et al. 2006; Raske & Norlin, 2002; Calhoon & Fry, 1999). Injuries in running - 2.5 to 12.1 injuries per 1,000 hours. (Van Mechelen, 1992).

16. NCAA and National Athletic Trainers Association research in 2007 showed the following injury rates for sports.

17. A well-designed strength training program appropriate for the young athlete’s age and body habitus should not excessively stress growth plates. • Sports such as gymnastics and baseball, which involve repetitive impact and torque, provide a greater risk of epiphyseal injury. • The rare case reports of epiphyseal plate fractures related to strength training are attributed to misusing equipment, lifting inappropriate amounts of weight, using improper technique, or training without qualified adult supervision. Oliver et al. (2011)

18. Strength training can help prevent injuries • Preventive exercise (prehabilitation) focuses on the strength training of muscle groups that are subjected to overuse in specific sports. (Dominguez, 1978). • Similarly, strengthening the hamstrings, glutesand quadriceps can reduce lower extremity injuries in male and female youth athletes. (Hejna et al., 1982; Hewett et al., 2006). • A simple strength training program alone may decrease an athlete’s risk of injury. (Lephart et al., 2005)

19. Physical inactivity is recognised as the fourth leading risk factor for global mortality for non-communicable diseases, and participation in a variety of physical activities, including those that strengthen muscle and bone, is encouraged. - World Health Organisation • In the past, it is has been common to prescribe aerobic exercise (such as jogging) to overweight and obese youth. • When weightlifting in a properly supervised and safe environment, youths utilise a variety of multi-muscle, multi-joint exercises, which can produce positive alterations in body fat levels, cardiorespiratory variables and various motor fitness parameters.

20. Injury concern summary • This type of training poses no danger to students if it is safely administered by a qualified professional, and can actually lead to a significant reduction in injury risk. • The associated increases in bone density, muscular strength, movement skill competency and self-confidence that are attached to paediatric S&C make it an invaluable pathway for injury prevention in children and adolescents. • Injury rates are actually a lot lower relatively compared to many sports offered at schools.

21. Too young to begin strength training • Studies have demonstrated that children can improve strength by 30% to 50% after just 8 to 12 weeks of a strength-training program. (Faigenbaum et al., 2002; Faigenbaum et al., 2003; Falk & Mor, 1996; Sewall & Micheli, 1986; Weltman et al., 1987). • Twice-weekly strength training in boys and girls between the ages of 7 and 12 years produced significant strength gains in the chest press. Faigenbaumet al. (2002) • Expected strength gains of 30%-40% are typically observed in young people following participation of an S&C programme. United Kingdom Strength and Conditioning Association

22. Some studies have demonstrated sport-specific improvement after strength training. (Gorostiaga et al., 1999; Ramsay et al., 1990) • Swim times and event-specific gymnastic performance have improved following a resistance training program (Blanksby & Gregor, 1981; Query & Laubach, 1992) • However, a study also showed that the gains in strength do not always produce linear improvements in sports performance • (Christou et al., 2006)

23. Childhood development is highly individualised - youths of the same chronological age will significantly differ in biological status. This discrepancy can often equate to 4 to 5 years in age difference. • Due to the advantages of being an ‘early maturer’, the boy on the right is likely to receive much more attention and coaching, despite having the same long term potential as the boy on the left. • Maturity offset can identify when the training of each fitness component should be emphasised.

24. Peak Height velocity - phv • Period of time where a child experiences fastest upward growth in stature (usually 2 years earlier in girls than in boys). • Can lead to a breakdown in technique due to lack of control of longer levers – Skill based training might need to be reduced in favour of more strength based training. • This period is an opportunity for the athlete to make greater improvements in athleticism (structural improvements generally made better during this time – hypertrophy & strength).

25. How is phv calculated? • Players are measured (height, weight, seated height). • Spreadsheet will calculate estimated age at PHV. • A number (in years) will be given for each athlete to determine how far they are away from PHV. • A negative number given (how far from PHV is athlete) means that athlete has already passed PHV. A positive number means that athlete is yet to reach PHV.

26. Peak Height velocity - phv

27. How does phv affect training? • Before PHV reached – Learn to Train. • Developing strength with bodyweight/medicine ball/plastic piping exercises (low resistance, high volume). • Once PHV reached – Train to Train. • Learning correct weightlifting techniques (increase resistance, reduce volume).

28. ‘Too young’ concern summary • Strength is gained through development of the CNS which can then lead to greater gains in hypertrophy as they get older. • It is appropriate to develop movement mechanics and exercise technique during the early years, which can subsequently be exposed to greater external loads during adolescence and the onset of peak height velocity. • The improvement in motor coordination, movement, bone density, strength, and body composition at a young age will only help later in life. • PHV can be used to determine suitable time to start training.

29. Already active – no need • Vertical jump height (Hori et al. 2008; Channell & Barfield, 2008; Loturco et al. 2015; plus a further 9 studies not listed here). • Vertical jump power output (Carlock et al. 2004; Hori et al. 2008: Nuzzo et al. 2008) • Vertical jump peak velocity (Nuzzo et al. 2008) • Jump squat height • (Häkkinen et al. 1986) • Jump squat power output • (Baker & Nance, 1999) • Sprint running speed over short distances • (Hori et al. 2008; Loturco et al. 2015) • Change of direction (COD) ability • (Hori et al. 2008) Olympic lifts or weightlifting derivatives are associated with:

30. We need to encourage our young athletes to strength train.  • Physically prepared for training –Youth athletes are still growing and often lack coordination. • Prevent Overuse injuries – Youth athletes have inherent musculoskeletal imbalances and lack both strength and endurance. • Decrease risk of traumatic injuries - Just because these injuries cannot be predicted, doesn’t mean they can’t be prevented. 

31. Improve athletic performance - By working with professionals, youth will work toward optimisingtheir mobility, stability, coordination, strength, and movement efficiency. • Improve self confidence and self esteem - Teach youth athletes how to train properly and give them the confidence to do so. Show them what they can accomplish. They see what their body can do that it couldn’t do before. • It’s FUN! - Mixing up training and adding in resistance exercises is and should always be fun. This way youth don’t feel like they are always practicing and playing their sport, but they know they are still working toward improving their skills. 

32. The current model in youth sports looks one of two ways Either: • Youth are training for their sport with their coaches, but either don’t follow a resistance program or they follow a program made as well as could be made by a parent or from an online source. Or • Youth do some resistance/strength training but the time per lesson is limited, and though importance is placed on form, when this athlete is training with their peers in the weight room, guess who is loading up the bar?

33. A meta-analysis of the effects of olympic weightlifting • Olympic weightlifting is superior to traditional resistance training by 5.1%. Hackett et al. (2015). • Olympic weightlifting improved 10m sprint time to a greater extent than vertical jumping. Tricoliet al. (2005). • Olympic weightlifting programs can increase aerobic capacity. Stone et al. (1983).

34. ‘already active – no need’ concern summary • There is more reason for youth athletes who are more active to be doing strength training to help with injury prevention. • Expecting children to be able to run, jump, change direction and stop effectively without giving them the foundation of strength is dangerous and irresponsible. • Strength training such as performingsquats and single leg squats introduce the athlete to the function of sequenced flexion/extension of the ankle, knee and hip joints, in essence a pre­requisite to movement.

35. School sports should be used for fun or to prepare athletes for professional or high level sports, not to win championships through inappropriate training. A lack of basic physical training coupled with an extensive competition schedule has limited their future sporting performance by reducing, not improving, their athletic and functional capabilities. • If athletes are destroyed in their childhood/teenage years, it’s very difficult to get them back to being a good athlete. • Sports educators, whether in the classroom or the weights room, should be looking to produce athletes with good athletic and functional qualities without pronounced physical limitations. Look at the big picture so we know how fundamentally important the right start is. “We worry about what achild will be tomorrow, yet we forget that he or she is someone today.” (Stacia Tauscher)

36. Food for thought

37. How I run my program – (Regardless of Age) • All student athletes must complete the 12-week injury prevention program including correct breathing and activation techniques. • All student athletes go through a 5 level introduction phase, initially of bodyweight training then progressing on to soft resistance training. • Once they have completed level 5 of the introduction phase, they can request to take the physical competency test at any time (tests are every fortnight). • ONLY once they meet the criteria of the minimum 18 points required, will they be allowed to use the barbells and move onto the 5 level strength phase.

38. Physical competency testing • Students must achieve a minimum score of 18 to pass the test. • If athletes fail the test, they must wait 2 weeks to re-take it. • Girls test is slightly lower for upper body but same for the rest.

39. How I run my program cont’d • Focus on long term athletic development. I want to produce students who go on to do great things, not ones who are champions at 15 and then burn out. • No time limit on the phases, progression wont be at the same rate for all athletes so fixed blocks of 4-6 weeks doesn’t always work. • Technique! Technique! Technique! • Activation before movement. • Movement before strength. • Strength before power.

40. conclusion • Strength training, when performed in a controlled, supervised environment, can help children and adolescents of all athletic abilities safely improve their strength and overall health and well-being. • The health benefits of strength training far outweigh the potential risks, especially in today’s society where childhood obesity continues to rise. • Teaching progressions from bodyweight to soft resistance then testing for physical competency is a better method than just ignoring strength training for youth athletes all together. • Preparation NOT annihilation!

41. Short ­term success has ruined promising careers of young athletes. Having athletic talent does not necessarily mean having to deliver the performance NOW. It is much safer to consider talent as the ability to produce great performances LATER.

42. References

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