biological maturation of youth: assessment and implications · pdf filebiological maturation...
Post on 05-Mar-2018
222 Views
Preview:
TRANSCRIPT
Biological Maturation in Young Athletes
Dr. Sean P. Cumming
Department for Health
(s.cumming@bath.ac.uk)
Biological Maturation of Youth:
Assessment and Implications
Biological Maturation in Young Athletes
Why study growth & maturation in sport?
1. Children grouped by age for training & competition; yet vary greatly in size & maturity
2. This has implications for (1) talent identification (2) training design (3) competition
Biological Maturation in Young Athletes
Maturation: A definition
• Progress towards the adult state; occurs in multiple bio-systems (dental, hormonal, skeletal sexual)
• Defined in terms of (1) status (2) tempo & (3) timing (i.e., early, on-time, late)
Biological Maturation in Young Athletes
The timing of maturation
• Children experience maturational events (e.g., puberty, menarche) at different ages (early, on-time, late)
• Genetically driven yet susceptible to socio-environmental factors; impacts physical, psychological & athletic development
Biological Maturation in Young Athletes
Early maturing males
• Physically larger from 8 years; enters puberty 10-11 years
• Greater pubertal gains in height, weight, BMI, absolute/relative muscle mass
• Positive/adaptive psychological profile
Biological Maturation in Young Athletes
Late maturing males
• Enter puberty 13-14 years
• Smaller pubertal gains in height, weight, BMI, absolute/relative muscle mass; taller/more linear as adults
• Anxious, socially awkward, submissive and immature in behaviour
Biological Maturation in Young Athletes
Pubertal timing & functional capacity in males
Vertical jump
cm
55
50
45
40
35
30
12 13 14 15 16 17 18
Shuttle run20
21
22
23
24
s
Flexed arm hang
15
20
25
30
35
40
s
Sit and reach
18
20
22
24
26
28
cm
Plate tapping (20 sec)
12 13 14 15 16 17 18 12 13 14 15 16 17 18
90
80
70
100
n
Arm pull
20
30
40
50
60
70
80
kg
Biological Maturation in Young Athletes
How does timing impact sport involvement?
1. Talent identification and athlete section
2. The design of training and conditioning programmes and the potential for injury
3. Grouping of athletes for competition
Biological Maturation in Young Athletes
1. Talent identification and athlete selection
• Talent is defined by athletic aptitude and success within the athletes age groups
• Aptitude and success can, however, be masked or enhanced by differences in maturational timing
Biological Maturation in Young Athletes
Maturation & evaluation
• Early maturity advantageous for…
• Explosive power (CMJ, VSJ, SLJ)
• Anaerobic power
• Isometric strength
• Sprinting (30m)
• Agility (shuttle run, sprint with slalom)
• Endurance
Meylan et al., et al., (2010)
Biological Maturation in Young Athletes
THE CONTRIBUTION OF MATURITY & GROWTH CHARACTERISTICS TO
PERFORMANCE IN ELITE PORTUGUSESE PLAYERS
11
41%59%
Vertical Jump Performance
Maturity and growth characteristics
Unexplained variance
50%50%
30m sprint time
Maturity and growthcharacteristics
Unexplained variance
21%79%
Aerobic Performance
Maturity and growthcharacteristics
Unexplained variance
13%
87%
Ball Control With Body
Maturity and growthcharacteristics
Unexplained variance
8%
92%
Shooting Accuracy
Maturity and growthcharacteristics
Unexplained variance
Malina et al., (2004, 2005)
Biological Maturation in Young Athletes
12
* Buchheit & Mendez-Villanueva (2014) J Sports Sci, DOI 10.1080/02640414.2014.884721
Biological Maturation in Young Athletes
Maturation and athlete selection
• Selection bias for males who are on-
time or advanced in maturation in
most sports; increases with age and
competitive level
• Bias in female varies relative to the
demand of the sport; Tennis (Early);
Aesthetic and endurance sports
(Late)
Biological Maturation in Young Athletes
Questions of concern
1. Are selection strategies favoring players on attributes not
fully realized until after puberty counterproductive?
2. Are early maturing boys encouraged to play to their
strengths at the neglecting their technical development?
3. Are talented yet late maturing and/or smaller boys being
overlooked or excluded too early?
Biological Maturation in Young Athletes
Too small for football?
Biological Maturation in Young Athletes
Biological Maturation in Young Athletes
Biological Maturation in Young Athletes
"I was small for my age. I was a late
developer. ......it’s hard to call a
player at such a young age. After that
I went to Spurs when I was 11.
"It wasn't like it took off straight from
then, I still had to work hard. There
were highs and lows along the way.
As I got older and older, I grew up a
bit, caught up to the rest of the
players my age and it went from
there, really”.
Harry Kane – Tottenham Hotspur &
England International
Biological Maturation in Young Athletes
Upper body strength
Lefevre et al., (1990) Annals Hum. Biol., 17, 423-34
Biological Maturation in Young Athletes
Lower body strength
Lefevre et al., (1990) Annals Hum. Biol., 17, 423-34
Biological Maturation in Young Athletes
Power
Lefevre et al., (1990) Annals Hum. Biol., 17, 423-34
Biological Maturation in Young Athletes
Speed
Lefevre et al., (1990) Annals Hum. Biol., 17, 423-34
Biological Maturation in Young Athletes
Upper body endurance
Lefevre et al., (1990) Annals Hum. Biol., 17, 423-34
Biological Maturation in Young Athletes
Bio-banding: A renaissance
• Process of matching players on growth and/or maturity attributes rather than age
• Applicable in the contexts of (1) talent identification, (2) development, and (3) competition
Biological Maturation in Young Athletes
1. Bio-banding and talent identification
• EPL academies evaluate players relative to age and maturity status
• Helps practitioners better identify players strength, weaknesses, and future potential
-2
-1
0
1
205m Sprint
10m sprint
20m sprint
30m sprint
505 Agility Left foot
505 Agility RightFoot
CMJ
Yo-Yo
Player AFitness Z Scores for U12s
-2
-1
0
1
205m Sprint
10m sprint
20m sprint
30m sprint
505 Agility Left foot
505 Agility RightFoot
CMJ
Yo-Yo
Player A:Fitness Z Scores for 95% PAH
Biological Maturation in Young Athletes
26
* Votteler & Honer (2014) Eur J Sports Sci, 14, 433-42
Developmental trajectories for performance
Biological Maturation in Young Athletes
Growth potential: A Case Example
Biological Maturation in Young Athletes
2. Bio-banding and training
• All fitness attributes responsive to training at all ages; yet adaptationsvary with maturity *
• To optimize training effects/enhance safety, match the athlete’s program to his/her maturational status and skill set
* Lloyd & Oliver (2012) Str Cond J, 34, 61-72; ** Blanchard (2015)
http://blogs.bmj.com/bjsm/2015
Biological Maturation in Young Athletes
Physical Youth Development (Lloyd & Oliver, 2012)
Biological Maturation in Young Athletes
Bio-banded training groups
* DePledge (2015) Application of growth and maturation at Southampton FC
Biological Maturation in Young Athletes
* Blanchard (2015) BJSM Blog online
Biological Maturation in Young Athletes
The clumsy child phase
• Growth spurt requires adjustment to rapid changes in limb length, fitness & mechanics *
• Controlled movement, reactions/co-ordination, running & landing mechanics, sport specific skills for youth circa PHV *
* Blanchard (2015)
http://blogs.bmj.com/bjsm/2015/04/14/supporting-young-athletes-
to-stay-and-excel-in-sport-whats-the-role-of-the-medical-team-
and-what-does-expanding-our-view-of-maturation-have-to-do-
with-it/
Biological Maturation in Young Athletes
Maturation and overuse injuries
• Growth spurt a risk factor for overuse injuries, especially epiphyseal (Osgood-Schlatter’s, Sever’s disease) *
• Training load and athlete’s health needs to be be closely monitored during the growth spurt to avoid overuse injuries
* Blanchard (2015) http://blogs.bmj.com/bjsm/2015
Biological Maturation in Young Athletes
* Price et al., (2004) Brit J Sports Med, 38, 466-471
Biological Maturation in Young Athletes
3. Bio-banding and competition
• Bio-banding can be used to match athletes by maturation rather than age for competition
• Games can be grouped in biological bands or players can play up or down an age group
Biological Maturation in Young Athletes
Rhodri Oliver
88%
Marty Stanner
92%
Tom Curran
89%
Brian Corsie
78%
Keith Moar
87%
Ian Ramsden
92%
Mark Atkinson
85%
Magnus Tapp
88%
Geoff Hay
96%Grant C’david
85%
Mike Slavin
87%Tom Dompier
86%
Baxter Jones
89%
Joe Icemann
86%
U-13s
M PAH = 86.5%
Biological Maturation in Young Athletes
Bio-banding in football
• Premier League hosted world’s first bio-banded competition in football (Southampton, Norwich, Stoke, Reading)
• Players aged between 11 to 14 years between 85-90% predicted adult height
http://www.premierleague.com/en-gb/news/news/2015-
16/sep/170915-premier-league-bio-banding-helping-late-
developers.html
Biological Maturation in Young Athletes
Bio-banding in Football (cont.)
• Coaches & players rated experience as overwhelmingly positive
• "In this type of match they don't go into a game worried about other players being too big, too quick and too physical for them to compete with, but know that the challenge will be something that is manageable. This will also assist us with talent identification, retaining late developing players for longer periods."
Biological Maturation in Young Athletes
Testing a bio-banded competition in EPL (cont.)
• Early maturers (playing up) reported working harder, relied on technical over physical attributes, adapted to faster game, relied more on teammates
• Late maturers (playing down) reported greater composure, more opportunity to demonstrate technical skills, leadership opportunities
Biological Maturation in Young Athletes
Early maturers playing up
“it’s definitely made me move the ball quicker than I would and I don’t use my strength as an advantage as much as I do with my own age group” (EM1, P4)
“You learn a lot more playing like this than you would normally playing with your age group” (EM2, P4)
“It made me more confident, playing with older boys, and getting used to the pace. Made me quicker on the ball. ” (EM1, P3)
Biological Maturation in Young Athletes
Late maturers playing down
“in a normal game you might only be able to do a bit of magic twice, but in here, every time you get the ball there is a chance that you can do it” ( LM1, P3)
“You're also more composed on the ball...there's not a massive 6' 5" player running up ...you know that it's somebody your size, you can push off as well as keep the ball” (LM1, P4)
“ I feel like it's given us more chance to stay at the club... Finally, people have been realising that small players are good for the academies” (LM1, P1)
Biological Maturation in Young Athletes
Bio-banding: The future
• Examine ‘in game’ differences between early & late maturing males (GPS, match analysis)
• Competitions different maturity bands (e.g., 90-95%, 95-100%)
• Interest from other sports (cricket, rugby, gymnastics, triathlon)
Biological Maturation in Young Athletes
Take home messages
• When working with young athletes, it is important to consider individual differences in growth and maturation
• Selection strategies that favour athletes on attributes that are not fully realised until adulthood may be counterproductive
• Bio-banding has the potential to account for individual differences in maturation; optimise player development and safety
Biological Maturation in Young Athletes
Thank You
Any Questions?
top related