Transcript ARCHERY WORLD CUP

World Archery Coaching
Seminar
London, GBR
8 - 11 November 2011
9 November 2011
The Biomechanics of Gold
Medal Shooting
Oliver Logan
English Institute of Sport
Biomechanist – ArcheryGB
EIS Skill Acquisition Lead
2011 World Archery Coaching Seminar
Note!
There are many different styles
and techniques of shooting.
What is presented here is only
our thoughts on what works well.
2011 World Archery Coaching Seminar
Discussion Areas
 The Biomechanics of Archery
 Automatic Technique
 Skill Acquisition
2011 World Archery Coaching Seminar
Posture
 Good posture is extremely important for:
 Balance
 String Clearance
 Effective posterior chain use
 Shooting mechanics
2011 World Archery Coaching Seminar
Posture
 An ideal posture would see the centre of gravity
of the archer centred between the feet
2011 World Archery Coaching Seminar
Good Posture
Forward Lean
Thoracic/Lumbar
Extension
2011 World Archery Coaching Seminar
2011 World Archery Coaching Seminar
2011 World Archery Coaching Seminar
2011 World Archery Coaching Seminar
2011 World Archery Coaching Seminar
Alignment
 Proper alignment is important for a robust
consistent competition technique
 Allows the forces of the bow to be controlled via
bones and joints rather than through the muscles
 Creates a more consistent repeatable technique
that stands up under pressure
2011 World Archery Coaching Seminar
Alignment –Coronal Plane
2011 World Archery Coaching Seminar
Alignment
 2 types of alignment used in world archery
2011 World Archery Coaching Seminar
Alignment
Energy Stored in
Limbs
2011 World Archery Coaching Seminar
Alignment
 This way primarily uses posterior deltoid muscle
to draw and upper trapezius to anchor
2011 World Archery Coaching Seminar
Alignment
Energy Stored in
Limbs
2011 World Archery Coaching Seminar
Alignment
 This way uses more of the scapular muscles such
as all of the Trapezius muscle, rhomboids as well
as posterior deltoid
2011 World Archery Coaching Seminar
Recurve Men Draw Weight in Lbs
54
52
50
48
46
44
42
40
2011 World Archery Coaching Seminar
Recurve Women Draw Weight in Lbs
50
45
40
35
30
25
20
15
10
5
0
2011 World Archery Coaching Seminar
Alignment - Sagittal
 Again very important that the archer stands up
straight and does not lean to the side. The archer
should be like a crane
2011 World Archery Coaching Seminar
2011 World Archery Coaching Seminar
Execution
 Consistent execution is the result of a good
physical setup, draw and alignment
 Execution is the difference between the best and
all the rest
 Some videos of different execution
2011 World Archery Coaching Seminar
Execution Errors
 As the signal from the brain to relax the fingers is
sent some of the upper body musculature also
relaxes – causing collapse or softness on the shot
 Can result from:
 Pain response
 Not learning the shot properly
 Poor alignment
 Lack of strength
2011 World Archery Coaching Seminar
Tracking Execution Errors
 Can quantify strength of execution via 2D
tracking.
 6 marker upper body model
 Able to provide joint angles, displancements,
velocities and accelerations
2011 World Archery Coaching Seminar
What execution looks like
Draw Wrist Horizontal Velocity
1.6
1.4
Velocity (m/sec)
1.2
1
0.8
0.6
0.4
0.2
0
-0.2
Time (sec)
-0.02
-0.03
-0.05
-0.06
-0.07
-0.09
-0.10
-0.11
-0.13
-0.14
-0.15
-0.17
-.2
-.4
Time (sec)
0.17
0.15
0.14
0.13
0.11
0.10
0.09
0.07
0.06
0.05
0.03
0.02
0.01
-0.01
Velocity (m/sec)
2011 World Archery Coaching Seminar
Poor Execution Draw Wrist Horizontal Velocity
1.2
1.
.8
.6
.4
.2
.
2011 World Archery Coaching Seminar
Automatic Technique
 In archery when shooting at a target the archer
has an external focus on:
 Aiming
 Wind conditions
 Time
 The archer is not focusing on his/her technique.
Therefore if it is not well learnt or automatic then
it is more likely to break down
2011 World Archery Coaching Seminar
Draw Wrist Execution as Function of Distance
1.4
1.2
1.
close blank boss
Axis Title
.8
50m blank
50m target
.6
60m blank
60m target
.4
70m blank
70m target
.2
.
-.2
2011 World Archery Coaching Seminar
Skill Acquisition
Increase Contextual
Interference
-Increase Draw Weight,
shoot at a target face,
increase shooting
distance, add pressure
etc.
1. Learning The Movement
-High frequency live feedback
(visual/coach)
-Archer has low self feedback
and awareness
2. Training The Movement
-High frequency delayed
feedback (visual/coach)
-Archer improves awareness and
self feedback
4. Challenging The Movement
-No external feedback
-Archer can self correct and
movement is autonomous
3. Practising The Movement
-Low Frequency Delayed
feedback (visual/coach)
-Archer has high movement
awareness and self feedback
2011 World Archery Coaching Seminar
References
Axford, A. (1995). Archery Anatomy (1st ed.). London UK: Souvenir Press.
Ertan, h., Kental, B., Tumer, S.T., and Korkusuz, F. (2003). Activation patterns in forearm muscles during archery shooting. Human
Movement Science, 22, 37-45
Ertan, H. (2009). Muscular activation patterns of the bow arm in recurve archery. Journal of Science and Medicine in Sport, 12, 357360.
Lin, Jiu-Jenq, Hung, Cheng-Ju, Yang, Ching-Ching, Chen, Hsing-Yu, Chou, Feng-Ching and Lu, Tung-Wu (2010). Activation and
tremor of the shoulder muscles to the demands of an archery task. Journal of Sports Sciences, 28: 4, 415-421.
Leroyer, P., Hoecke, V., and Helal, N. (1993). Biomechanical study of the final push-pull in archery. Journal of Sports Sciences, 11, 6369
Mann, D. L., and Littke, N. (1989). Shoulder injuries in archery. Canadian Journal of Sports Sciences, 14. 85-92.
Nishizono, H., Shibayama, H., Izuta, T., and Saito, K. (1987). Analysis of archery shooting techniques by means of electromyography.
International society of biomechanics in sports. Proceedings. Symposium V (pp. 365-371). Athens, Greece.
Park. J., and Larven. J. (2007) Archery Australia Shooting Technique: Biomechanics.
Schmid, M., Schieppati, M., and Pozzo, T. (2006). Effect of fatigue on the precision of a whole-body pointing task. Neuroscience, 139,
909-920.
Logan, O. (2011). A framework for technical modification: an archery case example. The Sport and Exercise Scientist: the official
publication of the British Association of Sport and Exercise Sciences. (29).
Masters, R.S.W. and Maxwell, J.P. (2004). 'Implicit motor learning, reinvestment and movement disruption: What you don't know won't
hurt you?'. In Williams, A.M. and Hodges, N.J. (eds) Skill Acquisition in Sport: Research, Theory and Practice. Routledge: London
Masters, R.S.W. (2008). 'Skill learning the implicit way - say no more!'. In Farrow, D., Baker, J. and MacMahon C. ‘Developing Sport
Expertise: Researchers and Coaches Put Theory Into Practice.’ Routledge: London
Porter, J.M and Magill, R.A. (2010). 'Systematically increasing contextual interference is beneficial for learning sports skills'. Journal
of Sports Sciences, (28): 1277-1285.
Schmid, M., Schieppati, M., and Pozzo, T. (2006). Effect of fatigue on the precision of a whole-body pointing task. Neuroscience, 139,
909-920.
Thank you…
Ready to answer your questions!