Coaching Pedagogy - How to Execute a Knuckleball Free Kick
This blog
will seek to demonstrate an overall understanding of pedagogical strategies
that are used within sport whilst establishing the pre-requisites of technical
instruction and the effect this has on the learning environment. As well as
this, there is a need to plan, conduct and review sessions that will provide an
intervention to a learnt technique.
A direct
free kick is defined by (Robinson, 2014) as a:
"Resumption from
the spot of an infraction with a pass or a shot at goal; any members of the
opposing team must be at least 10 yards away when the ball is struck."
(Robinson,
2014)
Witzig(2006) believes that to perform a
'knuckleball' effect on a football, the ball must be struck with little or no
rotation at full force. The ball is then likely to veer from its original
course citing reasons such as wind currents and gravitational effects.
Key terms
Open environment :
"Performance is
adaptable, spontaneous and varied such as a football match in open play."
(Smith, 2013)
Closed environment :
"Performed in a fixed
environment where the equipment is fixed and conditions remain the same such as
a pole vault leap."
(Beashel et al, 2001)
Free kicks were often neglected within
football during previous seasons with teams often believing they hold little
value to the final result, however with the recent influx in higher quality
players and managers the philosophies on free kicks and the value they hold
within a game is changing, (Beard, 2015) decrees that more teams now are
accessing free-kick specialists in order to take advantage of these situations.
As referring to figure 1 below, free kicks are becoming more prevalent within
recent seasons adding to that the FK conversion rate significantly higher year
upon year.
Open environment :
"Performance is adaptable, spontaneous and varied such as a football match in open play."
Closed environment :
Free kicks were often neglected within
football during previous seasons with teams often believing they hold little
value to the final result, however with the recent influx in higher quality
players and managers the philosophies on free kicks and the value they hold
within a game is changing, (Beard, 2015) decrees that more teams now are
accessing free-kick specialists in order to take advantage of these situations.
As referring to figure 1 below, free kicks are becoming more prevalent within
recent seasons adding to that the FK conversion rate significantly higher year
upon year.
Free Kick Goals in the Premier League
Season
|
FK
Goals |
FK
Conversion % |
FK on
Target % |
Outside
Box Goals |
Outside Box
Conversion % |
Outside
Box SOT% |
|---|---|---|---|---|---|---|
| 2009/2010 | 32 | 4.86% | 27.51% | 139 | 2.85% | 24.43% |
| 2010/2011 | 29 | 4.48% | 25.77% | 137 | 2.84% | 24.80% |
| 2011/2012 | 29 | 5.24% | 25.68% | 177 | 3.67% | 24.93% |
| 2012/2013 | 32 | 5.57% | 28.40% | 163 | 3.55% | 24.54% |
| 2013/2014 | 28 | 9.46% | 30.41% | 114 | 4.17% | 26.33% |
Figure 1: Free kicks taken in the premier league between years 2009-2014
(Coverdale, 2014)
When improving upon performance, McCarron
proposes the performer must study the best practice of an elite performer as
this will showcase habits the player uses on a consistent basis.
About the Performer
The performer is
a male football player aged 19, looking to improve on a particular free kick
type known as a 'knuckleball' technique. The performer feels they are adequate
at the known skill but would like to improve to a higher level through coached
intervention.
Area for Improvement
In order for any improvements to be made
it is imperative to assess and profile the performance of an athlete to
mutually agree the areas to be intervened through coaching. This would occur
within a consultation setting with an observation of performance to confer with
the beforementioned areas for improvement.
 |
Figure 2: Performance Profile for Athlete Showing Skill Traits in Football
|
As figure 2 suggests, free kicks were agreed to be an area for the athlete to improve on within the performances which were viewed using both video and observational analysis to gain results for the above traits. McGinnis, believes that to improve skills, teachers/coaches may use their knowledge of mechanics to correct actions of a student or athlete in order to improve the execution of a skill.
Value of the skill
When deciding upon using an intervention to change the behaviour of the skill in question it is also important to raise the importance for this issue to be changed. When discussing the below graph, figure 3 shows that shots from outside the penalty area; from open and closed environments(normal shots and free kicks) are closely grouped with an average of 23.6 metres and 24.5 metres respectively.
 |
| Figure 3: Shots Taken From Outside the Penalty Area and Distance From Goal in the Barclays Premier League Season 2010/11 |
(Graham,2011)
 |
| Figure 4: Shots Converted in to Goals From Outside the Penalty Area in the Barclays Premier League Season 2010/11 |
(Graham, 2011)
Figure
4 suggests that direct free kicks from outside the penalty area are 1.9% more
likely to be converted than normal shots that are attempted from the same area.
This shows that within the season 2010/2011 it was more beneficial to win a
free kick around the area than to strike the ball from open play.
Best Practice
In the above, video 1 shows Gareth Bale performing a 'knuckleball' free kick attempt at goal. In order for the athlete to be assessed it is necessary to gain best practice evidence from an elite athlete, Bosch et al explains that you must understand exactly what should happen in good practice as without this it is impossible to measure the extent of existing gaps between the desired level and actual performance levels.
Athlete Practice
Video 2 - Shows Pre-Intervention Performance of Athlete
In the above, video 2 shows the athlete performing the 'Knuckleball' free kick attempt at goal. In order for the athlete to see improvement, video analysis must be acquired before the intervention is implemented to the athlete. In research conducted by social science network it was concluded that 65% of people are visual learners so this suggests around 2/3's of athletes will be able to visualise the area they need to improve whilst also considering that of best practice and making relevant comparisons to change behaviour.
Best practice vs Client - Stance
 |
| Figure 5: Elite Perfomer Stance when Performing 'Knuckleball' Free-Kick |
In
order to efficiently execute best practice, Shergold recommends its important to have an upright stance and to plant
the standing foot firmly for balance when striking the ball. As you can see in
Figure 5(above) Gareth Bale maintains an upright back whilst firmly planting
his foot when performing this action which consequently provides a good
technique in which to strike the ball from.
 |
Figure 6: Athlete Stance when Performing 'Knuckleball' Free-Kick |
Figure
6(above) shows how the athlete performs the same movement however demonstrates
bad technique which in turn promotes a bad angle and alleviates the power from
the strike. When comparing this to figure 5 it is clear to see the selected
area for improvement needs a successful intervention to enable best practice to
be performed.
 |
| Figure 7: Elite Perfomer Strike when Performing 'Knuckleball' Free-Kick |
Figure 7(above) shows how the ball
should be struck correctly when performing best practice. As you can also see
from figure 7 there is a high linear relationship between both of the elite
athletes legs, Anderson and Sideway propose that:
"The linear velocity of the kicking foot is highly correlated with
the resultant ball velocity"
(Anderson and Sideway, 2013)
Using this style of striking the ball it
allows any athlete to develop more power which in turn can make the ball
deviate in the air. The AIOP(American Institute of Physics) describe the
'Knuckleball' as a shot being hit at very low spin, and a lot of power which in
turn creates a zigzag trajectory.
 |
Figure 8: Athlete Stance when Performing 'Knuckleball' Free-Kick |
Figure
8(above) demonstrates how differently the athlete positions their body compared
to that of the elite performer. You can see how the athletes legs are not
lateral which reduces the amount of power they are able to create on the ball
to allow it to deviate in the air. An area for similarity however is how both
performers have positioned their arms, this allows for greater balance in which
to create the elevation on the ball.
Best practice vs Client - Follow through
 |
Figure 9: Elite Perfomer Follow Through when Performing 'Knuckleball' Freekick
|
When analysing figure 9 of the elite
performer it is clear to see the amount of contact time with the ball is much
greater than that of the athlete. Barfield(1998) suggests that a longer contact
time with the ball will maximise the transfer of the ball which in turn
increases speed as the ball heads towards the goal.
 |
Figure 10: Athlete Follow Through when Performing 'Knuckleball' Freekick |
When
comparing figure 10 to that of figure 9 the techniques of the players are very
similar. Both players use a motion which allows their body to transfer power
through the ball to enable the ball to reach high speed which in turn changes
the trajectory and movement of the ball. The main difference between figure 9
and 10 is the extension of the performers leg, the elite performer extends
their leg a lot further than the athlete which generates more power,
Inverso(2003) suggests it is important to follow through the ball with your
whole body as this generates more power transferred in to the ball.
Best practice vs Client - Elevation of shot
 |
| Figure 11: Elite Perfomer's Elevation of Shot |
Madoshi(2012)
believes that height is an important element when performing a knuckleball
shot, this is due to the topspin placed on the ball to allow the ball to drop
at a quick rate making the shot increasingly hard for the keeper to save. As
you can see in figure 11(above) the ball is above the crossbar at around half
the distance between the elite performer and the goal, this will then dip at a
ferocious rate to enhance the chance of a goal.
 |
| Figure 12: Athlete's Elevation of Shot |
Again, when looking at figure
12(above), the athlete has managed to elevate the ball in advance of the
crossbar however the shot lacks pace which doesn’t allow the ball to dip as
much as the figure 11. The stance of the athlete could also be improved as the
follow through is almost 'side on' by this point which further enhances the
belief which suggests there isn’t enough power to inflict the deviation on the
strike.
Best practice vs Client - Ball movement
 |
| Figure 13: Elite Performers Strike with Ball Movement |
In
studies undertaken on the movement effect that occurs during a knuckleball shot
it is concurred that the football is vastly effected by variations in wind and
aerodynamics that allows the ball to be so unpredictable (Asai et al, 2008).
When comparing figure 13 to the previous of figure 11 by the performer it is clear
to see the amount of deviation the ball has taken in such a small amount of
time, again signalling the difficulties the goalkeeper faces in these
situations.
 |
| Figure 14: Athletes Strike with Ball Movement |
When
looking at the athlete’s ball movement compared to that of the elite performer
it is clear to see the movement is only vertically this makes the ball easier
to save for the goalkeeper. Figure 14 shows the football at the bottom of the
goal however the football is very central allowing the goalkeeper a much better
chance of saving the shot.
Intervention
by Coach
Coaching
interventions are also known as the coaching process, this is defined by
Lyle(2005) as the:
"Instruction of motor skills"
(Lyle, 2005)
This shows that in order for their to be a
change in behaviour the coach must provide an instruction of motor skills which
will adapt the technique that has already been learnt in order for the skill to
be successful. When performing a knuckleball free kick this is known as a '
closed skill', this is performed under standard repeatable conditions(Mclester
and Pierre, 2007) which makes this skill much easier to provide an intervention
too as there is less aspects that could be varied.
Demonstration by Coach
Magill(1989)
describes the skill of demonstration as skilfully portraying the use of
features critical to a skill that is being learnt. Mawer(1990) furthered the
research of Magill(1989) by explaining not only that of demonstrating the skill
is important, the coach must display a level of verbal communication which aids
the athlete when learning the skill.
Demonstration - Stance
 |
| Figure 15: Coach Demonstrating Stance |
The coach must relay the demonstrations to the best of their ability in order for the athlete to be able to recreate this in the correct capacity. When comparing figure 15 to that of figure 5 it is clear to see the necessity on keeping the back straight when performing this technique.
Demonstration - Strike
Demonstration - Strike
 |
| Figure 16: Coach Demonstrating Strike |
In
figure 16, the coach is about to strike the ball; the coaches back is upright
and his left foot is firmly planted allowing the swinging action to be
performed by the right leg in order to create the power needed.
Demonstration - Follow through
 |
| Figure 17: Coach Demonstrating Follow Through |
In figure 17, the coach provides an
excellent demonstration showing the left leg still firmly planted after the strike.
Figure 17 also shows the coach using his arm and body shape in to order to send
the football in the correct direction whilst showing a great amount of follow
through with the striking leg.
Sessions Devised by Coach
In order to provide the intervention to the athlete the training would be complete under blocked practice, Simon and Bjork(2001) suggests using block practice, you are more likely to receive higher levels of future task performance than that of random practice; Schmidt(2011) believes this to be true because when performing blocked practice the performer doesn’t feel the need to solve the problem during each re-take of a situation as they seek the solutions they found on earlier shots.
Session Plan 1 - Blocked Practice
During the first session it is important for the coach to allow the athlete time to practice with no obstruction as Bortoli(1998) suggests a high amount of repetitive practice as an important pre-requisite when sustaining confidence. Confidence is an important area to focus on when training as Burton et al.(1988) considers those who have high self-confidence to perform better than those who do not.
Session Plan 2 - Blocked Practice
When
comparing figure 15 to that of figure 5 it is clear to see the necessity on
keeping the back straight when performing this technique. In order to progress
the athlete it is important to change the environment to change behaviour. A
wall was added to enable the client to become accustomed to a match specific
environment when practicing this skill in order for them to be able to perform
this during a match.
Session Plan 3 - Random Practice
 |
| Figure 18: Session plan 1 - Blocked Practice |
During the first session it is important for the coach to allow the athlete time to practice with no obstruction as Bortoli(1998) suggests a high amount of repetitive practice as an important pre-requisite when sustaining confidence. Confidence is an important area to focus on when training as Burton et al.(1988) considers those who have high self-confidence to perform better than those who do not.
Session Plan 2 - Blocked Practice
 |
| Figure 19: Session Plan 2 - Blocked Practice |
Session Plan 3 - Random Practice
 |
| Figure 20: Session Plan 3 - Random Practice
Wrisberg(2007)
suggests that once the performer understands the technique involved, random practice
should be used to merge the newly learnt behaviours in to a match specific
situation. As figure 20(above) shows, the athlete is now using random practice
to increase the efficiency of the behaviour learned previously whilst changing
the environment.
|
Athlete after intervention
When
looking at the changes in behaviour of the athlete from video 2 it is clear to
see the technique’s which were learnt using coaching interventions have been
combined with the technique the athlete already had possessed prior to the
intervention. The athlete now keeps their back straight throughout the striking
action which allows for the ball to travel in the motion require. Also the
athlete now follows through with more aggression which again allows for the
ball to travel at higher speeds.
Plan-Do-Review
 |
| Figure 21: Plan Do review |
Lyle
and Cushion(2010) suggest that good coaches use the 'Plan-Do-Review' cycle as
this allows them revert back to the original plan at regular intervals which
allows for change and implementation if needed. Furthermore, Robinson(2014)
believes that coaches are 'ineffective' unless they fully understand and
incorporate the use of the self-reflection in order to improve coaching
practices. Planning is amongst the most important areas within the coaching
process (Foxon,2001), so when the sessions were planned it was firstly
important to consider using either random or blocked practices as both provide
advantages and disadvantages. Then when carrying out the sessions with the
athlete, demonstrations were done in both real time and slow motion using
pictures and videos as this can aid the athlete when learning the technique and
then finally acquiring the speed and rhythm of the actual skill(Scully, 1988).
Finally when reviewing the sessions, Amory(2011) proposes that the coach must
also review the process as well as the sessions they have provided. When
reviewing the process undertaken, the plan-do-review cycle has been followed
which allows for the coaching process to be repeated and change to be
implemented. When delivering the sessions, the athlete has gained a high level of
confidence through the high volume of practice they achieved during the
sessions. This has allowed for the athlete to develop the skill which; during
consultation was described by the athlete as being 'inadequate' and an area for
improvement.
Summary
Whilst
undertaking this pedagogical process it has been a great learning curve for
both coach and athlete. The athlete has learnt the importance of prescribed
practice sessions which allow for development and confidence recruitment; this
has enforced them to start practicing on a regular basis using sessions which
were created by the coach prior to the end of the intervention. The coach has
learnt the importance of the Plan-Do-review cycle and the bearing this has on
future sessions as well as the process taken in order to carry out these
sessions. The coach has also learnt the detrimental effect confidence can have
on an athlete and how this can change behaviour negatively, which can then
effect the technique of an athlete subconsciously.
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