Theses notes are part of the course “Basic principles of movement analyses and how to build up new patterns of movements.” – Fysiofit Sportcentrum - Sint Niklaas Nov 2003/March 2004 –
In order to improve the performance of a tennis player it is needed a protocol of what is important to observe
The main aspects chosen are:
When we warm-up the movements we choose depend of the subject we will deal with during the training session.
If it is a pre-match warm-up the movements used will focus the body connections we need to play the game.
In this session we will deal with the aspect grounding so the w-up will focus specifically this aspect.
We take our shoes off and stay in a circle.
We have to pay attention in feeling our feet.
We shift our body weight slightly on one foot and we stand in the outer side, tucking our toes under (plantar flexion).
We realize that the knee starts to move to the outside and the hip moves backwards.
Then we move the foot in the opposite direction (foot eversion) and we observe the knee and the hip moves in the opposite direction as well. We do this 8 or 10 times.
We walk in circle and we feel the difference between the trained foot and the other one.
We repeat the same movement with the other foot and then with both simultaneously.
We alternate both movements (one foot in plantar flexion meanwhile the other one in eversion) to walk in place.
The jogging activity or ball training begins after and the grounding is different in terms of:
When we want to know about how a player can generate speed and strength we have to look how she he /uses the ground (grounding). This depends on 3 aspects:
Which foot gives support to the movement.
In what sequence the different parts of the foot contact the floor.
Where is the foot pointing to facilitate hip rotation.
It is essential to understand how each possibility of grounding depends on and condition the game situation
Light and short grounding (see Tim Henman in the return, pic. 1) or a strong and longer (in time) grounding (see Boris Becker in service, pic. 2).
A stronger contact with the ground provides more stability and control meanwhile a lighter and quicker contact could be used when the player has to deal with a short time availability to play the ball.
Short contact (picture 1)
Long contact (picture 2)
If after the precedent w-up the player can feel with which kind of contact he feels more comfortable in each technical action. Then next exercise makes sense.
We ask the player to strike using the 3 options: heel-plant contact, plant, and balls of the foot.
We play standard balls variating speed, length and height. The player must use a strong grounding. The amount of balls should be enough to allow the player to compare the results of his action and thereby to have a coherent vision about in which situation it was a good solution and in which not.
The same procedure is repeated using light grounding.
Now that we have analyzed the grounding aspect we continue to hips. There is a logical continuation of how the feet are placed.
Who in open stand with the foot point out the net try to turn the hips (opening) will find that the range of movement at that level (hips level) is minimum.
For spreading the lower part of the body it is necessary external rotation at femoral joint level.
If proximal initiation is chosen it will bring the foot to turn outside.
If distal initiation is chosen the foot will bring the leg to external rotation.
We start sitting in order to clarify the external rotation of the lower part of the body.
Pic. 1: from starting position (attention phase) with neutral posture the player finds core support.
Pic. 2: pushing from the left foot and shifting weight to the right sitz-bone (ischial tuberosity) the right hip retreat and the right leg and foot turn out.
Pic. 3: body weight on the right foot the hips are ready to initiate the rotation to perform the stroke.
Wrong open stand (Picture 1)
Correctopen stand (Picture 2)
The feet and hips position for backhand of a left-handed player in open stand is the same than for a forehand of a right-handed player in open stand.
In this backhand stroke can be seen how the foot position conditions the hips movement.
In pic. 2 can be observe that both feet are more or less parallel to the base line.
To improve hips control and stability.
To clarify the connection between foot word and hips turn.
Sit on a chair, back straight and without support, both feet placed on the floor a bit larger than hips width.
Left foot increase pressure on the floor (thrusting leg) and left hip moves forward sliding on the chair.
As a consequence of this movement the right hip moves backwards. This brings the right leg to turn out and the right foot to leave the floor.
Planting the right foot on the floor go to standing without extending completely the legs.
It is through pushing into the floor that we place the opposite hip in the right position.
The use of the chair reveals the development aspect of the approach to teach sport actions.
Pic. 1: Starting position: seated on a chair
Pic. 2: For coming to stand the player turns to the right pushing from the left foot: priority direction = sideward.
Pic. 3: The player stands up maintaining certain degree of hip flexion (femoral joints) and his arm is ready for the swing. The coach is ready to throw a ball.
Pic. 4: The coach throws the ball and the player (in open stand position) starts turning the right hip forward. The hip takes the arm to swing forwards.
Pic. 5: The player hits the ball and simultaneously the coach drops another ball at 3 m. from the player.
Pic. 6: The player continues the movement forwards and touches the second ball. The player is compelled to keep on moving forward (Follow through after the Main action) and goes “into the ball”.
The whole movement is a spiral one.
From the observation of the three aspects could come out the fundamental points to work on.
The exercises proposed are just examples what could be done when the aspect to be corrected is found.