When the athlete isn’t pumping around the race course, they will be in the harness and constantly trying to keep the speed up. This is done by trying to keep the rig upright and still, this allows the power to be kept within the sail and propelling the board forward. People have different stances and movements that aim to keep the rig upright, sheeted in (Closed at the back) and power up allowing them to keep up to speed. “whilst keeping the rig as upright as possible” (S,Bornhoft, 2013) This article shows how important keeping the rig upright is as they have put it in the top 5 musts when linked to upwind sailing this makes it a massive areas for all athlete in the windsurfing field. This rig positioning is heavily controlled by hip positioning and weight distribution compared to the rig, fin and dagger board. “it's your hips that should control both the trim and direction of the board…swing them towards the tail to lift the nose and head up.” (J,Rodhe, 1996) The positioning of the athletes hips can effect the angle of the rig and the trim of the board, making it vital that they try and keep this correct during the time they spend in the harness throughout the race, as the wrong hip angles can effect their over all speed and upwind angles.
Body positing can effect the pressure that is applied against the dagger board, creating the lift needed to yea the board upwind and keep it tracking in a straight line. The more weight put in the harness allows less weight to be places over the board. This is beneficial as it will allow the board to stay at a higher speed. Furthermore bringing the weight outboard and committed it allows the board to remain mainly flat and adds the increased chance that the athlete can use the outboard in order to pull up the windward rail, and engage the leeward rail allowing the board to track further towards the wind.
From the pictures it can be seen that the first athlete (elite model) has a much better rig positing as it is upright and sheeted in. This will allow the athlete to maintain the speed and possibly gain, this speed gain will be a rest of the wind being harnessed and maintained within the sail. Because it is sheeted in and upright it is open to a larger percentage of wind, when a sail is sheeted out and lent over (athlete 2) this causes the wind to flow in and flow straight out of sail, therefore less wind is presented to the sail, causing the board to lose speed (as shown in the graph below).
From the photos and data I can identify that the athlete needs to improve both their hip positioning and weight distribution. Currently their hip positing isn't as significant twist as needed (around 45°). This less angled hip twist doesn't allow the sail to be sheeted in fully as the back arm is fully extended at the equal level to the front arm, causing there to be an decrease in the sheeting angle. This decrease in the sheeting angle will allow the wind to escape the sail easily, this escaping wind will cause the sail to lose power quickly as there isn't an enclosed area that will allow the wind to push the athlete forwards. Therefore this hip twist will cause the athlete to lose speed quickly, as illustrated within the graph this athlete lost 0.5 knots over a 5 minute period, this is an average of 0.1 knots per minute, this could be a huge loss across the race course since the upwind legs tend to be around 1KM long, this takes around 10-15 minutes wind dependant so by losing an average of 0.1knots due to their hip positioning effecting their sheeting angle. The speed loss will cause the athlete to lose positions around the race course, leaving them at a huge disadvantage.
Weight distribution is also an area that would need urgent work as their current weight distribution is causing all of their body weight to be on and move the centre/ windward rail of the board. This weight being on top of the centre board, this is reducing the force against the dagger, as there is less force pushing against the dagger board this will reduce the pointing angle of the board as there is less resistance against the dagger. Furthermore the weight being over the centre line is reducing the board percentage in the water increasing the resistance which in turn reduces the speed overall. Similar to their hip positioning this could cause the individual to lose positions during the race and cause them to be in bad positioning, for example if another athlete has a better wight distribution the this will allow them to sail faster, if an individual sails over to top it will effect the wind causing the individual to have less and the lose even more speed.
If the weight distribution and hip positing are correct this will give the athlete the best speed advantage over the other competitors. This speed advantage can also he advantageous when it comes to work rate because this will allow even more of a speed advantage as their starting speed is higher the pumping will accelerate this. This will also allow the athletes to be the decision maker in different situations as they will be slightly faster allowing them to force the other competitors into making different movements (e.g. tacking to the other side) as they can accelerate away from them. Therefore giving them the best advantage and chance around the race course.
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