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Making an online takeaway is an absolutely vital element in being able to make great golf swings that produce consistency of strike, power and accuracy in your golf shots. Your takeaway is the initial movement that you make with the golf club and if you can make an online takeaway, you have a great opportunity to keep the rest of your golf swing on plane.
Your swing plane is the angle that you swing the club head around you on. To make an online takeaway, this simply means that you move the club head back away from the golf ball on your plane line. You can get a great idea of how to do this by using an alignment pole. Take up your address position so that you are ready to play a golf shot. Now push the alignment pole into the ground so that it enters the ground where the club head is. Push it in at an angle to replicate the angle that the shaft of your golf club is set to the ground at. The pole is now showing you your plane line, or the angle you want to work on moving the club head around you at.
If you take a large step to the left of the pole (right handed golfers), keeping the club head in line with where the pole has entered the ground, you can now practise your takeaway and make sure that it is online. Simply move the club head away from the golf ball so that it follows the angle of the alignment pole. Doing this should see you get the club into a position where the shaft of the club is parallel to the ground at around hip high. At this point, the shaft should also be parallel to the target line as well and if you have achieved this position, you will have made an online takeaway, setting you up to continue swinging online and therefore allowing you to make a great golf swing that produces consistent, accurate and long golf shots.
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Pulling the club head inside the target line will result in you swinging the club head under plane – or below the alignment pole. With this action, you have a flat takeaway rather than an online takeaway and you will now have to make compensatory and additional movements in your golf swing in an attempt to get the club head back in to the correct position to strike the golf ball from.
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If you swing the club head really high then your takeaway will be above plane, or steep and not online. This will result in you experiencing less rotation in your torso on your back swing and you will not strike the ball as consistently, as far, or as accurately as you potentially could.
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Your golf swing is a rotatory, arcing movement and even though you are wanting to swing as directly along the target line as possible, for as long as possible, your swing is not made up of straight lines but of an arcing lines. Take the club head back along the target line on your takeaway but it must curve in off this at some point.