To get the feeling of both tension and strength, simply stand up and hang your arms at your side.  To feel tension, extend your arms downward to the ground as far as they go.  As you do this, you will feel tension in your arms because they are stretched to their longest point.  Now to feel strength, make two fists and squeeze as hard as you can.  These are two totally different feelings that have two totally different affects on your swing. 

This feeling of strength is what most inexperienced players feel when they hit the ball and they mistake it for tension.  They get this feeling because they're trying to hit the ball so hard that their arm muscles lock up.  This feeling of strength is deceiving though because it also gives the person the feeling of power.  If this feeling of strength is removed, the inexperienced player then thinks that they are not going hit the ball as far so, they immediately they tighten up again.

This feeling of strength in your arms will do two things to destroy your swing:

1. It will narrow your swing arc because the feeling of strength makes your arm muscles contract or buckle through and past impact.  The narrower your swing arc, the slower the club will swing.

2. It will inhibit the hinging and re-hinging of your wrists also resulting in a slower clubhead speed.  The harder you hit, the tighter your wrists will which will also slow the club down.

So how is the clubhead speed increased if you feel tension? 

1.  To achieve the tension I am talking about, you must allow the arms to be stretched out to their fullest through and past impact.  To stretch them out means your muscles cannot be turned on.  You have to keep them loose.  To understand the increase in arc width, imagine that your golf swing is like picking up a weight and swinging it in a circle on a piece of string.  The weight represents your club, the string is your arms, and your body is your hand that is twirling it.  As the weight swings, the piece of string will get tense.  This is because the weight is stretching it to its longest point.  This maximizes its arc.  It's this wide arc that allows the weight to swing its fastest.  Remember, feeling strength in your arms pulls the clubhead closer to you because it contracts your arm muscles.  If your arm muscles contract, it would be like the piece of  string getting shorter as you spin the weight not longer.  The shorter the piece of string, the slower it will swing.

2.  Loosening up the arms, and keeping the muscles turn off, will also loosen up your wrists.  To understand how the wrist hinge will help to create clubhead speed, imagine opening a door with rusty hinges and one with well oiled hinges.   Obviously, the well oiled hinges will allow the door swing open and closed faster.  If your wrists were "well oiled" it would result in more clubhead speed as well.  To get the feeling of wrists that are too tight (rusty hinges), try clenching your fists again.  This time pay attention to your wrists and how locked up they become when you feel strength in your arms.  So allowing the arms to stretch out through and past impact not only maximizes the arc width, but it also loosens your wrists.

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