The 84 Degree Secret Explained
June 24th, 2009 | 
Author: The most interesting discovery I made when studying the top golfers of all-time for Its All About Impact was the 84 degree secret. It is uncanny how different all their swings are yet the vast majority of them find a way to obey this important element in the swing.
It Starts at Address....
Please keep in mind that the 84 degree line is only important as it pertains to impact. It serves to position the weight correctly throughout the swing so that the body can easily glide into the proper impact position.
As you view the picture above picture a line running up this golfers right side (left as you view it). The line forms an 84 degree angle off of vertical (90 degrees). The line should run up the outside of the right leg, cut through a portion of the shoulder and just barely graze the side of the head. When studying swings I started to use this line to isolate body movement and quickly found it to be a good guide for the address position and as a player approached the top of the backswing.
At address the head should not break the line. I noticed with golfers who had too much tilt at address this was quite prevalent and they all had a difficult time assuming the proper impact position once they had started poorly. Notice the picture below.
Too Wide and Tilted
Another common fault was breaking the 84 degree line in the backswing with too much lateral motion. This fault very often originates with too much tilt at address. Try to feel centered over the ball throughout the backswing. Keep in mind that this can be done while still maintaining a sense of loading into the back side or leg. Notice the picture below….
Too Much Lateral Motion
I have found that an excellent drill that conveys the appropriate feel is the ball drill pictured below. Position your back foot up against a wall and place a basketball or soccerball between your head and the wall. Crossing your arms across your chest, pivot into your back side feeling the wind and torque in your core muscles. Hold the position at the top to absorb the sense or feel you have. This is what the body should feel like when it is correctly positioned to compress the ball at impact!
84 Degree Drill
Posted in Long Game, Swing Philosophy | 
Tags: 84 degree secret, address position, backswing, centered, compress the ball, impact, impact position, stack and tilt, weight shift
I have studied many swings of players on the tour and so far have found the 84 degree guideline to be valid and consistent. Great players swing the club back in a relatively confined space with little wasted motion or movement. On the downswing they tend to move forward very aggressively with the core or center of the body. Jim McLean has said that good players tend to under use the body on the backswing and over use the body on the downswing. Poor players do just the opposite. In a false sense of trying to create power in the backswing they tend to over-turn, sway, or do both. On the downswing, they don’t create enough lateral-rotary motion with their bodies in transition and into impact, thus making a weak pass at the ball dominated by their hands and arms.
I have found the 84 degree rule to be very consistently obeyed with iron shots but have found some exceptions to the rule with players hitting drivers. I beleive that the reason for this is that some players attempt to hit “up” on the ball with today’s large headed drivers in an effort to get more air time and more distance. Since they are not trying to compress the ball into the ground,they tend to have more lateral motion with their upper bodies on the backswing in an effort to get “behind and under” the ball. There is much more margin for error on where the driver bottoms out since it is sitting on a tee. An iron shot requires a great deal of precision regarding the low point of the swing. No good player has ever attempted to hit “up” on an iron shot and therefore tends to stay more centered during the backswing.
Brian, you should look into doing this for a living!! I agree with you on the driver and would like to add that the wider stance also plays a role. It essentially shifts the 84 degree line out away from the golfer making it easier to move the upper body in a more lateral fashion in the backswing and hang back and hit up on the ball in the downswing. BTW, the PGA Tour average for attack angle (hitting up or down) is -1.3 degrees. The majority of tour golfers actually hit down slightly on the ball!!
Very helpful to have you explain this all important set up position. Hey, 69 in the the first round of the Rice Planters, not bad for an old guy!
The ball drill illustration looks exactly like Stack and Tilt (which I am doing): back leg is straight (or straighter) with the tilting of the spine down and forward. Where and how much weight would be in this picture then in terms of percentages? I do like the 84 degree idea!
Hi John – the weight is actually 80/20 in favor of the back foot near the top of the swing….read my article on weight transfer!