Art, I'd like to pow-wow with you again down at Marbella. BBKIB works like a charm for so many people. Maybe we can get a few of my students to participate in a clinic.
Dear Billy,
I had a PM that requested some background on BBKIB for clinics he was leading for adult men and women.
I prepared the response noted below and am attaching it here in hopes that it also may be of value to you and other instructors.
Thanks for letting me piggyback on your post again.
Sincerely,
art
BBKIB BACKGROUND
During the down swing of all golfers, the rotation of the hips, torso arms and club develop significant forces that in total, tend to PULL the golfer out of their stance, kind of over the ball and line to the target.
As a useful example and test, try putting your feet together, and with a club in your hands take HORIZONTAL swings back and forth, NOT stopping for 5 or more complete cycles. Note the way in which you FEEL these disturbing forces trying to PULL you around, especially at your highest rotation rate.
Believe it or not, for a slow 70 mile per hour swing speed, each of these forces, including the club itself can develop up to 50 pounds of ‘centripetal’ or reaction force the golfer must control for the club to stay on a desired path to the ball. For a 100 mile per hour swing speed, unbelievably, these forces DOUBLE and must be accounted for and accommodated to develop a quality golf swing.
So, in reality, during the down swing, large forces develop from the rotating parts that have the effect of pulling every golfer away from their desired paths of rotation thereby affecting the quality of the swing path and resultant shot.
A review of the literature including videos of professional golfers indicated that the ‘corrections’, needed to overcome/control these disturbances seemed to be coming either during the back swing and/or transition to the down swing.
In further researching this area of ‘golf swing dynamic balance and stability’ it also appeared that a significant amount of time PROBABLY was required to ‘train’ the body by ‘trial and error’ to compensate DURING THE SWING. However, science and engineering experience suggested that the possibility of simply ‘biasing’ the set-up position to ANTICIPATE these pending dynamic unbalancing/disturbing forces could be much more expedient and easier to learn.
An extensive review of foot reaction forces and their movement during the golf swings of golfers of all capabilities clearly supported the concept of ‘biasing’ the set up position by placing the “BUMPY BACK, BB”. How far, became a ‘golfer-unique’ aspect of the research, and remains a task for the instructor/science advisor based on the magnitude of disturbance from each rotating element of the golfer’s body. BUT, and a big BUT, any degree of BB provides positive restoring/compensating dynamic characteristics so IMO it should become a UNIVERSAL change for all golfers.
With regard to “KEEP IT BACK, KIB”, this is an upper body dynamic stability issue, and not quite as severe a need as a significant percentage of golfers already control this area adequately from previous lessons, practice, play etc.For overall stability however, IT IS MANDATORY that every golfer does KIB at least at through transition, and the start of the down swing.
Other, less stable golfers will have to try to KIB longer, but realize that the human body will NOT allow the right (rear) hip/Bumpy to remain back for the entire down swing. In fact, the science of dynamic stability requires the need for the initial down swing rotation to center nearer the rear hip joint and move towards the front hip joint before impact allowing the trail/ rear heel to come off the ground and flow into the follow-thru smoothly. So in a simplified sense, during the start of the downswing, the lead hip rotates counterclockwise for a right handed golfer, with the trail hip ‘following’ and eventually rotating towards the target, around the lead hip joint.
Finally, BBKIB when performed correctly for each golfer results in dynamic balance and stability improvements, AND has consistently produced increases in club head speed (distance) of 5-10%, , and reductions in dispersion around the target of 25-50%.
