The science of the golf swing

By Jason Hutchison, M.D.

In 1992, a golf pro named Jim McLean theorized the merits of the so-called, “X-factor” concept as it relates to driving distance.

This theory hypothesizes that the magnitude of the upper body coiling during back swing and the velocity uncoiling during down swing have a large impact on club head speed and ultimately ball velocity. Although this concept has been recognized by golf instructors for years, it has only recently been borne out in the biomechanical research on golf training and performance.

Recent advances in high speed cameras and motion analysis software have allowed pioneering research into the science of the golf swing. At the forefront of this research is the University of Pittsburgh Medical Center’s golf laboratory.

In a recent study of 100 golfers, researchers at the golf laboratory were able to definitively confirm the “X-factor” as a major component of ball velocity and, therefore, driving distance.

Several things were noted to contribute to the “X-factor” as described by McLean.

First, the ball velocity was directly correlated with the number of degrees of separation between the plane of the upper torso (shoulders) and the plane of the pelvis during maximum back swing. The difference between the rotation of these two planes can be described as coiling. In short, the people who coil the most tend to uncoil with greater velocity.

Another interesting finding on ball velocity and biomechanical swing analysis relates to the wrist hinge angle before impact. This study looked at 109 right-handed golfers who were categorized as low, medium or high velocity ball strikers.

The study focused on the wrist hinge angle and how it changed throughout the swing. This study conclusively found that the golfers who maintained their wrist hinge angle longer during the down swing were significantly more likely to be high velocity ball strikers.

After compiling the data in this study, researchers suggested that the wrist hinge angle should be maintained as long as possible in order to maximize the whip effect of the golf club at impact.

Certainly much of what has been identified in the swing analysis laboratories has only confirmed or enhanced what has already been known by golf teachers and coaches around the country.

However, as the evidence becomes more concrete and quantifiable with regard to the contribution of different biomechanical factors, golf coaches and trainers are beginning to take advantage of this knowledge and institute unique strategies to try and maximize performance in driving distance.

These programs now emphasize truncal strengthening and flexibility programs for the neck, shoulders, trunk and hamstring as an integral portion of the regimen. Exercise regimens, which were once designed to generate maximum strength, are now catering more toward maximum flexibility. Furthermore, the before and after testing of golfers who have gone through a program emphasizing core strengthening and flexibility does indeed demonstrate a significant increase in club head speed and driving distance.

One thing is clear in the recent evolution of golf. Golf courses are longer and golfers are hitting longer. It certainly seems clear that it is the golfers who are pushing the courses longer. Tour professionals like Tiger Woods and Phil Mickelson, who have perfect swing mechanics combined with newer technologies in golf club manufacturing, have 300+ yard drives that are now considered routine.

As amateur golfers look to improve their game and maximize distance, the impulse reaction is to buy new clubs and use the latest and greatest technology.

However, as the sports medicine and performance training research data indicate, spinal stabilization, core strengthening and flexibility training seem to be equally integral for generating maximum ball velocity and driving distance.

Core strength and flexibility training also offers an additional benefit that Nike, Ping and Taylor Made will not likely replicate any time soon. This type of training program has been shown time and time again to help prevent and minimize the incidents of sports-related and swing-related injuries.

For most of us, golf is simply a fun, relaxing sport that can be enjoyed at almost any age. To help maximize your performance and also minimize your chance of injury, make sure core strengthening and flexibility are an integral part of your conditioning workouts.