Stanford Identifies Key Components to Perfect Golf Swing

Using high-tech sensors on 10 professional players, Stanford University researchers say they have found several biomechanical factors that result in the ideal motion of the hips and shoulders to create the perfect golf swing. These factors separate the elite players from weekend hackers.

By quantifying ideal motions of the important body parts, researchers also found ways to reduce injury, according to a July 30 article in the San Jose Mercury News.

"A golf swing has a lot of moving parts. This gives the scientific foundation to a motion that is very dynamic and hard to measure," Conrad Ray, head coach of the university's Cardinal team, told Mercury News reporter Lisa M. Krieger. "It reduces the guesswork."

According to the article (, which contains remarkable graphics showing the ideal swing action, the study took place at the university's Motion and Gait Analysis Lab, with the test subjects swinging a 5-iron at ping-pong balls on a linoleum floor wearing only shorts and dozens of small silver light-reflecting balls. The volunteers were all Stanford alumni and included Will Yanagisawa and PGA Tour player Notah Begay (former Cardinal Tiger Woods was not one of the subjects).

Eight cameras taped their swings and made a digital record that was then compared to the swings of five amateur players who were also part of the study. Not so remarkably, the research team found that professionals' swings were consistent and virtually indistinguishable from each other. And unlike the amateur subjects, the pros always initiated their downswing by rotating their hips.

On impact with the ball, the pros exhibited a 56-degree difference, on average, in the rotational position of the shoulders and hips; a 25-degree upward tilt of their leading shoulder; and a 12-degree upward tilt of the leading hip.

Conversely, the test amateurs had a narrower average hip-to-shoulder rotation angle of 46 to 48 degrees, which caused them to hit the ball more slowly. And they tilted their hips and shoulders too much, or not enough. Some twisted the upper body with not enough hip turn, a move that cause back injuries to develop.

"We wondered: What contributes the most to hitting a ball hard?" lead investigator Jessica Rose of Lucile Packard Children's Hospital, an associate professor of orthopedic surgery, told Krieger. "With advanced biomechanical analysis, it is now possible to nail down the important elements of the motion."

In some instances, there is no rhyme or reason for the perfect golf swing. "Some great players don't know how they do it. Some know exactly what they do," Ray told Krieger. "This provides science."