If you want to read the abstract of the study before reading my analysis click here.
This study is very intriguing for a couple of reasons. One, it is the first of its kind to relate physical limitations identified in the body from the Level 1 screen and relating it to swing characteristics seen on video analysis. Previous studies have looked at flexibility and strength training on golf performance, mostly driving distance but none have looked at how flexibility and strength relate to mechanics of the golf swing. Two, the study comes out of my alma mater, Grand Valley State University, and to be the first study of its kind is special to me. TPI has done all their own research in which they base the information from their seminars on. They do not publish results but rather give the data and results at seminars. This is the first study of its kind to confirm their findings.
The study included 36 male and female golfers with a handicap average of 14.2 +/- 10.4. The golfers were assessed using the TPI level 1 screen, consisting of 12 tests which assess strength, flexibility and balance and then were recorded for video analysis hitting 4 shots with a 5 iron. The current level 1 screen contains 16 tests with 1 optional test.
For more information on what the 12 tests of the TPI level 1 screen consist of click here. The most common dysfunctions found in this study include the overhead deep squat, toe touch, single leg balance and single leg bridge.
For more information on the different swing characteristics click here. The most common swing faults in the study are hip early extension, loss of posture and slide.
The results confirm what TPI teaches at their seminars and from what I have read and understand about the golf swing. I am a credible source on the body and golf swing as I have an Undergraduate degree in Biomedical Sciences and am in the last year of my Doctorate in Chiropractic. I also have played golf for 20 years now and carry a 0 handicap. I am also level 1 and 2 TPI Medical Professional certified and have read many books and research on the mechanics of the golf swing.
The most common physical limitations in the body were the overhead deep squat, toe touch, single leg balance (both legs) and single leg bridge (both legs). The most common swing characteristics were early hip extension, loss of posture and slide. Statistical analysis showed there were 3 significant associations between physical limitations and swing characteristics.
- If a golfer cannot touch his toes, the golfer is 6x as likely to early extend hips on the downswing. 14 out of the 17 showed early extension on their golf swing if they could not touch their toes. This is the highest association and percentage between a physical dysfunction and swing fault at 82% for touching toes and early extension.
- A golfer that cannot single leg bridge on the right side has a 6x more likely chance to lose posture during the golf swing. In other words you have a 68% chance of losing your posture if you cannot bridge on the right. 17 out of the 25 golfers who could not bridge lost their posture.
- A golfer that cannot single leg bridge on the right side will also extend hips 5x more likely than somebody who can. 18 out of the 25 golfers who could not bridge on the right early extended. This is a 72% chance that you will early extend.
For a quick recap, early extension often causes the golfer to become trapped on the downswing leading to a tendency to hook the ball or block the ball to the right. Loss of posture during the swing can cause the golfer to lose power, consistent ball striking and can also cause the golfer to become trapped. Visit the links above for a more detailed explanation of early extension and loss of posture if you do not understand these swing characteristics.
Other points worth noting:
- Inability to balance on the left leg causes you to 3x as likely early extend (75%), lose posture (70%) and/or slide on the downswing (45%).
- Golfers who cannot overhead deep squat have a 2x more likely chance to early extend (67%).
- A golfer who cannot balance on the right leg has a 2x chance of loss of posture (57%).
- Inability to bridge on the right can cause you to 2x as likely slide on the downswing.
Here’s what the study means to your swing:
- Early extension causes you to become trapped, leading to hooking and blocking it right. Having 2 different misses is not good for your golf game.
- Loss of posture causes a lack of power and leads to inconsistent ball striking. It can also cause you to become trapped and have 2 misses (hooking and blocking it to the right).
- Slide can cause you to lose power because you cannot transfer energy created from the hips to the upper body and eventually to the ball.
Here’s what the study means to your body:
- Early extension is one of the leading causes of low back pain in golfers according to TPI.
- Right glute strength is very important to prevent you from losing your posture, to prevent your hips from extending on the downswing and to keep you from sliding into the golf ball on the downswing.
- Being able to touch your toes can help keep you from early extending the hips. Touching your toes involves a proper hip hinge as well as flexibility in your posterior chain (hamstrings and calves). Read about the importance of the hip hinge to your golf swing and body here.
- Balancing on your left leg can keep you from extending the hips, losing your posture and to keep you from sliding into the ball. Balance is also very important to help reduce your risk for falling at home.
- Inability to squat can cause you to early extend and lose posture 67% and 54% respectively.
Being screened by a TPI professional is important to figure out what exactly your deficiencies are in your body and what they may be causing in your swing. However, if you would like a couple exercises to do at home or at the gym to help your glutes, balance and toe touch, here are a few of my favorites:
- Glute strength
- Toe Touch
According to TPI’s research early extension is the most common swing fault in amateurs and is confirmed by the study. The study left me wondering if sex, age, height, weight and/or handicap level affected being able to complete a test or having a certain swing characteristic. However, this was not the purpose of the study, but future studies could examine this. Also, 36 golfers is a very small sample size, however being the first study of its kind, this is expected. Future research should include a bigger sample size and include more analysis of the data. TPI’s data includes thousands of golfers both amateurs and professionals.
An interesting conclusion drawn from the study, which differs from TPI’s belief, is lead hip (left for right handed golfer) internal rotation did not correlate to sliding in the downswing. In other words if the golfer cannot turn into their left hip, they will have to slide to the left in order to hit the ball. TPI believes that the most common cause of slide is a lack of lead hip internal rotation, however, the study found that there was no association between the two.
The test used in the TPI level 1 screen to assess hip rotation is the lower quarter rotation test. This test is good for a basic assessment of rotation in the lower body, but does not isolate pure hip rotation, as this test includes other variables such as ankle mobility and tibial rotation. Future papers should look at more specific testing on isolated hip internal rotation and sliding in the golf swing.
In my opinion I trust what TPI teaches because of the massive amounts of data they have gathered, their experience in working with thousands of golfers and the fact that they have access to 3D biomechanics equipment and slow motion capture which the study did not have or used. The author states this could be due to the lower quarter rotation test not being sensitive or specific enough for limited internal rotation during the swing.
My final thought is this is a great start in order to further close the gap between the body and the mechanics of the golf swing. The TPI level 1 screen is only meant as a basic assessment to address ranges of motion needed for the golf swing. TPI has a more advanced method of testing, called the SFMA (selective functional movement assessment).
Further research should include a larger sample size, more statistical analysis, more specific physical testing (like the SFMA) and 3D biomechanical analysis in addition to the 2D analysis with video. I recommend every golf teaching professional should read this paper and try to understand further how the body relates to the golf swing. And if more information is needed, attend a TPI seminar!