Grip strength and grip pressure have become hot topics of research and golf instruction over the past few years. Partially this is due to the advancements in technology that have allowed measurement on the handle and partially just due to the deeper dive of all things data related to performance in golf. An understanding of the role of grip strength and grip pressure for golfers of all skill levels is an important aspect of improving golf performance. This article will cover some of the definitions and terms related to this topic, present some ideas related to golf performance and present some data collected in this area.

Strength vs pressure - One of the first areas that is critical to understand is the difference between grip strength and grip pressure. Grip strength in a simple way is defined as the amount of strength a person can produce with the muscles related to the grip. The most common measurement tool for grip strength is a dynamometer. This is a device that a person can hold in their hands and squeeze as hard as possible to record a maximum value. Typically these measurements are recorded in pounds or kilograms and give a measurable value of how strong a person can grip something. Grip pressure is defined as the force exerted per unit area, or how much force a person is applying over the different areas of the grip in the golf club. Often the idea of grip pressure is looked at as how hard out of 10 is a person “squeezing” the golf club during a golf swing, whereas grip strength should be thought of as simply how strong a player's grip muscles actually are. 

Measurement of grip pressure - Grip pressure in the past has been an extremely difficult variable to measure, especially dynamically during a golf swing. Researchers have used modeling tools and various pressure sensor based tools to estimate and measure grip pressure during the swing and have added to our understanding of this question. Recently, instrumented grips have been developed which actually contain force sensing devices inside of the grip to measure forces and pressures in the handle during the swing. While also with limitations, this device has led to more understanding about what is actually happening at the grip during the golf swing.

Grip Strength Importance - The actual raw grip strength of an individual plays an important role in many aspects of the game of golf. One study we conducted measured grip strength using a dynamometer on the tee of a Par 4 in a local fundraising tournament. Players would then hit a drive for maximum speed while Trackman measured club metrics. The study found a correlation between grip strength and swing speed in the nearly 100 golfers who participated in the study. The correlation value was almost 0.7 and was found to be statistically significant. It should be noted that studies have also shown that grip strength is correlated to overall body strength, but it is important to first note the relationship between all of these variables. As such grip strength should be thought of as a piece of the puzzle when considering swing speed. Further data supports this when looking at the grip strength of long drive competitors and PGA tour players who tend to swing the golf club much faster than amateur players. Long drive players have grip strength averages that are above professional players who then have grip strength averages that are above amateur golfers. 

If you have recently played golf with an older golfer or junior golfer who struggles to get the ball advanced out of rough, you will understand another important aspect of grip strength. Getting the club through long, thick rough requires more grip strength to advance the ball further. Younger golfers and older golfers tend to have less grip strength and struggle greatly to get the ball out of the rough. Think also of videos of your favorite professional player hitting a ball out of US Open rough or British Open long grass and you will notice how activated the forearm and hand muscles appear to be during those swings. They are not passively holding onto the club, but instead are firmly holding onto the club to ensure proper contact with the golf ball. 

Preventing club face twisting is a key for golfers to reduce the gear effects associated with off center hits. When a player hits the ball perfectly square off the club face, there is limited torque that is trying to create rotation of the club face. Unfortunately for amateur golfers, off center hits are commonplace during a round of golf. The advancements in club design to create club heads with moments of inertia (MOI) that are larger to help prevent the club from twisting have made this problem much easier to handle with the correct equipment. Another way to limit some of this is by having enough grip strength to prevent unwanted twisting of the grip and then the club face at various points of the swing.

Grip Pressure During the Golf Swing - Measurements with the SensorEdge instrumented grip have provided further information about the pressures applied to the grip handle during the golf swing. Some of the questions that are starting to be answered are differences in pressure between various points in the swing, how much pressure is actually applied, differences between fast and slow players, variations between highly skilled and low skilled players and even how various shot distances alter pressure during the swing. 

Typically you can think about the times that the club has to start movement and change directions as two places where some larger pressures need to be applied. First would be to start the club moving in the backswing and the other would be as the backswing ends and the player starts to initiate the downswing into about club vertical on the downswing. These two areas tend to be the areas where more pressure is built in the swing. Often that pressure will actually fall off a bit from its maximum value as the club comes into impact. These pressures can peak at a 7 or 8 out of 10 for a lot of players. This suggests that if they could apply 50 kg of force, they would be using almost 75% of that available force at the maximum points in the swing or 37.5 kg. This is important because if a player can only apply 35 kg of force, they wouldn’t be able to get to 37.5 kg of force in the swing, at 100% they would only be at 35 kg. We know there are certain force values needed to hold onto a club at various swing speeds and so this could become a limiting factor in swing speed production.  Our data collections haven’t seen a lot of 5 out of 10 peak values for golfers regardless of skill level or speed. There may be a slight trend towards players with greater grip strength having slightly reduced pressures during the swing. Below is an example of this principle. Two players with similar body sizes and club speeds analyzed for grip strength and pressure during the swing. One player was able to generate 69 kg during the calibration of the SensorEdge instrumented driver. This was done by having the player squeeze as hard as possible with both hands. The other player only produced 55 kg. During the swing their maximum force during the swing was a little reduced in the stronger player (39 kg vs 44 kg). What really jumps out is the % of their max used during the swing, with the stronger player at 5.7/10 and the weaker player at 8/10. This shows how a stronger grip player could produce greater amounts of force with less pressure during the swing. You can see similar results on their sensor edge data below as well, showing a great percentage of max individual hand force during the swing.

The stronger player above at maximum value had 68% of max from the lead and 52% of max from the trail. The weaker player below had 95% of max from the lead and 76% of max from the trail.

Fast players tend to just apply larger raw force values and even greater pressures at various points in the swing. Not all will do this, but often this is the case, as the pressure value can get near a 10/10 at peak pressure values, again usually occurring in the early downswing. 

Highly skilled players tend to have a nice pattern as described above, with the force having times where it builds slightly and then drops slightly. Lower skilled players tend to start out a bit lower at address and then apply a lot of force, leading to high pressure values that often remain throughout the swing. Almost uniformly players apply more pressure from the lead hand compared to the trail when thinking about the distribution between lead and trail hands. Meaning they are applying more from the lead hand than the trail hand throughout the swing. This is definitely a more prominent pattern in better players. Occasionally we have seen players with weaker grip strength apply more equal pressures between both hands, or get more active with the trail hand in the early downswing as well. This is an area that we haven’t done as much analysis, but great work has been done by Carson Hau and Liam Mucklow at the Golf Lab in Canada who are another great resource for these types of data collections. The same would be true of their work looking at drivers, vs irons, vs chip shots. They have great information related to these different shot variations, whereas all of our data collections have been conducted with a driver. 

Training Grip Strength - We have conducted a few small pilot type studies with limited subjects to understand what happens when golfers are able to increase their grip strength via training. While there are many avenues to train grip strength (lifting heavy things, farmers walks, grip training aids) we have focused our research on the use of the SuperSpeed Squeeze as the training stimulus. In the first small study we looked at how training grip strength in isolation would alter swing speed. In a group of 8 golfers we were able to see about a 5-7% in grip strength depending on hand analysis over the course of 4 weeks. Swing speed increased by nearly 2.0 mph in the study. This group was a mix of males and females and did contain a few older golfers as well. More studies such as this need to be conducted to understand how training grip strength in isolation could alter swing speed and performance. 

Another study done in collaboration with Paxton Clabaugh looked at what occurred in the SensorEdge data when four golfers trained with the SuperSpeed Squeeze over the course of a 5 week period. These players on average were able to increase their grip strength by nearly 14%, with a high of 20% and a low of 5.4%. SensorEdge data collected showed one common occurrence in all of the players, which was a more stable pressure trace over the course of the entirety of the swing. One player who tended to be more equal in pressure from both trail and lead was able to apply more pressure from the lead side during the swing post training. That player happened to be the one with the largest increase in grip strength at 20%. This is a great starting point to build upon with more subjects to understand if these changes would persist among a larger group of participants and also what would be the changes in the club delivery and ball flight. 

The pre sensor edge data shown below

The post sensor edge data with more smooth curves and a bit more separation from lead to trail below.