In our Baseline session, we have golfers take single-arm swings with both their trail arm and lead arm. This allows the app to assess the potential of a Single Arm Enhancer program to increase a Stacker's clubhead speed. It is possible for one of your arms to be a limiting factor in your speed development. Perhaps you've completed a Baseline (or Progress Check), noticed a significant difference, and are wondering why the app didn't recommend a Single Arm Enhancer program?
This FAQ will answer that question, but first, let's provide some background on this topic.
The image below shows that 93% of Stackers play golf with right-handed clubs. Within this group of right-handed golfers, 95% would choose to throw a ball with their right hand. Most people consider the arm they would choose to throw a ball with as their dominant arm. Therefore, for 95% of right-handed golfers, the trail arm is considered the dominant arm. Do you believe that these golfers would tend to generate faster single-arm swings with their trail arm?
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The next figure shows that golfers who have the trail arm as the dominant arm are just as likely to be faster with the lead arm when making single-arm swings. It is also interesting to note that approximately 20% of golfers have a difference of at least 10 mph between single-arm swings with their lead arm compared to swings with just their trail arm.![]()
The app uses complex algorithms with numerous data inputs when creating the rank-ordered list of programs following a Baseline (or Progress Check) session. Effectively, each potential program is given a score, and then the programs are listed from highest to lowest score. The score for single-arm enhancer programs is primarily based on two inputs:
- What is the speed difference between the arms when making single-arm swings?
- What is the speed difference between the single-arm swings and normal swings?
As with all of our programs, the equations representing these scores have evolved over time based on the measured effectiveness of the programming from tracking tens of thousands of Stackers.
Assume you have a large speed difference between arms in a Progress Check. Let's say your lead arm is 15 mph faster than your trail arm. You expect the Trail Arm Enhancer Program to be recommended by the app, but the app recommends Full Speed Spectrum instead! This is fine. It simply means that the app has computed that Full Speed Spectrum will likely increase your speed to a greater extent, at this moment in time, than will a Trail Arm Enhancer Program.
We strongly encourage Stackers to follow the app's recommendations. We can compare Stackers that do NOT follow our recommendations to a matched group of Stackers (age, starting speed, handicap, number of completed programs, gender) that follow our recommendations. On average, the Stackers that follow the app's recommendations gain 70% more speed! This is not surprising as our programming is continually being optimized.
That said, motivation and engagement are important factors in the success of a training program. If you are a longtime Stacker and are interested in trying a program that's ranked 2nd or 3rd on the list, then you should give it a go!
As an aside, it's interesting to note that golfers with the lead arm as the dominant arm are much more likely to achieve higher speeds with the lead arm when making single-arm swings.
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