Bowed (-) / Cupped(+)
Arched (-) / Bent (+)
Address – 24 deg. extension
Top – Less extension than at address
Impact – Almost flat, only 1 deg. of extension
Graph view shows the same swing, but gives a more detailed view of the wrist motion throughout the swing. Vertical axis shows the degrees and horizontal axis shows time.
In graph you can see important details, for instance that the lead wrist was actually flexed (negative) right before impact and was moving towards extension at impact.
On average players are around 10-40 degrees extended at address. Weaker grips have less extension, stronger grips have more.
Top – Stronger grips are more extended, weaker ones less extended, rarely there are cases when players are actually flexed.
Impact usually around zero. Stronger grips have bit of extension (+) at impact, weaker grips are slightly flexed (-).
Hinged (+) / Unhinged(-)
Cocked (+) / Uncocked (-)
Address – Unhinged at address, -30 deg. ulnar
Top – From address added 25 deg. of wrist hinge
Impact – Returned to same amount of ulnar as address, -30
Radial/ulnar deviation measures how much wrists are hinged during the swing.
This depends on individual wrist anatomy and range of motion. Good way to analyze ulnar/radial is to see how much the wrist hinge changes from address to top. This allows to compare player’s who have different wrists and different address value.
Usually players have around 20-30 degree change from address to top. For players with a lot of wrist hinge it can even be 40-50 degree change from address to top. Usually more radial deviation is coupled with more extension of the lead wrist.
At impact wrist ulnar deviation is usually close to its address value.
HackMotion sensor contains gyroscope which measures rotation of the lead wrist in global coordinate system (local coordinate system would measure only wrist to elbow relationship – pronation/supination).
This rotation metric can also be called “global rotation” as opposed to “relative rotation” of the wrist. Since body rotation also rotates the wrist it will also be measured as part of this “global rotation”.
Est. P6 to Imp. – Amount of Rotation from P6 to P7
Imp. to Est. P8 – Amount of Rotation from P7 to P8
Imp. Rot. Speed – Rotation speed at impact, Degrees per second
What are positions P6, P7, P8?
position P6 – Club shaft is parallel to ground BEFORE impact
position P7 – Impact position
position P8 – Club shaft is parallel to ground AFTER impact
To give a quick view of what is happening around impact we have calculated the tile values. These values are not “positions” in golf swing, but instead they measure amount of rotation between 2 swing positions. Please take a look at the graph below to see how the rotation values are calculated.
1. Amount of Rotation between P6 and P7.
For example, 52 degrees of rotation is wrist rotated from -76 degrees open before impact to -24 degrees open at impact (open relative to address position). 76 – 24 = 52 degrees
2. Amount of Rotation between P7 and P8 position.
For example, 66 degrees of rotation is wrist rotated from -24 degrees open at impact to 42 degrees closed after impact (closed wrist relative to address position). 24 + 42 = 66 degrees
3. Wrist Rotation Speed through impact (degrees per second)
Rotation graph shows the rotation of the lead wrist in global coordinate system, taking the address position as its zero reference point and measuring the rotation relative to it.
During backwing the rotation is toward more open clubface position (negative graph value) while during downswing the rotation is towards more closed position (positive value). The values are larger than might be expected because of additional body rotation during the backswing which also rotates the wrist.
Timing of Backswing, Downswing and Backswing/Downswing Ratio
Swing tempo is calculated as the ratio of backswing / downswing. The slower the backswing compared to downswing the higher the ratio.
Swing tempo is very important to consistency. The best players in the world are also very consistent in their swing tempo. Improving the tempo can be a shortcut to better golf and is especially important for short game and distance wedges.
The top of the backswing is identified when the hand movement is changing direction.