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 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.
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. In contrast, local coordinate system measures wrist to elbow relationship.
This rotation metric can also be called “absolute rotation” as opposed to “relative rotation” of the wrist. So a body turn which rotates the wrist away from the address position will also influence the rotation and get measured.
Est. P6 to Imp. – Amount of Rotation from P6 position to Impact P7
Imp. to Est. P8 – Amount of Rotation from P7 Impact to P8 position
Imp. Rot. Speed – Rotation speed at impact. Degrees per second
What are positions P6-8?
position P6 – Club shaft is parallel to ground BEFORE impact
position P7 – Impact
position P8 – Club shaft is parallel to ground AFTER impact
To give a quick view of what is happening around impact we have calculated snapshot values. These values are not “positions” in golf swing, but instead 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 Impact position.
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 Impact 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 absolute 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 body rotation during the backswing will also rotate the wrist relative to address.
The snapshot values in the tiles view measure the amount of absolute rotation before and after impact. For example the graph here demonstrates 52 degrees of rotation between P6 position and Impact and 66 degrees of rotation from impact to P8 position.
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.