Contents of Article
What is IMA?
Inertial Movement Analysis (IMA) is a set of metrics that measures athlete micro movements and direction regardless of unit orientation. Athlete movements can be quantified into low, medium and high intensity athlete movements zones that are used to construct profiles of athletes movements and to recognize biomechanical red flags.
IMA gives indoor and outdoor sports the ability to track:
- Acceleration count
- Deceleration count
- Asymmetrical loading
- Change of direction (COD) count - left and right
- Free running event count
- Free running total time
- Average stride rate
- Jump count
How is IMA applicable?
IMA allows the end user to collect and analyze acceleration and deceleration based data without the use of a GPS system. It is beneficial for Indoor sessions in which a user can't collect GPS data. It is also beneficial for breaking down movements into micro movements which can further be analyzed for performance insights.
How is IMA Calculated?
IMA uses an algorithm that takes into consideration data collected from both a tri-axial accelerometer and a tri-axial gyroscope to graphically evaluate the magnitude of every micro movement an athlete makes. This allows the user to track athlete performance without a GPS signal and at a higher sampling frequency (100 Hz in comparison to 10 Hz for GPS).
An advanced gravity filtering model is used to compensate for the application that gravity has on every object. This filter helps differentiate between athlete and device movements to improve the accuracy of the data. IMA movements are expressed in m/sec.
IMA is further dissected into incremental movements based on a clock based model. The clock represents 360 degrees which is divided into 12 segments of 30 degrees (i.e each hour on a clock represents 30 degrees and each 5 minutes tick represents 6 degrees). Each quarter of the clock is 90 degrees and represents one of the four micro movements:
- Acceleration (-45 to 0, 0 to 45 degrees)
- Deceleration (135 to 180, -180 to -135 degrees)
- Change of Direction - Left (-135 to -45 degrees)
- Change of Direction - Right (45 to 135 degrees)
The direction of the change of direction is determined by the direction of the applied force and the orientation of the athlete. For example, when an athlete plants their left foot to cut right, the direction of the applied force is to the right. This will register as a Change of Direction to the right.
How to set Bands for IMA
IMA Bands can be set by following the steps in our Bands article. Please select 'IMA Impact', 'IMA Intensity', 'IMA Jumps' as the parameter from the drop down menu.
IMA Parameter Definitions
For a list of IMA parameters, please see our OpenField Cloud Parameter Definitions article. The definitions can be found under the IMA section.