The Motion Analysis tool offers 2 reference options for viewing acceleration data: local and global.
Global acceleration is the default setting, and makes sense for virtually all uses of the tool. However, we have included the local acceleration reference point as well. You have the option to toggle between local and global acceleration by clicking on the gear icon on the top right corner of the page.
Local vs. Global acceleration
Global acceleration is referenced to the pool, measuring the rate at which an athlete’s speed changes as they swim down the pool. This is the reference point that will make the most sense to virtually all users.
Local acceleration is referenced to the Triton unit itself, coming directly from the sensors within the unit and including a gravity component. We use this data to calculate global acceleration, however there is virtually no reason to utilize it when reviewing a motion analysis session.
Why use global acceleration
Global acceleration gives you acceleration in the directions you care about - with respect to the pool. It provides a more understandable, relevant frame of reference for measuring how much an athlete’s speed changes as they swim from one end of the pool to the other.
Learn more about the acceleration graph here.