You can actually wear these swing vests during a round, but there is a catch
A 3D Smart Shirt that analyzes and trains your golf swing can be worn during play in 2026, but there is one slight catch.
The shirt, which is more like a vest made to be worn under a golf shirt, is made by a company called 4D Motion, and it features inertial sensors in the torso and pelvis area to analyze everything from spine angle to pelvis bend. The sensors are able to communicate this information back to an app on your phone or on an Apple Watch.
A perfect practice tool, the vest is now permitted during actual competition under the Rules of Golf, though you cannot access the information the vest provides until after the round is over. If such biomechanical analysis, kinematic sequence data or other information is accessed during play, the player could be in breach of Rule 4.3a, which covers all types of equipment that a player may use during a round and how they can use it. Similar to Arccoss sensors, players would not be able to access any real-time feedback, such as audio or visual cues, from the vest during play.
After the round, however, the player can access every bit of data from the vest, which tracks every single swing. You'll be able to see exactly what went wrong when you pulled that tee shot out of bounds on the third hole, or exactly what went right when you were under pressure on the 18th tee.
Were a player to access the information during play, they'd receive a two-stroke penalty for the first breach. A second breach would result in disqualification.