Golf Swing Analysis with IMUs: Noraxon MR4 Workflow

Understanding a golfer’s swing goes beyond just clubhead speed. The ability to measure the underlying biomechanics provides critical insight into coordination, energy transfer, and postural stability. Noraxon’s myoRESEARCH (MR4) software includes a dedicated, automated golf swing analysis workflow that utilizes just four Inertial Measurement Units (IMUs) to deliver objective feedback for performance training. The 4-Sensor IMU Setup This workflow simplifies biomechanical testing in the field, requiring only four Ultium Motion IMU sensors placed on the:. 1. Pelvis, 2. Upper Spine, 3. Lead Upper Arm (Left for right-handed golfers), 4. Lead Hand (Left for right-handed golfers). Automated Swing Detection & Calibration. Utilizing the Kinetic Chain Application , the MR4 software automatically detects the critical phases of the swing: Backswing, Downswing, and Follow-through. Using the advanced Multipose Calibration routine, the setup is incredibly fast. The system automatically accounts for multiple swings in a single recording and manages sensor drift perfectly by allowing the athlete to briefly pause in a reference pose between high-velocity swings. Kinematic Sequencing: The Flow of Energy. The foundation of this analysis is the Kinematic Sequence Plot. In an efficient, powerful golf swing, energy transfers in a strict proximal-to-distal sequence:. Pelvis → Trunk (Upper Spine) → Lead Arm → Hand/Club., The Whip Effect: Each segment must reach its peak angular velocity slightly after the previous segment begins to decelerate., Identifying Breakdowns: If a segment peaks too early or out of order (e.g., the arms firing before the trunk), energy transfer is lost, reducing clubhead speed and increasing compensatory strain on the body. MR4 provides precise timing and peak velocity data for each of these segments. X-Factor & Postural Separation The report also generates an automated X-Factor plot, visualizing the rotational separation between the pelvis and the trunk. X-Factor Stretch: As the downswing begins, an efficient golfer's pelvis will start rotating toward the target before the trunk has finished its backswing. This creates a rapid pre-stretch (the X-Factor stretch), storing elastic energy in the core musculature that ultimately amplifies the speed of the trunk rotation., The MR4 plot provides clear visualization of this crucial separation angle from setup through impact. Note: Automated Golf Swing Analysis is available in MR version 4.2026.1 and newer.