​
Tennis: Overhand Serve

​
Overview

​
Events

MetricData TypeDescription
InitiationIntthe start of the tennis serve
Ball ReleaseIntthe estimated timing of ball toss release
Low ArmIntthe low point of the dominant arm prior to ball contact
Max Shoulder ERIntthe instant of maximum shoulder external rotation between ball release and apex
ApexIntmaximum height of the dominant-side wrist joint center during the serve
TerminationIntend of the tennis serve

​
Phases and Stages of the Tennis Serve

PhaseStageStartEndEvent or Phase
PreparationStartInitiationInitiationEvent
PreparationReleaseInitiationBall ReleasePhase
PreparationLoadingBall ReleaseLow ArmPhase
PreparationCockingLow ArmMax Sho ERPhase
AccelerationAccelerationMax Sho ERBall ContactPhase
AccelerationContact BallContact BallContactEvent
Follow ThruDeccelerationBall ContactTerminationPhase
Follow ThruFinishTerminationTerminationEvent

​
Discrete Metrics

MetricData TypeUnitsDescription
HandednessStringN/AHandedness of the athlete.
Stance PositionStringN/AClassification of serve stance position. Options are ‘platform’ or ‘pinpoint’
Loading Phase Max Knee Flexion Front LegFloatdegreesMaximum amount of front leg knee flexion during the loading phase of the serve
Loading Phase Max Knee Flexion Back LegFloatdegreesMaximum amount of back leg knee flexion during the loading phase of the serve
Loading Phase Trunk TiltFloatdegreesMaximum amount of trunk side-side tilt towards the rear during the loading phase of the serve
Loading Phase Pelvis TiltFloatdegreesMaximum amount of pelvis side-side tilt towards the rear during the loading phase of the serve
Loading Phase Shoulder Hip SeparationFloatdegreesMaximum difference in rotation of the shoulders and hips during the loading phase of the serve
Loading Phase Ball Release AngleFloatdegreesAngle between wrist and shoulders at the instance of ball release. 90 degrees would be exactly in front of the non-dominant shoulder, 180 degrees would be sideways completely horizontal.
Cocking Phase Max Shoulder External RotationFloatdegreesMaximum amount of shoulder external rotation during the cocking phase of the serve
Cocking Phase Shoulder HyperangulationFloatdegreesMaximum amount of shoulder horizontal abduction during the cocking phase of the serve
Acceleration Phase Max Knee Extension Velocity Front LegFloatdegrees/secondMaximum knee extension velocity of the front leg during the acceleration phase of the serve
Acceleration Phase Max Knee Extension Velocity Back LegFloatdegrees/secondMaximum knee extension velocity of the back leg during the acceleration phase of the serve
Contact Phase Elbow FlexionFloatdegreesAmount of elbow flexion at apex
Contact Phase Shoulder AbductionFloatdegreesAmount of shoulder abduction at apex
Contact Phase X FactorFloatdegreesAngle between the shoulders to hips in the transverse plane (twisting) at apex
Contact Phase Trunk TiltFloatdegreesDegrees of side-side trunk tilt at apex
Peak Torso Forward Angular VelocityFloatdegrees/secondPeak forward angular velocity of the torso segment in the serve direction
Peak Upper Arm Forward Angular VelocityFloatdegrees/secondPeak forward angular velocity of the upper arm segment in the serve direction
Peak Forearm Forward Angular VelocityFloatdegrees/secondPeak forward angular velocity of the forearm segment in the serve direction
Kinematic SequenceStringN/ASequence of peak forward angular velocities. Optimal sequence is ‘torso-upper_arm-forearm’

​
Detailed Documentation

​
Events

::: upliftbiomch.events.tennis_events

​
Metrics

::: upliftbiomch.metrics.tennis_metrics

​
Notes

  • All angular measurements follow ISB conventions
  • Kinematic data typically captured at 240Hz for Tennis Overhand Serve