Forward Lunge

Overview

The forward lunge is a fundamental movement assessment that evaluates an athlete’s ability to perform a stepping motion with proper form and stability. This movement is commonly used in athletic assessment and training as it provides valuable information about lower extremity strength, balance, and movement patterns.

Example image of a man doing a forward lunge

Instructions

Stand with feet hip-width apart in a neutral stance. Step forward with one leg, lowering the back knee toward the ground while keeping the trunk upright. Drop down as far as possible, being careful to not slam your rear knee into the ground. Push back through the front foot to return to the starting position. Perform at a natural, controlled pace without pausing at the bottom.

Dimensions

Required inputs for processing:

Footedness: [‘right’, ‘left’] — indicates the lead (stepping) leg

Output Variables

Generic Outputs

Every capture includes session metadata, standard joint angle/velocity time series, and 3D keypoint positions common to all movements. See Generic Outputs for the full list.

Events

Metric	Description	Column Name
Initiation	The start of the lunge when the athlete begins stepping forward	`lunge_forward_initiation_frame`
Bottom	The instant of maximum lunge depth (lowest pelvis position)	`lunge_forward_bottom_frame`
End	The end of the movement when the athlete returns to standing	`lunge_forward_end_frame`

Phases

Phase	Start	End
Eccentric (Descent)	Initiation	Bottom
Concentric (Ascent)	Bottom	End

Knee Metrics

Metric	Units	Description	Column Name
Right Valgus Bottom	meters	Right knee medial displacement at bottom position	`lunge_forward_right_valgus_bottom`
Left Valgus Bottom	meters	Left knee medial displacement at bottom position	`lunge_forward_left_valgus_bottom`

Movement Strategy Metrics

Metric	Units	Description	Column Name
Right Eccentric Hip-Knee Dominance	ratio	Right lead leg hip-knee dominance during descent (0=hip, 1=knee)	`lunge_forward_right_eccentric_hip_knee_dominance`
Left Eccentric Hip-Knee Dominance	ratio	Left lead leg hip-knee dominance during descent (0=hip, 1=knee)	`lunge_forward_left_eccentric_hip_knee_dominance`
Right Concentric Hip-Knee Dominance	ratio	Right lead leg hip-knee dominance during ascent (0=hip, 1=knee)	`lunge_forward_right_concentric_hip_knee_dominance`
Left Concentric Hip-Knee Dominance	ratio	Left lead leg hip-knee dominance during ascent (0=hip, 1=knee)	`lunge_forward_left_concentric_hip_knee_dominance`

Trunk and Joint Angle Metrics

Metric	Units	Description	Column Name
Max Right Trunk Lean	degrees	Maximum rightward lateral trunk lean during lunge	`lunge_forward_max_right_trunk_lean`
Max Left Trunk Lean	degrees	Maximum leftward lateral trunk lean during lunge	`lunge_forward_max_left_trunk_lean`
Max Right Hip Flexion Angle	degrees	Maximum right hip flexion angle during lunge	`lunge_forward_max_right_hip_flexion_angle`
Max Left Hip Flexion Angle	degrees	Maximum left hip flexion angle during lunge	`lunge_forward_max_left_hip_flexion_angle`
Max Right Knee Flexion Angle	degrees	Maximum right knee flexion angle during lunge	`lunge_forward_max_right_knee_flexion_angle`
Max Left Knee Flexion Angle	degrees	Maximum left knee flexion angle during lunge	`lunge_forward_max_left_knee_flexion_angle`
Max Right Ankle Flexion Angle	degrees	Maximum right ankle dorsiflexion during lunge	`lunge_forward_max_right_ankle_flexion_angle`
Max Left Ankle Flexion Angle	degrees	Maximum left ankle dorsiflexion during lunge	`lunge_forward_max_left_ankle_flexion_angle`

Distance Metrics

Metric	Units	Description	Column Name
Lunge Depth	meters	Vertical pelvis displacement from baseline to bottom	`lunge_forward_lunge_depth`
Stance Length	meters	Anterior–posterior distance between feet at bottom	`lunge_forward_stance_length`
Stance Width	meters	Medial–lateral distance between feet at bottom	`lunge_forward_stance_width`

Notes

Kinematic data typically captured at 60 Hz for lunging
Lead leg metrics (valgus, hip-knee dominance) are reported for the stepping leg only; the non-lead side is set to NaN
Trunk and joint angle metrics are computed over the full lunge window (Initiation to End)
Stance dimensions are measured at the Bottom event, normalized to pelvis orientation

Get Started

Resources

Biomechanics

Overview

Instructions

Dimensions

Output Variables

Generic Outputs

Events

Phases

Knee Metrics

Movement Strategy Metrics

Trunk and Joint Angle Metrics

Distance Metrics

Notes

​Overview

​Instructions

​Dimensions

​Output Variables

​Generic Outputs

​Events

​Phases

​Knee Metrics

​Movement Strategy Metrics

​Trunk and Joint Angle Metrics

​Distance Metrics

​Notes

Overview

Instructions

Dimensions

Output Variables

Generic Outputs

Events

Phases

Knee Metrics

Movement Strategy Metrics

Trunk and Joint Angle Metrics

Distance Metrics

Notes