Table 4.

Outcome measures extracted from wearable technology within reviewed studies

Outcome	Definition	References
Spatiotemporal
Ground contact time/stance time n = 49	The time between initial foot contact and toe-off for the same foot	[24, 27–29, 33, 37, 40, 42, 49–51, 53–55, 59, 63, 66, 67, 71, 75, 77, 79, 80, 85–87, 89, 90, 92, 95, 96, 99, 101, 105, 107, 110, 120, 123–125, 128, 134, 135, 139, 140, 143, 144, 150, 151]
Cadence, step/stride frequency/rate n = 36	The number of steps or strides taken during a given time	[20, 21, 28, 29, 31, 33–35, 51, 59, 70, 72, 77, 80, 82, 87, 90, 91, 93, 101, 102, 105, 106, 108, 110, 111, 117, 119, 120, 125, 128, 131, 132, 135, 139, 147]
Step/stride length n = 29	The distance between successive points of initial contact of the same foot (stride) or opposite foot (step)	[20, 33–35, 42, 49, 50, 54, 59, 61, 70, 80, 85, 87, 90–92, 98, 100–102, 105, 106, 108, 119, 128, 132, 139, 143]
Step/stride time n = 16	The time between two consecutive heel strikes of the same foot (stride) or opposite foot (step)	[27, 34, 42, 48, 59, 72, 75, 85, 90, 92, 100, 101, 106, 107, 128, 143, 144]
Foot strike pattern/strike index/foot strike angle n = 15	The moment, way or angle when the foot first makes contact with the ground	[21, 26, 33, 40, 59, 68, 69, 80, 84, 87–89, 93, 116, 144]
Flight time n = 15	The time between toe-off from one foot to initial contact of the other foot	[50, 77, 87, 89, 90, 92, 95, 96, 101, 105, 110, 124, 128, 139, 144]
Acceleration* n = 15	The rate of change of the velocity of any segment (excluding tibia)	[19, 35, 38, 62, 64, 73, 74, 78, 93, 97, 116, 119, 121, 129, 130]
Speed/velocity n = 15	The rate of change of position (directional)	[33, 42, 61, 79, 82, 85, 90–92, 98, 100, 102, 104, 106, 129]
Gait events n = 11	Identification of any of the key gait events, e.g. heel strike, toe-off, mid-stance	[27, 36, 59, 63, 71, 78, 92, 98, 130, 144, 150]
Vertical oscillation n = 9	The amount that the torso or COM moves vertically with each step or stride	[20, 21, 28, 29, 59, 90, 93, 134, 139]
Swing time n = 7	The period during which the foot is not in contact with the ground	[27, 39, 59, 89, 124, 125, 139]
Cycle time n = 4	The time taken to complete a single gait cycle (can be measured from any gait event to the same subsequent event on the same foot)	[46, 49, 54, 89]
Acceleration of centre of mass n = 4	The rate of change of the velocity of the centre of mass	[30, 32, 72, 76]
Step/stride height/foot clearance n = 2	The vertical distance obtained during the swing phase	[82, 98]
Symmetry n = 2	Any measure of imbalance between the right and left leg	[133, 137]
Kinematic
Ankle/foot kinematics n = 19	Description of ankle or foot movement in any of the three cardinal planes: sagittal, frontal, transverse planes, without consideration for forces	[19, 20, 33, 43, 49, 50, 54, 73, 80, 85, 87, 89, 94, 103, 105, 107–109, 122]
Hip/pelvis kinematics n = 11	Description of hip or pelvis movement in any of the three cardinal planes: sagittal, frontal, transverse planes, without consideration for forces	[19, 20, 28, 29, 36, 73, 103, 105, 106, 108, 109]
Knee kinematics n = 10	Description of knee movement in any of the three cardinal planes: sagittal, frontal, transverse planes, without consideration for forces	[19–21, 73, 97, 103, 105, 106, 108, 109]
Trunk kinematics n = 3	Description of trunk movement in any of the three cardinal planes: sagittal, frontal, transverse planes, without consideration for forces	[21, 105, 108]
Kinetic
Derivatives of tibial acceleration n = 28	Acceleration of the tibia, including peak positive acceleration, gradient, slope, magnitude, loading rate	[19, 34, 35, 41, 42, 44, 46, 48, 52, 53, 56–58, 60, 61, 64, 74, 111–115, 118, 119, 123, 131, 137, 138]
Plantar pressure n = 17	Pressure = force/area, where force describes the vGRF exerted and area describes the surface area of the foot that is in contact with the ground during running	[25, 37, 40, 45, 47, 53, 55, 65–69, 143, 145, 146, 148, 151]
Ground reaction force n = 13	The force exerted by the ground on a body in contact with it	[24, 59, 87, 95–97, 123, 130, 136, 139–142]
Contact area n = 12	Area of contact for each or any plantar region	[37, 47, 55, 65–69, 145, 146, 148, 151]
Pressure or force–time integral n = 10	The cumulative effect of pressure or force during a step cycle (area under the pressure–time or force–time curve)	[40, 47, 65, 66, 68, 69, 124, 125, 145, 150]
Impact n = 9	The vertical force observed during the initial contact	[23, 33, 49–51, 54, 80, 93, 147]
Force n = 8	Including rate and magnitude of force development	[39, 40, 47, 90, 104, 124, 149, 150]
Impulse n = 8	A measure of the force applied for a specific time and distance	[34, 45, 47, 123, 124, 140, 142, 149]
Braking n = 7	The force applied to the body that causes it to slow down	[28, 29, 33, 49, 50, 54, 93]
Load/loading rate n = 5	The speed at which you apply forces to the body	[45, 97, 123, 143, 149]
Centre of pressure n = 2	The point of application of the GRF	[125, 141]

Note: Some studies fall under more than one category

GRF ground reaction force, vGRF vertical ground reaction force