Table 3.

Change in translational and rotational head velocities due to H2G impacts in the HS age group

	ΔVR (m/s)	ΔωR (rad/s)	$\mathit{\alpha }$(°)	Δtwindow (s)
Mean	3.0	23.4	−47.6	0.06
SD	1.1	10.8	26.8	0.02
Range	1.5–4.9	10.1–43.3	−79.6 to 0.2	0.04–0.10

α (°), direction of head translational velocity vector with respect to the horizontal, (-) indicates the vector points below the horizontal; H2G, head-to-ground impact; HS, high school; Δω_R, change in resultant rotational velocity due to impact; Δt_window, impact interval; ΔV_R, change in resultant translational velocity due to impact.