Research Article

Head Impact Exposure in Junior and Adult Australian Football Players

Table 1

Impacts to the head greater than 10 for total impacts recorded, impacts by total, junior, and senior level teams and by forwards midfielders and defenders for each level of participation in an amateur Australian Football League team over a season of matches. Data are presented as median [interquartile range] and 95th percentile for total impacts, impacts per player position group, impact duration (ms), resultant linear and rotational acceleration, head impact telemetry severity profile, and risk weighted exposure combined probability.

Total
impacts 
n =
Per player
per match
season
Per player
per match
Impact
duration
(ms)
PLA ()PRA (rad/s2)
Mean ± SDMean ± SDMean ± SDMedian [IQR]95%Median [IQR]95%Median [IQR]95%Median [IQR]95%

Total
 Combined1,60960 ± 368 ± 810.9 ± 7.915.3 [11.9–23.3]45.82,729.8 [1,680.0–4,784.3]9,592.915.5 [13.2–20.8]41.70.0008 [0.0003–0.0060]0.9874
 Junior86162 ± 397 ± 915.1 [11.9–22.2]45.72,741.7 [1,712.8–4,648.4]9,644.515.3 [12.6–21.2]46.80.0008 [0.0003–0.0052]0.3969
 Senior74858 ± 358 ± 715.7 [11.9–24.2]46.82,757.4 [1,652.6–4,915.7]9,556.115.4 [13.0–21.2]39.00.0008 [0.0003–0.0067]0.3862

Junior
 Forwards57 ± 177 ± 6 [11.7–21.6]40.52,493.1 [1,511.3–4,760.5]9,427.415.4 [11.7–26.1]98.00.0006 [0.0002–0.0061]0.3484
 Midfielder71 ± 608 ± 12 [12.0–22.5]47.32,676.3 [1,718.5–4,808.0]10,672.915.2 [12.7–20.4]46.80.0007 [0.0003–0.0063]0.6233
 Defender55 ± 308 ± 5 [11.9–22.2]39.52,815.1 [1,848.2–4,433.0]8,406.2 [12.9–21.6]42.70.0008 [0.0003–0.0040]0.2035

Senior
 Forwards59 ± 279 ± 7 [11.7–24.3]45.22,701.0 [1,623.5–5,235.5]9,766.714.2 [11.6–22.1]46.00.0008 [0.0003–0.0101]0.4802
 Midfielder76 ± 5411 ± 11 [12.5–26.5]52.82,963.1 [1,744.6–5,068.2]9,617.215.1 [13.1–21.2]43.10.0010 [0.0003–0.0082]0.4660
 Defender41 ± 128 ± 7 [11.9–21.4]43.12,519.2 [1,569.7–4,560.7]8,599.6 [13.6–20.6]37.50.0006 [0.0003–0.0042]0.2701

[IQR] = interquartile (25th to 75th) percentile; 95% = 95th percentile; PLA () = peak linear acceleration in gravitational force (); PRA (rad/s2) = peak rotational acceleration in radians/second2; = Head Impact Telemetry Severity Profile; = Risk Weighted Exposure Combined Probability; significant difference compared to forward; midfielder; defender; junior; senior.