{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,5]],"date-time":"2026-05-05T15:15:09Z","timestamp":1777994109419,"version":"3.51.4"},"reference-count":51,"publisher":"BMJ","issue":"10","funder":[{"name":"Rugby Football League"}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["Br J Sports Med"],"accepted":{"date-parts":[[2026,3,22]]},"published-print":{"date-parts":[[2026,5]]},"abstract":"<jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>To quantify concussion and head acceleration event (HAE) probability in rugby league tackles by tackle height and role and simulate seasonal counts across different tackle height distributions.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Using a prospective cohort study, data reflecting clinically diagnosed concussions (n=56) and HAEs (n=4632; measured via instrumented mouthguards from 23\u2009081 tackles in 92 players) were collected during the 2023\u2009men\u2019s Super League season. Video analysis captured tackle heights for all concussive and accelerometer-measured tackles. Role-specific probabilities were calculated using cumulative link mixed models. Monte Carlo simulation quantified concussions and HAEs across the current tackle-height distribution and three lower tackle-height distributions (weighted redistribution (increased torso tackles), even redistribution (increased torso and lower body tackles) and observed law trial distribution).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Ball-carriers experienced the highest concussion and HAE risk from head\/neck contact compared with other tackle heights (eg, HAE \u226525\u2009g; 2.7% vs 0.4%\u20131.1%), while tackler risk was similar. The number of ball-carrier concussions (16 vs 8\u20139) and HAEs (\u226525\u2009g; 830 vs 357\u2013556) decreased with all lower tackle-height distributions. For tacklers, the only meaningful change was an increase in HAEs following the even redistribution of a lower tackle height (\u226525\u2009g; 2081 vs 2204). When considering both roles together, only even and weighted lower tackle-height redistributions reduced the total number of lower-to-moderate magnitude HAEs, with no meaningful differences observed for concussions or higher magnitude (\u226555\u2009g) HAEs.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Lowering the tackle height creates a protection paradox, benefiting ball-carriers, while potentially maintaining or increasing the risk for tacklers. Simulated findings may inform policy changes by estimating outcomes and allowing evaluation prior to implementation.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bjsports-2025-110677","type":"journal-article","created":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T17:20:23Z","timestamp":1776187223000},"page":"706-713","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Tackle higher or lower? Simulation to evaluate how changing the tackle height would impact the number of concussions and head acceleration events in men\u2019s professional rugby league"],"prefix":"10.1136","volume":"60","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6518-1389","authenticated-orcid":false,"given":"Cameron","family":"Owen","sequence":"first","affiliation":[{"name":"Carnegie Applied Rugby Research (CARR) Centre, Leeds Beckett University, Leeds, UK"},{"name":"England Performance Unit, Rugby Football League, Manchester, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5398-4416","authenticated-orcid":false,"given":"James","family":"Tooby","sequence":"additional","affiliation":[{"name":"Carnegie Applied Rugby Research (CARR) Centre, Leeds Beckett University, Leeds, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thomas","family":"Sawczuk","sequence":"additional","affiliation":[{"name":"Carnegie Applied Rugby Research (CARR) 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