Abstract
Objective
To compare incidence rates (IR) of bodychecking (BC), head contacts (HC), and suspected injuries across Canadian adolescent ice sports (girls' ice hockey, ringette, boys’ ice hockey, and para ice hockey) via a cross-sectional video-analysis study.
Methods
Video-recordings were obtained from 144 games played between 2008 and 2022 (2021–2022 for ringette, girls', and para ice hockey; 2008–2021 for boys’ ice hockey) in Canadian arenas. Video-recordings were analyzed using Dartfish video-analysis software to compare all ice sports. Univariate Poisson regression analyses (adjusted for cluster by team, offset by game-minutes) were used to estimate BC, HC, and suspected injury IRs and incidence rate ratios (IRRs) to compare rates across sports. Proportions of BCs and direct HC (HC1) penalized were reported.
Results
Compared with non-elite non-BC boys' ice hockey, there were significantly higher rates of BC in non-BC girls' ice hockey (IRR = 2.67, 95%CI: 1.82–3.90), non-BC ringette (IRR = 5.72, 95%CI: 4.03–8.11), and BC-permitted boys' ice hockey (IRRelite = 9.15, 95%CI: 6.63–12.64; IRRnon-elite = 5.89, 95%CI: 4.07–8.53). HC rates were significantly higher for non-BC girls' ice hockey (IRR = 2.76, 95%CI: 2.05–3.71), non-BC ringette (IRR = 4.06, 95%CI: 3.02–5.46), and BC-permitted boys’ ice hockey (IRRelite = 3.18, 95%CI: 2.41–4.18; IRRnon-elite = 2.64, 95%CI: 1.92–3.62). Para ice hockey did not significantly differ for both BC and HC. The proportions of player-to-player HCs penalized ranged from 0 to 20% across sports.
Conclusions
The high rates of BC are concerning in ice sports prohibiting BC (ringette and girls’ ice hockey). The low proportion of penalized HCs across all ice sports suggests a need for improved policy enforcement to prevent injuries and concussions.
Keywords: Ringette, Ice hockey, para ice hockey, Injury, Concussion, Video analysis
Key points.
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This study provides the first multi-sport comparison of bodychecking, head contact, and suspected injury and concussion events across Canadian adolescent ice sports using a consistent video-analysis protocol.
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Substantial differences in bodychecking and head contact rates were observed between sports, with ringette and boys' ice hockey showing the highest frequencies and para ice hockey the lowest.
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Penalty rates for illegal head contacts were low across all four sports, highlighting a gap between policy intent and on-ice implementation and identifying opportunities for strengthening enforcement and education to support injury prevention.
1. Introduction
Popular ice sports amongst Canadian adolescents include ice hockey, para ice hockey, and ringette [1,2]. Although these sports have similar rules/objectives (e.g., skating, team structure), they do have differences in rules and equipment [3,4]. Para ice hockey is a seated adaptation of stand-up ice hockey, where athletes with disabilities compete sitting in sleds fitted with a central blade and use two sticks with metal picks for propulsion [5]. Ringette is a stand-up team ice sport in which players use a straight, bladeless stick to pass, carry, and shoot a hollow rubber ring, rather than a using a bladed hockey stick and puck [3].
Participation in these team ice sports is widespread. From a 2022 parent survey of physical activity and sport participation, among the top 15 sports reported by Canadian children and youth, hockey and ringette ranked third, reported by 16% of sport participants, behind soccer and basketball [6]. Hockey Canada reported 589,012 registered athletes in the 2023-24 season, including 108,313 girls and women and 932 para ice hockey players (179 girl and woman para ice hockey players) [2]. During the 2024-25 season, Ringette Canada reported 33,657 registered athletes, with 31,941 identifying as girls or women, 1,333 as boys or men, and 240 as non-binary [1]. These numbers demonstrate that these team ice sports are among the most widely played organized sports for Canadian girls and women, highlighting the importance of gaining a better understanding of the injury and concussion risk. Although this study focuses on Canadian data, these ice sports are played internationally (ice hockey: 70 countries [7]; ringette: 11 countries [8]) under similar rules, making the findings relevant to broader injury prevention contexts.
Injury and concussion prevention is a priority in adolescent ice sports because previous surveillance and video-analysis studies have reported substantial rates of bodychecking (BC; high intensity trunk physical contact), head contacts (HCs; both direct player-to-head contacts and indirect head-to-boards/glass/ice), and suspected injuries [[9], [10], [11], [12], [13], [14]]. Although Canadian policies prohibit BC in ringette and girls' ice hockey and penalize direct HCs in all ice sports, these rules are not consistently enforced in practice [15]. A few video-analysis studies have independently examined injury mechanisms in each sport, but no prior study has directly compared these rates across all team ice sports using standardized video-analysis methods [[9], [10], [11], [12], [13], [14]]. Comparing BC, HC, suspected injuries and concussions, and penalty enforcement across these ice sports is essential for developing holistic, equitable injury prevention strategies. Therefore, the objective of this study was to compare incidence rates of BC, HC, suspected injuries and concussions, and the proportion of penalized direct HCs across Canadian adolescent boys' and girls’ ice hockey, para ice hockey, and ringette using standardized video-analysis methods.
2. Materials & methods
2.1. Study design & setting
This cross-sectional video-analysis study included 144 games from Canadian adolescent and para ice sports spanning multiple seasons (Table 1). Although footage originated from different years, all videos were analyzed using identical operational definitions and procedures [16], ensuring comparability across sports and time periods. Subsets of these data have been reported previously in single-sport analyses using similar video-analysis methods [[9], [10], [11], [12], [13], [14]].
Table 1.
Game footage characteristics by sport, age group, and competition level.
| Sport/cohort | Games (n) | Seasons | Bodychecking permitted | Participants | Age group(s) | Competition level |
|---|---|---|---|---|---|---|
| Boys' ice hockey | 26 | 2015–2017 | No | Boys | Under-15 & under-18 | Non-elite (divisions 3–6) |
| 26 | 2014–2017 | Yes | Boys | Under-15 & under-18 | Non-elite (divisions 3–6) | |
| 35 | 2008–2009, 2013–2014, 2020–2021 | Yes | Boys | Under-15 | Elite (AA) | |
| Girls' ice hockey | 8 | 2021–2022 | No | Girls | Under-15 | Elite (AA) |
| Ringette | 39 | 2021–2022 | No | Mixed (mainly girls) | Under-16 & under-19 | Elite (AA and A) |
| Para ice hockey | 10 | 2021–2022 | Yes | Mixed | Not defined (adolescent and adult) | Elite (Intermediate C) |
Note: In Canada, elite (AA) represents the highest competitive level within an age group, while non-elite divisions (e.g., divisions 3–6) represent community-based competitive levels below elite.
2.2. Video footage collection
Games were recorded in Canadian arenas using a high-definition Panasonic Full HD HC-V770 video camera mounted on a tripod. Footage was recorded at 1080p resolution and 60 frames per second. All study footage was recorded using this camera model and recording setting. Footage was research-recorded rather than broadcast footage. Cameras were located at an elevated position near centre ice whenever possible, with the next location being at the corner at ice level when the ideal position was not available (e.g., no/low stands, netting). Camera operators were trained to maintain the play in the frame, following the puck/ring carriers, display the scoreboard during stoppages, and capture referee signals to document penalties. All video-recordings were stored on a secure, access-restricted university server (SharePoint) and were not publicly accessible.
2.3. Outcome measures
Game footage was analyzed using Dartfish v10.0 [17], which allows for frame-by-frame tagging of player-to-player physical contacts (PCs) through a custom-built coding panel. Trained video-analysts with experience in each sport (e.g., player, coach) completed inter-rater reliability (≥90%) with a gold standard assessor in each sport on all contact metrics prior to independent coding. Player-to-player PCs were coded using validated operational definitions of trunk contact intensity, HC type, and sled contact configuration (for para ice hockey only) (Table 2). Example videos of each contact type were used alongside the definitions to support consistent interpretation and coding. Head contacts were categorized according to the source of the visible external contact to the head: player-to-head contacts (direct; HC1) or environment-to-head (indirect; HC2). Indirect inertial head-loading events without visible external contact to the head were not coded in this study.
Table 2.
Trunk, head, sled, and other contact definitions used for video analysis in adolescent ice sports [9,10,11,12,13,14].
| Definition | |
|---|---|
| Trunk physical contacts | |
| Level 1 | Very light contact between two stationary players. |
| Level 2 | Light contact between two players moving in the same relative direction. |
| Level 3 | Moderate contact between two players moving in the same relative direction. |
| aLevel 4 | Heavy contact, with one player forcefully exerting one's body into the opposing player, usually moving in the opposite direction. Minimum requirement of a body contact penalty. |
| aLevel 5 | Excessive, deliberate contact from one player with the intention beyond impeding the progress of the opponent, moving in the opposite direction. |
| Head contacts (HC) | |
| aDirect head contact (HC1) | Direct contact to the head by the opposing player. |
| Indirect head contact (HC2) | Indirect contact to the head via the boards, glass, net, or ice surface. |
| bSled physical contacts | |
| aT-bone | The nose of one player's sled contacts the side of another player's sled at a 90-degree angle. |
| Angled | The nose of one player's sled contacts the side of another player's sled at any non-90-degree angle. |
| Nose-to-Nose | Player sleds contact each other head on. |
| Nose-to-Back | Contact player initiates contact with the front of their sled to the back of the receiving player's sled. |
| Other physical contacts | |
| Limb | Contact using one or both upper extremities, such as pushing, punching, or holding. |
| Stick | Contact to the body using the stick, such as slashing, hooking, or cross checking. |
Indicates contacts that should always be penalized by referees in leagues that don't allow body checking, head contacts, or t-bone sled contacts.
Indicates contacts that were only used for para ice hockey.
No linked medical injury database was available for this cross-sport video-analysis study. Therefore, injury outcomes were classified as video-suspected injuries and suspected concussions based on observable signs. Suspected injuries were identified when one or more of the following validated criteria were observed: referee stopped play for injury, player remained on the ice for longer than 15 seconds after contact, and the player appeared to be in pain [18]. These video-based definitions have been validated previously in youth and non-elite sport settings, including studies using trained non-clinician coders [19]. Suspected concussions were defined as events meeting the suspected injury criteria plus at least one observable sign consistent with expert consensus (e.g., lying motionless, dazed, slow to get up, clutching at head) [20].
2.4. Data analysis
Following video coding, tagged event-level data were exported from Dartfish and merged with game-level information, including sport/cohort, team, game duration, BC policy, and competition level. Data were checked for duplicate, missing, and implausible tags before being imported into Stata for analysis. All data was analyzed using STATA version 17.1 statistical software [21]. Univariate Poisson regression analyses (adjusted for cluster by team and offset by game-minutes) were used to estimate incidence rates (IRs; expressed as the number of contacts per 100 game-minutes with 95% confidence intervals [CIs]) and incidence rate ratios (IRRs with 95% CIs) by sport and BC policy. Non-elite non-BC boys’ ice hockey served as the reference group for these comparisons. Descriptive statistics were used to summarize the proportion of penalized illegal HCs.
To assess the potential influence of temporal differences in gameplay, a sensitivity analysis was conducted excluding boys’ elite ice hockey games from the 2008-09 season. IRs and IRRs were not significantly different when compared to the main analyses, and the overall pattern of results did not change, therefore, all years were retained in the final analyses.
2.5. Data management and ethics
All coded data and video files were stored on secure university servers. No player-identifiable information was collected, and analyses were limited to observable on-ice behaviour. Ethical approval for this study was obtained from the University of Calgary Conjoint Health Research Ethics Board (CHREB) (Ethics ID: REB21-0968).
3. Results
Numbers of games, game-minutes, and outcome counts (i.e., number of bodychecks, head contacts, suspected injuries, etc.) are provided in Table 3.
Table 3.
Total game-minutes, bodychecks, head contacts, and suspected injuries across adolescent ice sports.
| Sport | Games (n) | Game-minutes | Bodychecks (n) | Total head contacts (n) | Direct head contacts (n) | Indirect head contacts (n) | All suspected injuries (n) | Suspected non-concussion injuries (n) | Suspected concussion injuries (n) |
|---|---|---|---|---|---|---|---|---|---|
| Boys' ice hockey (non elite non-BC) | 26 | 1170 | 71 | 110 | 101 | 9 | 7 | 3 | 4 |
| Girls' ice hockey (elite non-BC) | 8 | 482 | 78 | 125 | 87 | 38 | 6 | 3 | 3 |
| Ringette (elite non-BC) | 39 | 1629 | 565 | 622 | 447 | 175 | 50 | 26 | 24 |
| Para ice hockey (elite BC) | 10 | 360 | 33 | 48 | 43 | 5 | 2 | 1 | 1 |
| Boys' ice hockey (non elite BC) | 26 | 1170 | 418 | 290 | 290 | 0 | 13 | 8 | 5 |
| Boys' ice hockey (elite BC) | 35 | 1899 | 1055 | 567 | 378 | 189 | 26 | 15 | 11 |
Note: All suspected injuries includes both suspected non-concussions and suspected concussions.
3.1. Bodychecking
BC incidence differed significantly across sports (Table 4). Compared with boys' non-BC ice hockey, rates were significantly higher in girls' ice hockey, ringette and BC-permitted boys' ice hockey. Both elite and non-elite BC-permitted boys' ice hockey demonstrated the highest rates, followed by ringette and girls’ ice hockey, despite BC being prohibited in the latter two sports. Para ice hockey did not statistically differ from the reference group.
Table 4.
Incidence rates (IRs) per 100 game-minutes and incidence rate ratios (IRRs) for bodychecking (BC) across adolescent ice sports. Boys’ non-bodychecking (non-BC) ice hockey served as the reference group.
| Sport | Bodychecking (BC) |
|
|---|---|---|
| IR/100 game-minutes (95% CI) | IRR (95% CI) | |
|
Boys' ice hockey (Non elite non-BC) |
6.07 (4.51–8.16) | (Reference) |
|
Girls' ice hockey (Elite non-BC) |
16.18 (12.46–21.00) | 2.67 (1.82–3.90)∗ |
|
Ringette (Elite non-BC) |
34.68 (28.58–42.09) | 5.72 (4.03–8.11)∗ |
|
Para ice hockey (Elite BC) |
9.17 (5.13–16.39) | 1.51 (0.81–2.82) |
|
Boys' ice hockey (Non elite BC) |
35.73 (28.34–45.03) | 5.89 (4.07–8.53)∗ |
|
Boys' ice hockey (Elite BC) |
55.56 (48.40–63.76) | 9.15 (6.63–12.64)∗ |
Notes: ∗Indicates a statistically significant difference (95% CI does not include 1) compared with boys' non-BC ice hockey.
3.2. Head contacts
HC incidence also differed significantly across sports (Table 5). Compared with boys' non-BC ice hockey, girls' ice hockey, ringette, and both BC-permitted boys' ice hockey divisions showed significantly higher total HC rates. Para ice hockey did not differ statistically from the reference group. When stratified by HC type, all sports except para ice hockey demonstrated significantly higher HC1 rates than the reference group. HC2 rates were significantly higher in girls' ice hockey, ringette, and elite BC-permitted boys’ ice hockey.
Table 5.
Incidence rates (IRs) per 100 game-minutes and incidence rate ratios (IRRs) for total, direct (HC1), and indirect (HC2) head contacts (HCs) across adolescent ice sports. Boys’ non-bodychecking (non-BC) ice hockey served as the reference group.
| Sport | Total head contact (HC) |
Direct head contact (HC1) |
Indirect head contact (HC2) |
|||
|---|---|---|---|---|---|---|
| IR/100 game-minutes (95% CI) | IRR (95% CI) | IR/100 game-minutes (95% CI) | IRR (95% CI) | IR/100 game-minutes (95% CI) | IRR (95% CI) | |
|
Boys' ice hockey (Non elite non-BC) |
9.40 (7.25–12.19) | (Reference) | 8.63 (6.49–11.49) | (Reference) | 0.77 | (Reference) |
|
Girls' ice hockey (Elite non-BC) |
25.92 (22.05–30.48) | 2.76 (2.05–3.71)∗ | 18.04 (15.11–21.54) | 2.09 (1.51–2.90)∗ | 7.88 (6.05–10.27) | 10.24 (4.37–24.00)∗ |
|
Ringette (Elite non-BC) |
38.18 (32.91–44.30) | 4.06 (3.02–5.46)∗ | 27.44 (23.44–32.13) | 3.18 (2.30–4.39)∗ | 10.74 (8.91–12.96) | 13.96 (6.06–32.19)∗ |
|
Para ice hockey (Elite BC) |
13.33 (8.66–20.02) | 1.42 (0.70–2.88) | 11.94 (6.69–18.83) | 1.38 (0.67–2.86) | 1.39 (0.58–3.34) | 1.81 (0.56–5.79) |
|
Boys' ice hockey (Non elite BC) |
24.79 (20.50–29.97) | 2.64 (1.92–3.62)∗ | 24.79 (20.50–29.97) | 2.87 (2.05–4.02)∗ | - (no events observed) | - (no events observed) |
|
Boys' ice hockey (Elite BC) |
29.86 (26.93–33.10) | 3.18 (2.41–4.18)∗ | 19.91 (17.53–22.61) | 2.31 (1.69–3.14)∗ | 9.95 (8.37–11.84) | 12.94 (5.63–29.73)∗ |
Notes: ∗Indicates a statistically significant difference compared with boys' non-BC ice hockey.
3.3. Suspected injuries and concussions
Suspected injury outcomes varied by sport (Table 6). Compared with boys’ non-BC ice hockey, ringette showed significantly higher rates for total suspected injuries, as well as both concussion and non-concussion injuries. No other sports were statistically different from the reference group for all injuries or when broken down into concussion and non-concussion injuries.
Table 6.
Incidence rates (IRs) per 100 game-minutes and incidence rate ratios (IRRs) for total suspected injuries, concussion injuries, and non-concussion injuries across adolescent ice sports. Boys’ non-bodychecking (non-BC) ice hockey served as the reference group.
| Sport | Total injuries |
Non-concussion injuries |
Concussion injuries |
|||
|---|---|---|---|---|---|---|
| IR/100 game-minutes (95% CI) | IRR (95% CI) | IR/100 game-minutes (95% CI) | IRR (95% CI) | IR/100 game-minutes (95% CI) | IRR (95% CI) | |
|
Boys' ice hockey (Non elite non-BC) |
0.60 (0.28–1.28) | (Reference) | 0.26 (0.09–0.76) | (Reference) | 0.34 (0.14–0.86) | (Reference) |
|
Girls' ice hockey (Elite non-BC) |
1.24 (0.65–2.39) | 2.08 (0.79–5.47) | 0.62 (0.24–1.62) | 2.43 (0.60–9.81) | 0.62 (0.24–1.61) | 1.82 (0.51–6.49) |
|
Ringette (Elite non-BC) |
3.07 (2.15–4.38) | 5.13 (2.24–11.74)∗ | 1.60 (0.93–2.73) | 6.22 (1.89–20.52)∗ | 1.47 (0.90–2.41) | 4.31 (1.54–12.05)∗ |
|
Para ice hockey (Elite BC) |
0.56 (0.15–2.05) | 0.93 (0.22–3.97) | 0.28 (0.04–1.97) | 1.08 (0.13–9.30) | 0.28 (0.04–1.97) | 0.81 (0.10–6.46) |
|
Boys' ice hockey (Non elite BC) |
1.11 (0.65–1.91) | 1.86 (0.74–4.66) | 0.68 (0.34–1.36) | 2.67 (0.75–9.43) | 0.43 (0.19–0.95) | 1.25 (0.38–4.16) |
|
Boys' ice hockey (Elite BC) |
1.37 (0.92–2.04) | 2.29 (0.98–5.34) | 0.79 (0.46–1.35) | 3.08 (0.93–10.15) | 0.58 (0.32–1.06) | 1.69 (0.57–5.01) |
Notes: ∗Indicates a statistically significant difference compared with boys' non-BC ice hockey.
3.4. Penalty enforcement
Across all sports and despite illegality, direct head contacts (HC1) were rarely penalized, with enforcement ranging from 0% to 20% (Table 7). The highest proportion of illegal HC1s penalized were observed in boys' ice hockey, with a lower proportion in girls’ ice hockey and ringette, and no penalization of illegal HC1s observed in para ice hockey.
Table 7.
Number and proportion of illegal direct head contacts (HC1) penalized across adolescent ice sports.
| Sport | Direct head contacts, n | Direct head contacts penalized, n | Penalized, % | 95% CI |
|---|---|---|---|---|
| Boys' ice hockey (non elite non-BC) | 101 | 20 | 20 | 13 to 29 |
| Girls' ice hockey (elite non-BC) | 87 | 5 | 6 | 2 to 13 |
| Ringette (elite non-BC) | 447 | 31 | 7 | 5 to 10 |
| Para ice hockey (elite BC) | 43 | 0 | 0 | 0 to 8 |
| Boys' ice hockey (non elite BC) | 290 | 32 | 11 | 8 to 15 |
| Boys' ice hockey (elite BC) | 378 | 60 | 16 | 12 to 20 |
Note: BC = bodychecking; CI = confidence interval.
4. Discussion
This study provides the first direct comparison of BC, HC, and suspected injury rates across adolescent boys' and girls' ice hockey, para ice hockey, and ringette using standardized video-analysis methods. In ringette, girls' ice hockey, and some boys' ice hockey leagues, bodychecking is prohibited by sport rules, meaning intentional high-intensity trunk contact should be penalized rather than treated as permitted gameplay. Rates of BC and HC differed across sport cohorts. Ringette and girls' ice hockey demonstrated higher BC and HC rates than boys’ non-BC ice hockey, despite BC being prohibited in these sports, and ringette demonstrated the highest suspected injury and concussion rates. These findings suggest discrepancies between written sport policies and on-ice behaviours and highlight opportunities to strengthen enforcement, education, and sport-specific prevention strategies in adolescent ice sports.
4.1. Bodychecking and head contacts
The significantly higher BC and HC rates observed in ringette and girls' ice hockey suggest that rule infractions are occurring frequently without corresponding officiating response. The higher BC and HC rates observed in girls' ice hockey compared with boys’ non-BC ice hockey may reflect several interacting contextual factors, including differences in contact experience, instruction in anticipating or absorbing contact, motor skills, officiating expectations, and broader sport culture. These explanations remain speculative, as these factors were not measured directly in this study, but they may be particularly relevant in non-BC settings, where athletes may still experience high-intensity contact but may receive less contact-specific training than athletes in BC-permitted leagues. This is consistent with earlier single-sport video-analysis studies showing that a substantial proportion of BCs and HCs occur unpenalized in female adolescent leagues [[9], [10], [11], [12], [13], [14]]. These findings reinforce the need for standardized officiating education emphasizing the identification and penalization of illegal contact across all levels of play. Although officiating education and safety initiatives exist within Canadian ice sports, consistency and uptake vary by organization and level of play [15]. The absence of penalization for illegal direct HCs in para ice hockey is of particular concern and suggests that officiating enforcement may be even less consistent within this population.
4.2. Suspected injuries and concussions
Ringette demonstrated both high rates of bodychecking and the highest suspected injury and concussion rates, aligning with previous research [[12], [13], [14]]. This pattern, together with previous youth ice hockey evidence linking bodychecking policy and physical contact to injury risk, supports continued attention to illegal high-intensity contact as a potential prevention target. Possible explanations include sex-based differences in neck strength [22], neuromuscular control [23], and hormonal factors [24], alongside contextual elements such as rule differences, faster game transitions, and less protective equipment [3,4]. Given the high rates of prohibited bodychecking in non-bodychecking sport cohorts and the low penalization of direct head contacts across ice sports, the first intervention to explore should be stronger implementation of existing contact-related rules. This could include education and structural support for officials, such as preseason video-based calibration, clearer rule-interpretation guidance, and feedback processes to support consistent identification and penalization of illegal contact [15]. Aligned education for coaches, players, and parents may also be needed to reinforce that penalty enforcement is an injury prevention strategy rather than a disruption to game flow. Other complementary prevention approaches may include contact-specific skill training to help athletes anticipate, avoid, and safely respond to contact; neuromuscular training warm-ups to address modifiable movement and strength-related injury risk factors; and equipment evaluation to determine whether protective equipment influences contact behaviour or injury risk [25]. However, these strategies require sport-specific evaluation before conclusions can be drawn about their effectiveness in reducing suspected injuries or concussions in these cohorts.
These findings align with recent consensus work emphasizing that injury prevention strategies developed in boys' and men's sport should not be assumed to translate directly to female/woman/girl athletes or para-athletes without considering biological, biomechanical, equipment, policy, and social-context differences [[25], [26], [27]]. In the present study, differences in bodychecking, head contact, suspected injury, and suspected concussion rates across sport cohorts support the need for prevention strategies that are tailored to the rules, contact context, and participants in each sport.
Evidence from other youth team sports supports the importance of contact mechanism (observable characteristics of the contact event, including body region contacted, whether the head was contacted by another player or the playing environment, contact intensity, and whether the event was penalized), rather than overall contact frequency alone, in shaping concussion risk [28]. Rugby video-analysis research demonstrates that concussion risk is concentrated within contact characteristics, including direct head involvement, higher tackle height, and high-speed or forceful player interactions [28]. The legality of contact depends on the sport, league, body region contacted, contact type, and game context. Therefore, the prevention issue is not simply the presence of contact, but whether contacts that are prohibited or high-risk under existing rules are consistently identified and penalized. This is consistent with the present findings, where player-to-head contacts occurred across sport cohorts but were infrequently penalized.
4.3. Penalty enforcement
Across the included ice sports, a maximum of 20% of HC1s results in a penalty call, revealing a substantial gap between policy intent and on-ice practice. However, low penalization should be interpreted considering the realities of officiating in real time. Unlike video analysts, referees must make rapid decision during dynamic play, often without a clear view of every player and without the ability to pause, rewind, or review the event from multiple angles. These perceptual and time constraints occur alongside social pressures from players, coaches, and parents, which may further influence consistency in identifying and penalizing illegal contacts [15]. Together, these demands may contribute to under-calling even when officials understand the rules, suggesting that improved enforcement likely requires structural support in addition to education.
Embedding this support within sport organizations, through pre-season education and integration into coaching and officiating certification, could foster safer playing environments and normalize consistent enforcement of BC and HC policies. Complementary structural strategies may also be needed, such as reducing barriers to implementation, providing officials with more support or resources, or adjusting officiating structures to lessen the physical and perceptual load placed on individual referees. These broader changes acknowledge that consistent rule enforcement depends not only on individual capability, but also on opportunity and motivation shaped by the wider sport environment [29].
5. Limitations
There are several limitations to consider in this cross-sport video-analysis study, reflecting inherent challenges of video-based injury surveillance. First, although standardized coding definitions and training were used, video quality and camera positioning varied across games and seasons. Limited visibility of off-puck/ring or off-camera events may have led to an underestimation of contacts and suspected injuries. As well, identification of suspected injuries and concussions is based on observable signs rather than medical confirmation. This may underestimate true injury and concussion incidence, particularly for events with delayed symptom onset or limited visible signs. However, because these video-based limitations were likely present across all included ice sports, these limitations are expected to have affected overall event counts rather than explaining the observed between-sport differences. Second, exposure duration differed by sport (e.g., 40-min ringette vs 60-min ice hockey games), but rates were normalized per 100 game-minutes to minimize this bias. Third, the para ice hockey data were derived from a single tournament with fewer games. This may result in less precise estimates and limiting generalizability to broader para ice hockey settings. Fourth, although footage spanned multiple seasons, sensitivity analyses excluding the earliest cohort showed no meaningful impact on outcomes. However, residual temporal differences may remain. Finally, differences in competitive level (elite vs non-elite), age group, and participant characteristics across cohorts may have influenced gameplay intensity and contact patterns. These differences reflect the natural structure of adolescent sport participation in Canada, and the divisions analyzed represented the most comparable competitive levels across the included ice sports, but should be considered when interpreting cross-sport comparisons [3,5,30].
6. Perspective
This study provides novel cross-sport video-analysis evidence highlighting discrepancies between injury prevention policy and on-ice practice across adolescent ice sports. The presence of BC and HC in sports prohibiting these actions underscores the need for enhanced enforcement, education, and culture change around contact behaviour. Referees, coaches, players, and parents collectively influence game norms and can either reinforce or hinder rule compliance. These findings extend previous single-sport analyses and complement recent discussions positioning referees as critical facilitators of injury prevention policy implementation. Future work should evaluate interventions targeting officiating consistency and interest holder education to strengthen policy adherence and reduce injury and concussion risk in adolescent team ice sports.
7. Conclusion
This multiple ice sport video-analysis study highlights that despite prohibiting BC, adolescent ringette and girls' ice hockey demonstrated high rates of BCs compared to boys’ ice hockey that also prohibits BC. Ringette showed the highest suspected injury and concussion rates, and across all sports, enforcement of illegal HCs penalties was low. Collectively, these findings emphasize the urgent need for improved rule enforcement, referee education, and the implementation of tailored prevention strategies addressing sex-, gender-, and sport-specific risks in adolescent ice sports.
Declaration of competing interest
EEH and BD have no conflicts of interest to disclose. ATK holds doctoral funding through the UCalgary Eyes High Doctoral Recruitment Scholarship, Canadian Institutes of Health Research Frederick Banting and Charles Best Doctoral Scholarship, and the Izaak Walton Killam Pre-Doctoral Award. He is an external scientific member of two Hockey Canada concussion prevention working groups (unpaid). CAE holds a Canada Research Chair (Tier 1) in Concussion and research funding from Canadian Institutes of Health Research, Canada Foundation for Innovation, IOC, World Rugby and National Football League Play Smart Play Safe Program. SWW holds research funding from World Rugby.
Acknowledgements
The Sport Injury Prevention Research Centre is one of the International Research Centres for Prevention of Injury and Protection of Athlete Health, supported by the International Olympic Committee. We acknowledge funding from Canadian Institutes of Health Research, Alberta Innovates Health Solutions, Hotchkiss Brain Institute, and Alberta Children's Hospital Foundation. C.A.E. is supported by a Canada Research Chair (Tier 1) in Concussion.
Footnotes
This article is part of a special issue entitled: Concussion prevention and surveillance published in JSAMS Plus.
References
- 1.Ringette Canada annual report 2024-2025.pdf. https://www.ringette.ca/wp-content/uploads/2025/09/Annual-Report-2024-25-FINAL-EN.pdf
- 2.Hockey Canada annual report 2023-2024. https://cdn.hockeycanada.ca/hockey-canada/Corporate/About/Downloads/2023-24-hockey-canada-annual-report-e.pdf
- 3.Official Rules and Case Book 2025-2027 Ringette Canada. https://www.ringette.ca/about-us/rule-book/
- 4.Hockey Canada playing rules 2024-2026. https://cdn.hockeycanada.ca/hockey-canada/Hockey-Programs/Officiating/Downloads/rulebook_casebook_e.pdf 167.
- 5.Para Hockey Development. https://www.hockeycanada.ca/en-ca/hockey-programs/sledge
- 6.Sport Participation among children and youth Canadian fitness and lifestyle Research Institute. https://cflri.ca/publication/sport-participation-among-children-and-youth/
- 7.2024 IIHF Annual Survey of players. vol. 3. Accessed May 26, 2026. https://blob.iihf.com/iihf-media/iihfmvc/media/2025/survey/2024_iihf_annual_sop_iihf_com.pdf.
- 8.Ringette History National ringette school. https://nationalringetteschool.com/ringette/facts
- 9.Williamson R.A., Cairo A.L., Heming E.E., Kolstad A.T., Hagel B.E., Emery C.A. Physical contact and suspected injury rates in female versus Male youth ice hockey: a video-analysis study. Clin J Sport Med. 2023;33(6):638–642. doi: 10.1097/JSM.0000000000001149. [DOI] [PubMed] [Google Scholar]
- 10.Dennett B. ME09 – moderated E-Poster Session 02 – station 3, Station 3, March 1, 2024, 12:30 – 13:30. BMJ Publishing Group Ltd and British Association of Sport and Exercise Medicine; 2024. Breaking the ice: analyzing head contacts, physical contacts, and video-suspected injury rates in community para ice hockey; p. A164.1. A164. [DOI] [Google Scholar]
- 11.Kolstad A.T., Chin M., Martinez G., Janzen L., Krolikowski M., Goulet C., et al. Evaluating the effect of Policy prohibiting body checking on physical contacts in U15 and U18 youth ice hockey leagues. Clin J Sport Med. 2022;32(6):e614–e619. doi: 10.1097/JSM.0000000000001060. [DOI] [PubMed] [Google Scholar]
- 12.Heming E.E., Kolstad A.T., West S.W., Williamson R.A., Sobry A.J., Galarneau J.M., et al. Blow the whistle: a cross-sectional video-analysis study examining bodychecking, suspected injuries and penalisation of illegal contacts in youth ringette. BMJ Open Sport Exerc Med. 2026;12(2) doi: 10.1136/bmjsem-2025-002693. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 13.Heming E.E., Sobry A.J., Cairo A.L., Williamson R.A., Kolstad A.T., West S.W., et al. Higher rates of head contacts, body checking, and suspected injuries in ringette than female ice hockey: time to ring in opportunities for prevention. Clin J Sport Med. 2023;33(2):151–156. doi: 10.1097/JSM.0000000000001089. [DOI] [PubMed] [Google Scholar]
- 14.Heming E.E., Kolstad A.T., West S.W., Williamson R.A., Sobry A.J., Cairo A.L., et al. Time to ring in the body checking, head contact, and suspected injury rates in youth ringette: a video-analysis Study in youth ringette and female ice hockey. Clin J Sport Med. 2024;35(2):184–190. doi: 10.1097/JSM.0000000000001293. [DOI] [PubMed] [Google Scholar]
- 15.West S.W., Heming E.E., Klassen C., Lewis K., Emery C.A. Whistleblower: the front line and critical facilitator for injury prevention policy? Inj Prev. 2025;31(5):349–351. doi: 10.1136/ip-2025-045744. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 16.Malenfant S., Goulet C., Nadeau L., Hamel D., Emery C.A. The incidence of behaviours associated with body checking among youth ice hockey players. J Sci Med Sport. 2012;15(5):463–467. doi: 10.1016/j.jsams.2012.03.003. [DOI] [PubMed] [Google Scholar]
- 17.Dartfish V 10.0. Dartfish Video analysis software.
- 18.Andersen T.E. Football incident analysis: a new video based method to describe injury mechanisms in professional football. Br J Sports Med. 2003;37:226–232. doi: 10.1136/bjsm.37.3.226. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 19.West S.W., Shill I.J., Sutter B., George J., Ainsworth N., Wiley J.P., et al. Caught on camera: a video assessment of suspected concussion and other injury events in women's rugby union. J Sci Med Sport. 2022;25(10):805–809. doi: 10.1016/j.jsams.2022.07.008. [DOI] [PubMed] [Google Scholar]
- 20.Davis G.A., Makdissi M., Bloomfield P., Clifton P., Echemendia R.J., Falvey É.C., et al. International consensus definitions of video signs of concussion in professional sports. Br J Sports Med. 2019;53(20):1264–1267. doi: 10.1136/bjsports-2019-100628. [DOI] [PubMed] [Google Scholar]
- 21.StataCorp Stata Statistical Software: Release. 2021;17 Published online. [Google Scholar]
- 22.Williams E.M.P., Petrie F.J., Pennington T.N., Powell D.R.L., Arora H., Mackintosh K.A., et al. Sex differences in neck strength and head impact kinematics in university rugby union players. Eur J Sport Sci. 2022;22(11):1649–1658. doi: 10.1080/17461391.2021.1973573. [DOI] [PubMed] [Google Scholar]
- 23.Landry S.C., McKean K.A., Hubley-Kozey C.L., Stanish W.D., Deluzio K.J. Gender differences exist in neuromuscular control patterns during the pre-contact and early stance phase of an unanticipated side-cut and cross-cut maneuver in 15–18 years old adolescent soccer players. J Electromyogr Kinesiol. 2009;19(5):e370–e379. doi: 10.1016/j.jelekin.2008.08.004. [DOI] [PubMed] [Google Scholar]
- 24.La Fountaine M.F., Hill-Lombardi V., Hohn A.N., Leahy C.L., Testa A.J. Preliminary evidence for a window of increased vulnerability to sustain a concussion in females: a brief report. Front Neurol. 2019;10:691. doi: 10.3389/fneur.2019.00691. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 25.Crossley K.M., Whittaker J.L., Patterson B., Shill I.J., Heming E.E., Bullock G.S., et al. Female, woman and/or girl Athlete Injury pRevention (FAIR) practical recommendations: International Olympic Committee (IOC) consensus meeting held in Lausanne, Switzerland, 2025. Br J Sports Med. 2025;59(22):1546–1559. doi: 10.1136/bjsports-2025-110889. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 26.Heming E.E., West S.W., Patterson B., Bullock G.S., McHugh T.L., Shill I.J., et al. Raising girls in sport: unique considerations for injury prevention. Br J Sports Med. 2025;59(22):1531–1533. doi: 10.1136/bjsports-2025-111034. [DOI] [PubMed] [Google Scholar]
- 27.Grimes A.C., Harrington (Quinn) N., Blauwet C., Ahmed O.H., Gavel-Pinos E.H., Mitchell K.M., et al. Towards an evidence-informed future in injury prevention: a call to action for female, women and girls in para sport. Br J Sports Med. 2025;59(22):1534–1535. doi: 10.1136/bjsports-2025-111037. [DOI] [PubMed] [Google Scholar]
- 28.Shill I.J., West S.W., Galarneau J.M., Omokuale J., Hendricks S., Pike I., et al. Tackle characteristics and suspected concussion: recommendations to improve high school girls' rugby tackle safety. BMJ Open Sport Exerc Med. 2025;11(3) doi: 10.1136/bmjsem-2025-002573. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 29.Michie S., Van Stralen M.M., West R. The behaviour change wheel: a new method for characterising and designing behaviour change interventions. Implement Sci. 2011;6(1):42. doi: 10.1186/1748-5908-6-42. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 30.Hockey Canada Age Divisions | Age range info for minor hockey. https://www.hockeycanada.ca/en-ca/hockey-programs/players/essentials/age-divisions