Did injury incidence in alpine ski racing change after equipment regulations? An evaluation based on the injury surveillance system of the Austrian Ski Federation.

OBJECTIVES: To assess the effects of alpine competition equipment regulations from 2003, 2007 and 2012 on severe injury incidence. DESIGN: Case study METHOD: Data originated from records of the injury surveillance system of the Austrian Ski Federation. Injuries from the seasons 2001-2017 were divided in four periods between the equipment regulations. For comparison of consecutive periods, risk ratios (RR = later period / preceding period) with 95% CI were calculated. Total severe injury events, events with severe knee injuries, and events with severe ACL injuries were separately investigated. RESULTS: A significant increase of total severe injury incidence was found after the equipment regulation in 2003 (RR1.52, 95% CI 1.00-2.31). None of the other comparisons revealed significance (p<0.05) or statistical trends (p<0.1). Only the minority (40%) of the RR showed a reduction in the injury incidence of the Austrian Ski Team (lowest RR 0.78). 60% of the RR increased after the regulations (highest RR 1.63). CONCLUSIONS: Even though statistical uncertainties remain, our findings allow the conclusion, that the implemented equipment regulations did not cause a noticeable reduction of injuries. The three analysed equipment regulations were not appropriate or were counteracted by other factors.

Managing head injury risks in competitive skateboarding: what do we know?

OBJECTIVES: The broad objective of this paper is to inform policy, practice and research regarding the management of head injury risks in competitive skateboarding. The main motivation for the current study was the question of mandating helmet use in competitive skateboarding. The specific aims are to present current knowledge on (A) head injury risks in skateboarding, (B) preliminary biomechanical data on falls and head injury risks in a selection of competitive skateboarding events similar to those planned for the Summer Olympics, (C) standards for skateboard-styled helmets and (D) impact performance of helmets commonly used in skateboarding. METHODS: A narrative review of the published literature on head injuries in skateboarding was conducted. Videos of skateboarding competitions from Vans Park Professional League, Street League Skateboarding and Dew Tour were reviewed to describe crashes and falls. Standards databases including the International Organization for Standardization (ISO), British Standards Institution (BSI), Snell, United States Consumer Product Safety Commission (CPSC) and American Society for Testing and Materials (ASTM) were searched for skateboarding-styled helmet standards. A sample of helmets considered suitable for skateboarding was tested in standard impact tests. RESULTS: The majority of previous literature focused on the paediatric population in a recreational setting with little data from competitive skateboarding. Head injuries comprised up to 75% of all injuries and helmet use was less than 35%. Video analysis identified high rates of falls and crashes during competitive skateboarding, but also a capacity for the athletes to control falls and limit head impacts. Less than 5% of competitive skateboarders wore helmets. In addition to dedicated national skateboard helmet standards, there are several national standards for skateboard-styled helmets. All helmets, with the exception of one uncertified helmet, had similar impact attenuation performance; that is, at 0.8 m drop height, 114-148 g; at 1.5 m, 173-220 g; and at 2.0 m, 219-259 g. Impact performance in the second impact was degraded in all helmets tested. CONCLUSION: Helmets styled for skateboarding are available 'off the shelf' that will offer protection to the head against skull fractures and intracranial injuries in competitive skateboarding. There is an urgent need to commence a programme of research and development to understanding and control head injury risks.

The relationship between trunk rotation and shot speed when performing ice hockey wrist shots.

There has been minimal work examining kinematics of ice hockey wrist shots. The objective was to determine if puck and blade speed were related to trunk rotation during wrist shots in elite and recreational players. Elite (n = 10) and recreational (n = 10) ice hockey players completed wrist shots while skating and from a stationary position on real ice. A 14 camera motion capture system collected kinematic data for the trunk, pelvis, stick, and puck. Dependent variables included peak puck and blade speeds. Independent variables included peak trunk rotation angles, trunk rotation range of motion (ROM), and group (elite vs. recreational). Hierarchical linear models compared relationships between dependent and independent variables for both skating and stationary wrist shots. Greater peak trunk rotation away from the net was related (p < 0.05) to faster puck and blade speeds for skating and stationary wrist shots. This relationship was stronger in the recreational group for skating wrist shots (p < 0.01). Greater trunk rotation ROM was related (p = 0.01) to faster puck and blade speeds for the skating wrist shots only. Coaches should encourage players to increase trunk rotation away from the net during wrist shots, especially in recreational players.

Children's coordination of the "sweet spot" when striking a forehand is shaped by the equipment used.

Children's movement coordination is significantly influenced by the equipment used when performing multi-articular actions. Previously we reported that scaled equipment (smaller racket and a softer ball), but not full-sized equipment, promoted a functional coupling between upper arm and forearm angles in children performing a forehand. However, it remains unclear whether the shoulder-racket distance-which is controlled by this coupling-is a performance variable. This study therefore advanced previous research by examining whether the shoulder-racket distance is associated with performance. We also improved our understanding of how the shoulder-racket distance is controlled by including the hand-racket segment in our biomechanical model. Twenty-one children performed 40 forehands in a hitting for accuracy task. Participants were randomly divided into two groups-a scaled equipment group and a full-sized equipment group. Results revealed that the shoulder-racket distance was a performance variable, as evidenced by: (a) its variance reduced closer to ball impact, (b) its distance at ball impact, but not at the start of the forward swing, differentiated good from poor performance, and (c) its distance was similar for both groups, implying that there was a "sweet spot" for striking a ball, regardless of racket size. We also showed that it is the shoulder-racket vector in state-space (i.e., distance and angle) that differentiates good from poor performance. Finally, the manner in which the shoulder-racket distance was controlled differed between the groups, with scaled equipment promoting a more distal control than full-sized equipment. Implications for skill acquisition are discussed.

La observación en contexto de los niveles de acción en balonmano / The Observation in Context of Level Actions in Team Handball

Esta investigación plantea como objetivo principal diseñar un instrumento de registro que permita describir y relacionar tres niveles de acción del balonmano (juego de equipo, juego grupal y juego individual), vinculándolos al contexto de competición y atendiendo a su eficacia. Siguiendo las directrices de la metodología observacional se opta por un sistema combinado de formatos de campo y sistema de categorías, utilizando un diseño de investigación de carácter ideográfico, puntual y multidimensional. Se utiliza como instrumento de registro el software Dartfish TeamPro V.4.5 para analizar siete partidos de categoría absoluta, y siete partidos de categoría infantil, generándose datos de tipo concurrente y de evento. Se aplican técnicas estadísticas descriptivas e inferenciales bivariadas para el análisis relacional de los datos. Destacamos los resultados que constatan la asociación entre sistemas de juego y procedimientos colectivos tanto ofensivos como defensivos, y la dificultad en establecer relaciones significativas entre el ataque y la defensa

The main aim of this research was to design a recording tool that allows describing and relating three levels of action in team handball (team play, group play and individual play), linking them to the competition context and taking their effectiveness into account. Following the guidelines of observational methodology, we selected a combined system of field formats and system of categories, using an ideographic, specific and multidimensional research design. Dartfish TeamPro V.4.5 software, was used as a recording instrument to analyse seven matches in the top category, and seven matches in the children's category, generating concurrent and event data. Bivariate descriptive and inferential statistical techniques were used for the relational analysis of the data. The results confirmed the association between game systems and collective procedures, both offensive and defensive, as well as the difficulty to establish significant relationships between attack and defense

Proposed injury thresholds for concussion in equestrian sports.

OBJECTIVES: Equestrian helmets are designed to pass certification standards based on linear drop tests onto rigid steel surfaces. However, concussions in equestrian sports occur most commonly when a rider is thrown off a horse and obliquely impacts a compliant surface such as turf or sand. This paper seeks to elucidate the mechanics of such impacts and thereby propose corresponding thresholds for the occurrence of concussion that can improve equestrian helmet standards and designs. DESIGN: The present study examined the biomechanics of real-world equestrian accidents and developed thresholds for the occurrence of concussive injury. METHODS: Twenty-five concussive and 25 non-concussive falls in equestrian sports were reconstructed using a combination of video analysis, computational and physical reconstruction methods. These represented male and female accidents from horse racing and the cross-country phase of eventing. RESULTS: The resulting thresholds for concussion [59g, 2700rad/s2, 28rad/s, 0.24 (MPS), 6.6kPa and 0.27 (CSMD10) for 50% risk] were consistent with those reported in the literature and represent a unique combination of head kinematic thresholds compared to other sports. Current equestrian helmet standards commonly use a threshold of 250g and a linear drop to a steel anvil resulting in less than 15ms impacts. This investigation found that concussive equestrian accidents occurred from oblique impacts to turf or sand with lower magnitude and longer duration impacts (<130g and >20ms). This suggests that current equestrian helmet standards may not adequately represent real-world concussive impact conditions and, consequently, there is an urgent need to assess the protective capacity of equestrian helmets under real-world conditions.

Event-specific impact test protocol for ice hockey goaltender masks.

Goaltenders in the sport of ice hockey are at high risk for concussions from falls to the ice, player collisions and puck impacts. However, current methods used to certify helmets only consider head accelerations for drop tests which may not describe all common injury mechanisms relating to concussion. The purpose of this study was to describe the characteristics of 3 events associated with concussions for ice hockey goaltenders. A helmeted medium National Operating Committee on Standards for Athletic Equipment (NOCSAE) headform was impacted under conditions representing 3 injury events. Three impact locations' velocities were selected for each event based on video analysis of real-world concussive events. Peak resultant linear acceleration, rotational acceleration and rotational velocity of the headform were measured. The University College Dublin Brain Trauma Model (UCDBTM) was used to calculate maximum principal strain (MPS) and von Mises stress in the cerebrum. Each impact event produced a unique dynamic response and brain stress and strain values. This demonstrates that a single impact event (i.e. falls) cannot adequately describe all impact events. As a result, impact protocols which assess multiple impact events such as the protocol described in this study should be used to evaluate ice hockey goaltender masks.

Portero-jugador en situaciones de inferioridad numérica ofensiva en balonmano: ¿penalización o ventaja? / Goalkeeper-field player in situations of offensive numerical inferiority in handball: penalty or advantage?

El objetivo principal fue analizar el resultado final de la acción ofensiva entre los equipos que utilizan, o no, el portero-jugador en situaciones de inferioridad numérica ofensiva en balonmano. Los objetivos secundarios se centran en analizar cómo es la utilización y el comportamiento del portero-jugador y su relación con el resultado final ofensivo y la posterior acción con respecto al contraataque del equipo contrario. Se analizaron las actas oficiales de 86 partidos del 22º Campeonato del Mundo de Balonmano Femenino (Dinamarca 2015) y se realizó el visionado, análisis y registro de las 927 situaciones de inferioridad numérica ofensiva, así como el estudio estadístico pertinente con SPSS v.24. Los resultados demuestran que el uso del recurso táctico o estratégico del portero-jugador favorece la obtención de gol en situaciones de inferioridad numérica ofensiva y no penaliza al equipo que lo utiliza, al no existir diferencia significativa en la probabilidad de recibir gol en contraataque

The main goal was to analyze the end results in offensive actions between teams that do or do not employ the goalkeeper-field player in situations of offensive numerical inferiority in handball. The secondary objectives focus on analyzing the use and behavior of the goalkeeper-field player, as well as its role in the final offensive result and following actions in terms of the opposing team's counterattack. 86 official match reports from the 22nd Women's Handball World Championship (Denmark 2015) were analyzed, and the viewing, analysis and registration of the 927 situations of offensive numerical inferiority were carried out, as well as the pertinent statistical study with SPSS v.24. The results show that the tactical or strategic use of the goalkeeper-field player favors goal scoring in situations of offensive numerical inferiority and does not punish the team which employs it, since there's no significant difference in the probability of conceding a goal in counterattack

Repeated Impacts Diminish the Impact Performance of Equestrian Helmets.

Context: During thoroughbred races, jockeys are placed in potentially injurious situations, often with inadequate safety equipment. Jockeys frequently sustain head injuries; therefore, it is important that they wear appropriately certified helmets. Objective: The goals of this study are (1) to perform impact attenuation testing according to ASTM F1163-15 on a sample of equestrian helmets commonly used by jockeys in the United States and (2) to quantify headform acceleration and residual crush after repeat impacts at the same location. Participants and Design: Seven helmet models underwent impact attenuation testing according to ASTM F1163-15. A second sample of each helmet model underwent repeat impacts at the crown location for a total of 4 impacts. Setting: Laboratory. Intervention: Each helmet was impacted against a flat and equestrian hazard anvil. Main Outcome Measures: Headform acceleration was recorded during all impact and computed tomography scans were performed preimpact and after impacts 1 and 4 on the crown to quantify liner thickness. Results: Four helmets had 1 impact that exceeded the limit of 300g. During the repeated crown impacts, acceleration remained below 300g for the first and second impacts for all helmets, while only one helmet remained below 300g for all impacts. Foam liner thickness was reduced between 5% and 39% after the first crown impact and between 33% and 70% after the fourth crown impact. Conclusions: All riders should wear a certified helmet and replace it after sustaining a head impact. Following an impact, expanded polystyrene liners compress, and their ability to attenuate head acceleration during subsequent impacts to the same location is reduced. Replacing an impacted helmet may reduce a rider's head injury risk.

The association of bike fitting with injury, comfort, and pain during cycling: An international retrospective survey.

Although bike fitting is recommended to help reduce injury risk, little empirical evidence exists to indicate an association between bike fitting and injury incidence. The aim of the study was to determine the effect of bike fitting on self-reported injury, comfort, and pain while cycling from a worldwide survey of cyclists. A total of 849 cyclists completed an online questionnaire between February and October 2016. Questionnaire collected data on respondent demographics, cycling profile, bike fitting, comfort and pain while cycling, and injury history. The main predictor variable was bike fitting (yes, by the respondent, i.e. user bike fitting; yes, by a professional service; or no). Covariates included demographic and cycling profile characteristics. Logistic regression models estimated the odds of injury within the last 12 months, reporting a comfortable body posture while cycling, and not reporting pain while cycling. Odds ratios (OR) with 95% confidence intervals (CI) were reported. User bike fitting was associated with increased odds of reporting a comfortable posture (OR = 2.28, 95%CI: 1.06, 4.68). User (OR = 2.35; 95%CI: 1.48, 3.84) and professional bike fitting (OR = 2.35; 95%CI: 1.42, 3.98) were both associated with increased odds of not reporting pain while cycling. No associations were found between bike fitting and injury within the last 12 months. In conclusion, we found an association between bike fitting and reported comfort and pain while cycling. We recommend integrating bike fitting into cycling maintenance. However, further studies with longer follow-up are necessary to determine the presence of an association between bike fitting and injury.

The Effects of Various Weighted Implements on Baseball Swing Kinematics in Collegiate Baseball Players.

Williams, CC, Gdovin, JR, Wilson, SJ, Cazas-Moreno, VL, Eason, JD, Hoke, EL, Allen, CR, Wade, C, and Garner, JC. The effects of various weighted implements on baseball swing kinematics in collegiate baseball players. J Strength Cond Res 33(5): 1347-1353, 2019-The purpose of this study was to investigate the effects of different warm-up (WU) devices on bat swing parameters including maximal resultant velocity (MRV), resultant velocity at ball contact (RVBC), time difference between MRV and RVBC, bat angle at MRV, bat angle at RVBC, and perceptual differences of each WU implement used by National Collegiate Athletic Association Division-I baseball players. Fifteen varsity baseball players completed 1 experimental session during fall training. Retroreflective markers were placed on the bat and tee to measure basic bat kinematics during the swing. Participants completed a general calisthenics WU before being counter-balanced into 1 of 4 WU conditions: standard bat (SB) (33 in/30 oz), fungo (10.6 oz), weighted gloves with SB (weighted gloves) (55.6 oz) and donut with SB (donut) (55.6 oz). Each participant was asked to perform their normal on-deck routine over a 2-minute period, finishing with 5 practice swings with the designated condition. After completion of the WU, a 1-minute rest period (simulating normal game conditions) was given to allow each participant to get set to perform 5 maximal swings with a SB. Five, 1 × 4 (group × condition) repeated measures analysis of variance examined the aforementioned variables. There were no significant differences in MRV, RVBC, time difference between MRV and RVBC, and bat angle at MRV and RVBC between all WU conditions. If presented with the current options, athletes should choose the WU implement with which they are most comfortable using before an at-bat situation.

Formación de codificadores y fiabilidad de los registros. Una aplicación al goalball / Training of coders and reliability. An application to the goalball

El propósito de este artículo es describir el proceso de formación y evaluación de la fiabilidad inter-observador de los cinco codificadores participantes en un estudio sobre el análisis del rendimiento competitivo en goalball de alta competición. Los codificadores participaron en un proceso de formación consistente en seis sesiones presenciales en grupo y cuatro ejercicios prácticos individuales y no presenciales, distribuidos en tres fases; Teórica, Práctica y de Entrenamiento. Tras las dos primeras se procedió al cálculo de la fiabilidad durante el desarrollo de la fase de entrenamiento a través de la prueba Multirather Kappa Free, obteniendo finalmente un nivel de fiabilidad inter-observador casi perfecto (>0,86) en todas las variables definidas para el estudio, lo que permitió la codificación de las acciones de los partidos registrados de Goalball que conformaron la muestra del mismo

The purpose of this paper is to describe the training process and inter-rather reliability evaluation of five coders involved in a research about performance analysis of sport in goalball. The coders participated in a training process, consisted of six face-to-face sessions and four individual exercises, distributed in three phases; Theoretical, Practical and training. After the first two phases, reliability was measured during the development of training period using Multirather Kappa Free. Finally, an almost perfect level of inter-rather reliability (>.86) was obtaining in all variables defined for the research, allowing codificate all goalball match actions that formed the sample

Is Helmet and Faceguard Modification Common in Hurling and Camogie and Why Is It Done?

Aims Despite no previous research, it is anecdotally reported that hurling and camogie players modify their helmet and faceguard, which is against GAA regulations and can potentially increase injury risk. This study aimed to establish the prevalence and rationale behind modifications in hurling and camogie. Methods An online questionnaire was completed by 304 players aged over 18 (62% hurlers, 38% camogie players) which consisted of 27 questions. Results Appearance (43%) was the primary reasons for helmet brand choice, with just 1.6% citing safety as a main reason for choice. Surprisingly, 8% of helmets were already modified when purchased and 31% of participants made further modifications, primarily switching faceguards and removal of bars. Restricted vision, comfort and perceived poor quality of the helmet/faceguard were the most common reasons for modification. Players predominantly (75.8%) agreed that further education on modifications is required. Conclusion Future research on the relationship between helmet/faceguard modification and injury risk is required.

Foul tip impact attenuation of baseball catcher masks using head impact metrics.

Currently, no scientific consensus exists on the relative safety of catcher mask styles and materials. Due to differences in mass and material properties, the style and material of a catcher mask influences the impact metrics observed during simulated foul ball impacts. The catcher surrogate was a Hybrid III head and neck equipped with a six degree of freedom sensor package to obtain linear accelerations and angular rates. Four mask styles were impacted using an air cannon for six 30 m/s and six 35 m/s impacts to the nasion. To quantify impact severity, the metrics peak linear acceleration, peak angular acceleration, Head Injury Criterion, Head Impact Power, and Gadd Severity Index were used. An Analysis of Covariance and a Tukey's HSD Test were conducted to compare the least squares mean between masks for each head injury metric. For each injury metric a P-Value less than 0.05 was found indicating a significant difference in mask performance. Tukey's HSD test found for each metric, the traditional style titanium mask fell in the lowest performance category while the hockey style mask was in the highest performance category. Limitations of this study prevented a direct correlation from mask testing performance to mild traumatic brain injury.

Tiros libres indirectos en fútbol de alto nivel. Identificación de variables explicativas / Indirect free kicks in football high performance. Identification of explanatory variables

Los tiros libres indirectos son situaciones que se producen durante los partidos de fútbol, siendo acciones potencialmente trascendentales en el resultado final. Los objetivos fueron determinar la efectividad de estas acciones, identificar las variables asociadas con el éxito, y proponer un modelo de tiro libre indirecto exitoso. Tras registrar 447 tiros libres indirectos durante los 64 partidos del Mundial de Sudáfrica 2010, y de realizar análisis estadístico, los resultados indican una baja eficacia en el remate, remate entre los tres palos y el gol. El 64,3% de los goles con procedencia en un tiro libre indirectos han contribuido a sumar puntos en el resultado final. El modo de envío, número de atacantes que intervienen y la organización ofensiva son variables que se han revelado como moduladoras de la eficacia. Estos enunciados podrían suponer un punto de partida para dotar a entrenadores de nuevas herramientas tácticas

Indirect free kicks are situations that occur during football matches, with potentially transcendental actions in the final result. The objectives were to determine the effectiveness of these actions, identify variables associated with success, and propose a successful indirect free kick model. After registering 447 indirect free kicks during the 64 games of the World Cup in South Africa 2010, and performing statistical analysis, results indicate a low efficiency in the shot, shot between the three posts and goal. 64.3 % of goals that came from indirect free kick contributed to score points in the final result. The mode of sending, number of attackers involved and the offensive organization are variables that have been revealed as modulators of effectiveness. These statements could be a starting point to equip coaches with new tactical tools

Pole lengths influence O2-cost during double poling in highly trained cross-country skiers.

PURPOSE: In elite cross-country skiing, double poling is used in different terrain. This study compared O2-cost and kinematics during double poling with four different pole lengths [self-selected (SS), SS - 5 cm, SS + 5 cm, SS + 10 cm] at Low versus Moderate incline. METHODS: Thirteen highly trained male cross-country skiers (mean ± SD 23 ± 3 years; 182 ± 4 cm; 77 ± 6 kg) completed eight submaximal trials with roller skis on a treadmill at two conditions: "Low incline" (1.7°; 4.5 m s-1) and "Moderate incline" (4.5°; 2.5 m s-1) with each of the four pole lengths. O2-cost and 3D body kinematics were assessed in each trial. RESULTS: In Low incline, SS + 10 cm induced a lower O2-cost than all the other pole lengths [P < 0.05; effect size (ES) 0.5-0.8], whereas no differences were found between the remaining pole lengths (P > 0.05; ES 0.2-0.4). In Moderate incline, significant differences between all pole lengths were found for O2-cost, with SS - 5 cm > SS > SS + 5 cm > SS + 10 cm (P < 0.05; ES 0.6-1.8). The relative differences in O2-cost between SS and the other pole lengths were greater in Moderate incline than Low incline (SS - 5 cm; 1.5%, ES 0.8, SS + 5 cm; 1.3%, ES 1.0, and SS + 10 cm; 1.9%, ES 1.0, all P < 0.05). No difference was found in cycle, poling or reposition times between pole lengths. However, at both conditions a smaller total vertical displacement of center of mass was observed with SS + 10 cm compared to the other pole lengths. CONCLUSION: Increasing pole length from SS - 5 cm to SS + 10 cm during double poling induced lower O2-cost and this advantage was greater in Moderate compared to Low incline.

The Ability of an Aftermarket Helmet Add-On Device to Reduce Impact-Force Accelerations During Drop Tests.

CONTEXT: The Guardian Cap provides a soft covering intended to mitigate energy transfer to the head during football contact. Yet how well it attenuates impacts remains unknown. OBJECTIVE: To evaluate the changes in the Gadd Severity Index (GSI) and linear acceleration during drop tests on helmeted headforms with or without Guardian Caps. DESIGN: Crossover study. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: Nine new football helmets sent directly from the manufacturer. INTERVENTION(S): We dropped the helmets at 3 velocities on 6 helmet locations (front, side, right front boss, top, rear right boss, and rear) as prescribed by the National Operating Committee on Standards for Athletic Equipment. Helmets were tested with facemasks in place but no Guardian Cap and then retested with the facemasks in place and the Guardian Cap affixed. MAIN OUTCOME MEASURE(S): The GSI scores and linear accelerations measured in g forces. RESULTS: For the GSI, we found a significant interaction among drop location, Guardian Cap presence, and helmet brand at the high velocity (F10,50 = 3.01, P = .005) but not at the low (F3.23,16.15 = 0.84, P = .50) or medium (F10,50 = 1.29, P = .26) velocities. Similarly for linear accelerations, we found a significant interaction among drop location, Guardian Cap presence, and helmet brand at the high velocity (F10,50 = 3.01, P = .002, ω2 = 0.05) but not at the low (F10,50 = 0.49, P = .89, ω2 < 0.01, 1-ß = 0.16) or medium (F5.20,26.01 = 2.43, P = .06, ω2 < 0.01, 1-ß = 0.68) velocities. CONCLUSIONS: The Guardian Cap failed to significantly improve the helmets' ability to mitigate impact forces at most locations. Limited evidence indicates how a reduction in GSI would provide clinically relevant benefits beyond reducing the risk of skull fracture or a similar catastrophic event.

Temperate-Water Immersion as a Treatment for Hyperthermic Humans Wearing American Football Uniforms.

CONTEXT: Cold-water immersion (CWI; 10°C) can effectively reduce body core temperature even if a hyperthermic human is wearing a full American football uniform (PADS) during treatment. Temperate-water immersion (TWI; 21°C) may be an effective alternative to CWI if resources for the latter (eg, ice) are unavailable. OBJECTIVE: To measure rectal temperature (Trec) cooling rates, thermal sensation, and Environmental Symptoms Questionnaire (ESQ) scores of participants wearing PADS or shorts, undergarments, and socks (NOpads) before, during, and after TWI. DESIGN: Crossover study. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: Thirteen physically active, unacclimatized men (age = 22 ± 2 years, height = 182.3 ± 5.2 cm, mass = 82.5 ± 13.4 kg, body fat = 10% ± 4%, body surface area = 2.04 ± 0.16 m2). INTERVENTION(S): Participants exercised in the heat (40°C, 50% relative humidity) on 2 days while wearing PADS until Trec reached 39.5°C. Participants then underwent TWI while wearing either NOpads or PADS until Trec reached 38°C. Thermal sensation and ESQ responses were collected at various times before and after exercise. MAIN OUTCOME MEASURE(S): Temperate-water immersion duration (minutes), Trec cooling rates (°C/min), thermal sensation, and ESQ scores. RESULTS: Participants had similar exercise times (NOpads = 38.1 ± 8.1 minutes, PADS = 38.1 ± 8.5 minutes), hypohydration levels (NOpads = 1.1% ± 0.2%, PADS = 1.2% ± 0.2%), and thermal sensation ratings (NOpads = 7.1 ± 0.4, PADS = 7.3 ± 0.4) before TWI. Rectal temperature cooling rates were similar between conditions (NOpads = 0.12°C/min ± 0.05°C/min, PADS = 0.13°C/min ± 0.05°C/min; t12 = 0.82, P = .79). Thermal sensation and ESQ scores were unremarkable between conditions over time. CONCLUSIONS: Temperate-water immersion produced acceptable (ie, >0.08°C/min), though not ideal, cooling rates regardless of whether PADS or NOpads were worn. If a football uniform is difficult to remove or the patient is noncompliant, clinicians should begin water-immersion treatment with the athlete fully equipped. Clinicians should strive to use CWI to treat severe hyperthermia, but when CWI is not feasible, TWI should be the next treatment option because its cooling rate was higher than the rates of other common modalities (eg, ice packs, fanning).