Female Ice Hockey Players Research Articles

Mechanical determinants of forward skating sprint inferred from off- and on-ice force-velocity evaluations in elite female ice hockey players

This study aimed to investigate the correlations between players’ mechanical capacities determined during off- and on-ice tests. Whole body force-velocity relationships were assessed in elite female ice hockey players (n = 17) during jumping [squat jump (SJ)], running (5 and 30 m) and skating (5 and 40 m) sprint tasks. Mechanical capacities estimates include relative maximal theoretical force (F0rel), velocity (V0), power (Pmaxrel), slope of the linear relationship between force relative to body mass and velocity (SFVrel), maximal horizontal component of the ground reaction force to the corresponding resultant force (RFmax) and minimal rate of decrease of this ratio (DRF). On-ice mechanical capacities (F0rel, Pmaxrel, RFmax and DRF) largely-to-very largely correlated with 40-m skating split time (r ranging from 0.82 for DRF to −0.91 for Pmaxrel; p < 0.001). Performance variables (SJ height, 30-m running and 40-m forward skating split time) and Pmaxrel demonstrated the largest associations between jumping, running and skating tasks (r ranging from −0.81 for 30-m sprint running time to 0.92 for SJ height; p < 0.001). Small (V0, SFVrel, DRF and force-velocity deficit) to very large (Pmaxrel) correlations (r ranging from 0.58 to 0.72; p < 0.05) were obtained between mechanical variables inferred from off- and on-ice force-velocity tests. The capacity to generate high amounts of horizontal power and effective horizontal force during the first steps on the ice is paramount for forward skating sprint performance. Mechanical capacities determined during forward skating sprint could be considered in ice hockey testing to identify fitness and/or technical/training requirements.

Youth Female Ice Hockey Players’ Enjoyment and Commitment to Sport

The purpose of this study was to identify sport-specific predictors of youth female athletes’ sport commitment and sport enjoyment. Based on the expectancy-value model, athletic identity and gender stereotypes were hypothesized to predict sport commitment and sport enjoyment in ice hockey, which has a masculine gender association. Participants consisted of 130 (89.2% Caucasian) youth female ice hockey players (Mage = 11.7, SD = 2.6). They completed measures of athletic identity; personal gender beliefs; perceived gender beliefs of parents, teammates, siblings, and the general population; and two outcome measures: sport commitment and sport enjoyment. The prediction model for sport commitment was significant, F(7, 122) = 9.56, p &lt; .001, and accounted for 35.4% of the variance. The prediction model for sport enjoyment was also significant, F(7, 122) = 2.25, p &lt; .01, and accounted for 11.5% of the variance. Overall, youth female ice hockey players held pro-feminine beliefs about competence and values of girls in hockey. Participants’ personal gender beliefs correlated moderately with perceived gender beliefs of their (socializers) parents, teammates, and the general population (r = .54–.56), suggesting youth female ice hockey players’ pro-feminine beliefs might be informed by these social influences. However, two multiple mediation analyses found no support for the hypotheses that personally held stereotypes mediated the link between all four socially based gender stereotypes and enjoyment and commitment.

Characterizing the Prevalence of Cam-Type Hip Impingement in Professional Women’s Ice Hockey Players

BackgroundRecent studies have demonstrated a high prevalence of femoroacetabular impingement (FAI) in elite men’s ice hockey players, yet little is known about the hips of elite women’s ice hockey players.PurposeThe primary purpose of this study was to determine the prevalence of radiographic cam-type FAI in professional women’s ice hockey players in the National Women’s Hockey League (NWHL). The secondary purpose was to analyze the relationship between the presence of cam deformity and both hip range-of-motion (ROM) and age of menarche.MethodsClinical, radiographic and demographic data were collected during player pre-participation physicals. ROM measurements were performed with a goniometer. Alpha angles were measured on 45° Dunn radiographs, with alpha angles >55° defined as cam-positive (Figure 1). Measurements were performed 3 separate times by 4 investigators. One-way ANOVA, independent means t-test and Pearson correlation coefficients were calculated, with statistical significance set at p<0.05.ResultsTwenty-six female athletes were included. Average menarchal age was 13.8 ±1.5 years. 24 (92%) had alpha angles >55°; 20 (77%) had bilateral cam deformity. Inter-rater reliability was excellent at 0.86. Intra-rater reliability was also excellent, with mean ICC=0.87 (range= 0.82-0.90 for each rater). There was a significant positive association between age of menarche and alpha angle (p<0.02, Figure 2). There was no association between alpha angle and hip ROM.ConclusionElite female ice hockey players have a higher prevalence of cam morphology than the general population. The positive association between alpha angle and age of menarche supports the etiological hypothesis of the cam lesion resulting from activity-related stress at the proximal femoral physis during a period of physiologic vulnerability. Professional women’s ice hockey players have a high risk of developing cam morphology of the proximal femur, although each player’s age of menarche may mediate her individual risk for cam lesion development.Figure 1.Figure 2.

Youth Developmental Experiences Among Female Hockey Players: The Role of Relative Age

Relative age differences can lead to varying sport participation opportunities; however, scant research has focused on the impact of relative age on experiences within sport. This study explored if youth developmental experiences differed by relative age among competitive female ice hockey players. Players within Ontario (n = 264) completed an online survey that contained the Youth Experience Survey for Sport (YES-S) along with additional demographic questions. The YES-S measures 5 dimensions of positive (i.e., personal and social skills, cognitive skills, goal setting, and initiative) and negative developmental experiences in sport. The results of the multivariate analysis of variance (MANOVA) suggested that the developmental experiences reported by athletes did not differ across birth quartiles (Wilks’ Lambda = 0.940, F (15, 707.105) = 1.061, p = .390). Although there was a relative age effect (RAE) trend within this sample of competitive female ice hockey players, the differences across birth quartiles were not statistically significant. It appears that relative age does not result in youth having different positive and negative sporting experiences. Exploring the characteristics of sport environments (e.g., coaches, practices) and personality traits of competitive athletes to better understand how relatively younger athletes continue their participation in sport despite being at a perceived disadvantage warrants further investigation.

Sweat Loss and Fluid Intake of Female Varsity Ice Hockey Players During On-Ice Practices and Games.

Bigg, JL, Gamble, ASD, Vermeulen, TF, Bigg, LM, and Spriet, LL. Sweat loss and fluid intake of female varsity ice hockey players during on-ice practices and games. J Strength Cond Res 34(2): 389-395, 2020-Sweat losses of ∼1.5-2% body mass (BM) during exercise impairs athletic performance in stop and go sports such as ice hockey. The study examined the pre-exercise hydration status, sweat loss, fluid and carbohydrate (CHO) intake, and sodium balance of female hockey players. Twenty-four female varsity hockey players were tested during 2 practices and 4 games. Data analyses were performed using a level of significance of p ≤ 0.05. Over 70% of players arrived at the practices and ∼50% of players arrived at the game mildly dehydrated. Before the high- (P1) and low-intensity (P2) practices, players consumed an average of 0.19 ± 0.14 and 0.15 ± 0.13 L. Before the games, mean fluid intake was 0.39 ± 0.19 L. The sweat rate during P1 was significantly greater than P2 (p = 0.006), but there was no significant difference in total fluid intake between practices (p = 0.279). Consequently, the average BM loss for P1 was significantly greater than that for P2 (p = 0.016). Sweat loss during games was 1.01 ± 0.29 L and fluid intake was 0.70 ± 0.43 L, resulting in minimal BM losses (<1% BM for all players). CHO intake during games was 39.2 ± 22.8 g, with 19/20 players consuming CHO before or during the intermissions of the game. Sweat sodium losses were 0.64 ± 0.34 and 0.32 ± 0.18 g·h for P1 and P2, and 0.83 ± 0.38 g during the game. In conclusion, female ice hockey players replaced the fluid they lost through sweat during practices and games and maintained adequate hydration. Players also consumed adequate CHO during games from the CHO containing food and drinks provided.

Reliability of the force-velocity-power variables during ice hockey sprint acceleration

ABSTRACT The aims of this study were to ensure that the skating velocity describes a mono-exponential function in order to determine the reliability of radar-derived profiling results from skating sprint accelerations applying sprint running force-velocity assessment approach. Eleven young highly-trained female ice hockey players performed two 40-m skating sprints on two separate days to evaluate inter-trial and test-retest reliability. The velocity-time data recorded by a radar device was used to calculate the kinetics variables of the skating sprint acceleration: maximal theoretical force (F0), maximal theoretical velocity (V0), maximal theoretical power (Pmax) and the slope of the linear force-velocity relationship (SFV). SFV and SFVrel variables (the slope of the linear relationship between horizontal force relative to body mass and velocity) demonstrated ‘low’ to ‘moderate’ intra-class correlation coefficients (ICC). All other variables revealed ‘acceptable’ inter-trial and test-retest reliability (ICC ≥ 0.75 and coefficient of variation [CV] ≤ 10%). Furthermore, test-retest reliability (ICC and CV) and sensitivity [Standard Error of Measurement (SEMs) ≤ Small Worthwhile Change (SWCs)] were higher when averaging the two trials compared to the best trial (40-m split time) only. These findings offer a promising and simple method to monitor training-induced changes in macroscopic mechanical variables of ice hockey skating performance.

Epidemiology of Foot and Ankle Injuries in National Collegiate Athletic Association Men's and Women's Ice Hockey.

Background:Ice hockey is a high-speed contact sport in which athletes are prone to many different injuries. While past studies have examined overall injury rates in ice hockey, foot and ankle injuries among collegiate ice hockey players have yet to be analyzed.Purpose/Hypothesis:The purpose of this study was to elucidate the epidemiology of foot and ankle injuries among collegiate ice hockey players utilizing data from the National Collegiate Athletic Association (NCAA) Injury Surveillance Program. We hypothesized that male ice hockey players would sustain more injuries compared with female ice hockey players and that the injuries sustained would be more severe.Study Design:Descriptive epidemiology study.Methods:Data on all foot and ankle injuries sustained during the academic years 2004 through 2014 were obtained from the NCAA Injury Surveillance Program. Injury rates, rate ratios (RRs), and injury proportion ratios were reported with 95% CIs.Results:Over the study period, the overall rate of foot and ankle injuries for men was higher than that for women (413 vs 103 injuries, respectively; RR, 4.01 [95% CI, 3.23-4.97]). Injury rates were highest during the regular season for both men (358 injuries; RR, 64.78 [95% CI, 58.07-71.49]) and women (89 injuries; RR, 38.37 [95% CI, 30.40-46.35]) compared with the preseason or postseason. The most common injury in men was a foot and/or toe contusion (22.5%), while women most commonly sustained a low ankle sprain (31.1%). For men, foot and/or toe contusions accounted for the most non–time loss (≤24 hours ) and moderate time-loss (2-13 days) injuries, while high ankle sprains accounted for the most severe time-loss (≥14 days) injuries. For women, foot and/or toe contusions accounted for the most non–time loss injuries, low ankle sprains accounted for the most moderate time-loss injuries, and high ankle sprains accounted for the most severe time-loss injuries.Conclusion:Foot and ankle injuries were frequent among collegiate ice hockey players during the period studied. For men, contusions were the most commonly diagnosed injury, although high ankle sprains resulted in the most significant time lost. For women, low ankle sprains were the most common and resulted in the most moderate time lost. These findings may direct future injury prevention and guide improvements in ice skate design.

Seasonal Changes in Physiological Responses and Body Composition During a Competitive Season in Male and Female Elite Collegiate Ice Hockey Players.

Delisle-Houde, P, Reid, RER, Insogna, JA, Chiarlitti, NA, and Andersen, RE. Seasonal changes in physiological responses and body composition during a competitive season in male and female elite collegiate ice hockey players. J Strength Cond Res 33(8): 2162-2169, 2019-Ice hockey continually overloads athletes with limited time for recovery, which may affect several physiological responses and alter body composition. The purpose of this study was to identify changes in physiological parameters and body composition profiles over the competitive season in elite collegiate ice hockey players. Forty-four players, 24 males (age = 22.7 ± 1.3 years, height = 1.82 ± 0.6 m, and body mass = 86.87 ± 6.44 kg) and 20 females (age = 19.9 ± 1.8 years, height = 1.66 ± 0.7 m, and body mass = 68.76 ± 5.91 kg) participated in 4-minute submaximal exercise tests and body composition assessments at pre-season, mid-season, and end-season. Changes in physiological parameters and body composition were analyzed using repeated-measures analysis of covariance controlling for age. Males' postexercise blood lactate concentration decreased (p ≤ 0.05) from pre- to mid-season (9.3 vs. 6.2 mmol·L) and increased (p ≤ 0.05) from mid- to end-season (6.2 vs. 8.0 mmol·L). Heart rate increased (p ≤ 0.05) after the third and fourth minute of the submaximal test in both sexes from pre- to end-season and from mid- to end-season. Males' body fat percentage decreased (p ≤ 0.05) from mid-season (17.4 vs. 16.1%), whereas increases were observed (p ≤ 0.05) in both sexes from mid- to end-season. This study produced evidence that male and female collegiate hockey athletes' physiological responses and body composition profiles change over the season. Sport scientists working with collegiate hockey teams, may need to revise annual training programs to attenuate reductions in fitness and hopefully prevent injuries.

Forefoot and heel take-off strategies result in different distribution of lower extremity work during landings

ABSTRACT Previous research suggests that landing mechanics may be affected by the mechanics of the preceding jump take-off. The purpose of the present study was to investigate whether jump take-off mechanics influence the subsequent landing mechanics. Female volleyball (n = 17) and ice hockey (n = 19) players performed maximal vertical jumps with forefoot and heel take-off strategies. During forefoot and heel jumps, participants were instructed to shift their weight to their forefoot or heel, respectively, and push through this portion of the foot throughout the jump. Jump mechanics were examined using 3D motion analysis, where lower extremity net joint moment (NJM) work, NJM, and segment angles were compared between forefoot and heel jumps using multivariate ANOVA. During jump take-off, participants performed more positive ankle plantar flexor and knee extensor NJM work in forefoot compared to heel jumps (P < 0.05). From initial foot contact to foot flat, participants performed more negative ankle plantar flexor and hip extensor NJM work during heel compared to forefoot jumps (P < 0.05). The present results demonstrate that using a heel take-off strategy results in a different distribution of lower extremity NJM work and NJM during landing compared to landings following forefoot jumps.

On-Ice Measures of External Load in Relation to Match Outcome in Elite Female Ice Hockey.

The aim of this study is to investigate the differences between select on-ice measures using inertial movement sensors based on match outcome, and to determine changes in player movements across three periods of play. Data were collected during one season of competition in elite female ice hockey players (N = 20). Two-factor mixed effects ANOVAs for each skating position were performed to investigate the differences in match outcome, as well as differences in external load measures during the course of a match. For match outcome, there was a small difference for forwards in explosive ratio (p = 0.02, ES = 0.26) and percentage high force strides (p = 0.04, ES = 0.50). When viewed across three periods of a match, moderate differences were found in skating load (p = 0.01, ES = 0.75), explosive efforts (p = 0.04, ES = 0.63), and explosive ratio (p = 0.002, ES = 0.87) for forwards, and in PlayerLoad (p = 0.01, ES = 0.70), explosive efforts (p = 0.04, ES = 0.63), and explosive ratio (p = 0.01, ES = 0.70) for defense. When examining the relevance to match outcome, external load measures associated with intensity appear to be an important factor among forwards. These results may be helpful for coaches and sport scientists when making decisions pertaining to training and competition strategies.

Epidemiology of Female Youth Ice Hockey Injuries Presenting to United States Emergency Department’s from 2007 to 2016

Objectives:Female youth ice hockey players are an overlooked population. No national study has established incidence rates for injuries in female youth ice hockey. The objective of this study was to establish incidence rates by injury location, diagnosis, and mechanism of injury using USA Hockey sanctioned age divisions.Methods:The National Electronic Injury Surveillance System (NEISS) was queried for all ice hockey injuries (product code 1279) from January 1, 2007 to December 31, 2016. Cases involving players over the age of 19 and males were excluded. Each injury’s narrative text field was reviewed to determine mechanism of injury. Data was analyzed using (IBM®, v24). Comparisons of incidence by age were made using student’s two sample t-test with 95% confidence interval. Trend analyses were performed using a linear regression. USA Hockey membership statistics were used to establish population at risk and calculate incidence rates. All incidence rates were reported per 10,000 person-years.Results:A total of 384 patients, representing an estimated 10,398 ice hockey-related injuries, presented to NEISS-participating United States emergency departments. During the study period, female youth ice hockey players increased significantly from 44,678 in 2007 to 57,792 in 2016 (p=3.9x10-5, R-squared=0.89, ß =0.94). The overall number of injuries, however, only slightly increased from 992 in 2007 to 1,042 in 2016 (p=ns). Thus, the incidence rate (IR) of injuries fell from 222.1 to 180.2 during the study period. The most commonly injured body parts were the head (n=3048, IR=554.5), trunk (n=1399, IR=256.4), knee (n=1127, IR=169), shoulder (n=704, IR=153.3) and ankle (n=591, IR=120.2). The most common diagnoses were strain/sprain (n=2002, IR=417.7), contusion (n=1877, IR= 348), internal organ injury (n=1863, IR=320), concussion (n=1112, IR=218) and fracture (n=1255, IR=202). The top mechanisms of injury were player-to-player contact (n= 3016, IR=535), falls (n=2249, IR=380.9), and contact with boards (n=942, IR=165.8). The incidence rate of injuries increased with age; The 0-8, 9-10, 11-12, 13-14, 15-16 and 17-19 age divisions had IR’s of 24, 84, 226, 381, 360, and 750, respectively. The player-to-player mechanism of injury also increased with age. The largest IR gap between ages fell between the 11-12 and 13-14 age groups, similar to what has been observed in male ice hockey studies. Player-to-player contact is the leading mechanism of injury in all age groups except the 0-8 age group. Head injuries increased with age division: 0-8 (n=15, IR=1), 9-10 (n=153, IR=17.4), 11-12 (n=598, IR=67.2), 13-14 (n=885, IR=115.1), 15-16 (n=650, IR=121.6) and 17-19 (n=746, IR=232.2). The two most common diagnoses of head injuries were concussion (36%) and internal organ injury (61%), both of these diagnoses increasing with age. In fact, concussion diagnosis increased significantly between each age group (p<0.01).Conclusion:We established the first collection of injury incidence rates for female ice hockey gleaned from a national database. Though body checking is illegal at all levels of women’s ice hockey, player-to-player contact prevailed as the leading mechanism of injury in all but the 0-8 age division. It was also the leading mechanism for the most common injury sites, including the head. This study laid bare an unspoken but long understood fact of the girl’s game that body checking is common and major contributor to the game’s injury burden.

Characterizing the Prevalence of Cam-Type Hip Impingement in Women’s Professional Ice Hockey Players

Objectives:Participation rates in women’s ice hockey is increasing in North America. Recent studies have demonstrated an increased prevalence of femoroacetabular impingement (FAI) in elite male ice hockey players, yet little is known about hip pathology of players in the National Women’s Hockey League (NWHL). The primary purpose of this study was to determine the prevalence of radiographic FAI in women’s professional ice hockey players. The secondary purpose was to analyze the relationship between the presence of radiographic cam deformity and hip ROM, clinical impingement signs and age of menarche.Methods:In this IRB-approved study, physical examination and demographic data were prospectively collected for 27 NWHL players. Alpha angles were measured on 45-degree Dunn views with an alpha angle >55° defined as cam-positive. Pearson correlations were performed to analyze the relationship between alpha angle and ROM measurements, clinical impingement signs and self-reported age of menarche. Players were grouped into those with and without cam impingement and group differences were assessed using the student’s t-test. Statistical significance was set at p<0.05.Results:Twenty-seven athletes were included in the study. Nineteen of the 27 players (70%) had radiologic evidence of cam-type impingement with alpha angle >55 degrees; 14 players (52%) had bilateral cam deformity. The average age of menarche was 13.9±1.5 years. There was a significant association between age of menarche and right alpha angle (R=0.57, CI [0.16, 0.81], p=0.011), as well as age of menarche and left alpha angle (R=0.48, CI [0.03, 0.77], p=0.039). There was no statistically significant association between alpha angle and any ROM measurement. Additionally, there was no difference in the incidence of clinical impingement for players with or without an alpha angle >55°.Conclusion:This study suggests that elite female ice hockey players have a significantly higher prevalence of cam-type morphology than the general population. The clinical significance of this radiographic finding is uncertain as the majority of these deformities seem to be asymptomatic. Interestingly, the positive association between alpha angle and age of menarche lends support to the etiological hypothesis that cam lesions are a result of activity-related stress at the proximal femoral physis. This data suggests that players with earlier menarche (and therefore earlier physeal closure) seem to be less vulnerable to the development of cam deformity of the proximal femur.

Relationship Between Physiological Off-Ice Testing, On-Ice Skating, and Game Performance in Division I Female Ice Hockey Players.

Boland, M, Delude, K, and Miele, EM. Relationship between physiological off-ice testing, on-ice skating, and game performance in Division I female ice hockey players. J Strength Cond Res 33(6): 1620-1629, 2019-The purpose of this study was to identify off-ice testing variables that correlate with skating and game performance in Division I collegiate female ice hockey players. Twenty female forward and defensive players (19.95 ± 1.35 years) were assessed for mass, height, percent fat mass (%FAT), bone mineral density, predicted 1 repetition maximum (RM) absolute and relative (REL%) bench press (BP) and hex bar deadlift (HDL), lower-body explosive power, anaerobic power, countermovement vertical jump, maximum inspiratory pressure (MIP), and on-ice repeated-skate sprint (RSS) performance. The on-ice RSS test included 6 timed 85.6-m sprints with participants wearing full hockey equipment; fastest time (FT), average time (AT), and fatigue index (FI) for the first length skate (FLS; 10 m) and total length skate (TLS; 85.6 m) were used for analysis. Game performance was evaluated with game statistics: goals, assists, points, plus-minus, and shots on goal (SOG). Correlation coefficients were used to determine relationships. Percent fat mass was positively correlated (p ≤ 0.05) with FLS-FI and TLS-AT; TLS-FT was negatively correlated with REL%HDL; BP-RM was negatively correlated with FLS-FT and FLS-AT; MIP positively correlated with assists, points, and SOG; FLS-AT negatively correlated with assists. Game performance in female ice hockey players may be enhanced by greater MIP, repeat acceleration ability, and mode-specific training. Faster skating times were associated with lower %FAT. Skating performance in female ice hockey players may be enhanced by improving body composition, anaerobic power, and both lower- and upper-body strength in off-ice training.

Lisa S. Krivickas Clinician/Scholar Travel Award: Characterizing the Prevalence of Cam-Type Hip Impingement in Women’s Professional Ice Hockey Players

PURPOSE Recent studies have demonstrated an increased prevalence of femoroacetabular impingement (FAI) in elite men's ice hockey players, yet little is known about the hips of players in the National Women’s Hockey League (NWHL). The primary purpose of this study was to determine the prevalence of radiographic cam-type FAI in women’s professional ice hockey players. The secondary purpose was to analyze the relationship between the presence of cam deformity and hip ROM; clinical impingement signs; and age of menarche. METHODS Clinical, radiographic and demographic data were collected for NWHL players during pre-participation physicals. Alpha angles were measured on 45° Dunn radiographs, with alpha angles >55° defined as cam-positive. Spearman correlations were performed to analyze the relationship between alpha angle and both ROM measurements and menarchal age. Players were grouped into those with and without cam lesions and group differences were assessed using the student's t-test. RESULTS Twenty-seven athletes were included. Nineteen (70%) had alpha angles >55°; 14 (52%) had bilateral cam deformity. Average menarchal age was 13.9 ±1.5 years. There was a significant association between age of menarche and alpha angle (right hips, p=0.01; left hips, p=0.04). There was no significant association between alpha angle and either hip ROM or clinical impingement signs. CONCLUSION This study suggests that elite female ice hockey players have a higher prevalence of cam-type morphology than the general population. The positive association between alpha angle and age of menarche lends additional support to the etiological hypothesis of the cam lesion resulting from activity-related stress at the proximal femoral physis; players with earlier menarche (and therefore earlier physeal closure) seem to be less vulnerable to the development of cam deformity of the proximal femur. Thus, professional women’s ice hockey players have a high risk of developing cam-type morphology of the proximal femur, although each player’s age of menarche may mediate her individual risk for cam lesion development.

Characterizing the Prevalence of Cam-Type Hip Impingement in Women’s Professional Ice Hockey Players

PURPOSE: Recent studies have demonstrated an increased prevalence of femoroacetabular impingement (FAI) in elite men's ice hockey players, yet little is known about the hips of players in the National Women’s Hockey League (NWHL). The primary purpose of this study was to determine the prevalence of radiographic cam-type FAI in women’s professional ice hockey players. The secondary purpose was to analyze the relationship between the presence of cam deformity and hip ROM; clinical impingement signs; and age of menarche. METHODS: Clinical, radiographic and demographic data were collected for NWHL players during pre-participation physicals. Alpha angles were measured on 45° Dunn radiographs, with alpha angles >55° defined as cam-positive. Spearman correlations were performed to analyze the relationship between alpha angle and both ROM measurements and menarchal age. Players were grouped into those with and without cam lesions and group differences were assessed using the student's t-test. RESULTS: Twenty-seven athletes were included. Nineteen (70%) had alpha angles >55°; 14 (52%) had bilateral cam deformity. Average menarchal age was 13.9 ±1.5 years. There was a significant association between age of menarche and alpha angle (right hips, p=0.01; left hips, p=0.04). There was no significant association between alpha angle and either hip ROM or clinical impingement signs. CONCLUSION: This study suggests that elite female ice hockey players have a higher prevalence of cam-type morphology than the general population. The positive association between alpha angle and age of menarche lends additional support to the etiological hypothesis of the cam lesion resulting from activity-related stress at the proximal femoral physis; players with earlier menarche (and therefore earlier physeal closure) seem to be less vulnerable to the development of cam deformity of the proximal femur. Thus, professional women’s ice hockey players have a high risk of developing cam-type morphology of the proximal femur, although each player’s age of menarche may mediate her individual risk for cam lesion development.

Sweat Loss and Hydration Habits of Female Olympic, Varsity and Recreational Ice Hockey Players.

This study measured sweat losses, voluntary fluid intake, sodium balance, and carbohydrate intake of female ice hockey players during on-ice practices at the Olympic, varsity, and recreational levels. Testing was conducted on 25 Canadian Olympic players, 21 varsity, and 21 recreational players. The average sweat rate for the Olympic players (0.99±0.08 L/h) was significantly greater than both the varsity (0.67±0.05 L/h, p=0.001) and the recreational players (0.42±0.03 L/h, p<0.001), and the varsity players also had a significantly greater sweat rate than the recreational athletes (p=0.016). Total fluid intake was significantly greater for both the Olympic (p=0.001) and varsity players (p=0.007) compared to the recreational group. Only 3 of 25 Olympic players lost>1.5% BM and 4 others lost>1% BM, with no players in both the varsity and recreational teams losing>1% BM. Half of the Olympic players consumed some carbohydrate during practice, but most of the varsity and recreational players did not. In conclusion, sweat rates in female ice hockey players during practices were proportional to competitive level. Fluid intake was similar between groups and resulted in only a few athletes at the Olympic level being at risk of excess body mass loss.

Neuromuscular Adaptations to Short-Term High-Intensity Interval Training in Female Ice-Hockey Players.

Kinnunen, J-V, Piitulainen, H, and Piirainen, JM. Neuromuscular adaptations to short-term high-intensity interval training in female ice-hockey players. J Strength Cond Res 33(2): 479-485, 2019-High-intensity interval training (HIIT)-related neuromuscular adaptations, changes in force production, and on-ice performance were investigated in female ice-hockey players during preseason. Fourteen Finnish championship level ice-hockey players (average age 22 ± 3 years) participated in 2½-week HIIT. Both spinal (H-reflex) and supraspinal (V-wave) neuromuscular responses of the soleus muscle were recorded before and after the training period. Static jump (SJ) and countermovement jump heights, plantarflexor maximum voluntary contraction (MVC), and rate of force development (RFD) were measured. In addition, soleus and tibialis anterior muscle activations (electromyography) were measured during MVC and RFD tests. During on-ice training, skating speed and acceleration tests were performed. Subjects significantly improved their plantarflexion MVC force (11.6 ± 11.2%, p < 0.001), RFD (15.2 ± 15.9%, p < 0.01), and SJ (4.8 ± 7.6%, p ≤ 0.05). Voluntary motor drive to the soleus muscle (V-wave amplitude) increased by 16.0 ± 15.4% (p < 0.01), and coactivation of the tibialis anterior muscle during the plantarflexion RFD test was reduced by -18.9 ± 22.2% (p ≤ 0.05). No change was observed in spinal α-motoneuron excitability (H-reflex) during MVC or in on-ice performance. These results indicate that HIIT can be used to improve athletes' capability to produce maximal and explosive forces, likely through enhanced voluntary activation of their muscles and reduced antagonist coactivation. Therefore, HIIT can be recommended in preseason training to improve neuromuscular performance. However, a longer than 2½-week HIIT period is needed to improve on-ice performance in female ice-hockey players.

Grip Strength in Youth Ice Hockey Players: Normative Values and Predictors of Performance.

Toong, T, Wilson, KE, Urban, K, Paniccia, M, Hunt, AW, Keightley, M, and Reed, N. Grip strength in youth ice hockey players: Normative values and predictors of performance. J Strength Cond Res 32(12): 3503-3511, 2018-Grip strength is a simple, valid, and reliable tool for estimating overall muscular strength, a key component of health-related fitness and sport performance. To date, there is a paucity of up-to-date and developmentally sensitive grip strength norms specific to youth-athlete populations. The objectives of this study are to (a) establish normative grip strength values in youth ice hockey players, (b) descriptively compare these values with existing Canadian pediatric norms, and (c) explore the relationship between age, sex, body mass, and hockey playing level on grip strength performance. A sample of 690 male and female youth ice hockey players between the ages of 10 and 16 years were included. Participants completed assessments of maximal grip strength using a hand dynamometer on both hands. In addition, age, sex, body mass, and hockey playing level were collected. Maximal absolute grip strength, stratified by age and sex, was higher than previously published Canadian pediatric norms. Grip strength increased with age in both sexes. Males and females performed similarly until 12 years of age, after which point males had greater strength. Individuals with greater body mass had greater strength. For the nondominant hand, competitive players had greater strength than those playing house league or select. This study describes normative grip strength values in youth ice hockey players according to age, sex, body mass, and playing level. These athlete-specific norms may be used to help evaluate and monitor changes in grip strength over time in youth ice hockey players.

Difference Between Male and Female Ice Hockey Players in Muscle Activity, Timing, and Head Kinematics During Sudden Head Perturbations.

This study examined sex differences in head kinematics and neck muscle activity during sudden head perturbations. Sixteen competitive ice hockey players participated. Three muscles were monitored bilaterally using surface electromyography: sternocleidomastoid, scalene, and splenius capitis. Head and thorax kinematics were measured. Head perturbations were induced by the release of a 1.5-kg weight attached to a wire wrapped around an adjustable pulley secured to the participant's head. Perturbations were delivered in 4 directions (flexion, extension, right lateral bend, and left lateral bend). Muscle onset times, muscle activity, and head kinematics were examined during 3 time periods (2 preperturbation and 1 postperturbation). Females had significantly greater head acceleration during left lateral bend (31.4%, P < .05) and flexion (37.9%, P = .01). Females had faster muscle onset times during flexion (females = 51 ± 11ms; males = 61 ± 10ms; P = .001) and slower onset times during left lateral bend and extension. Females had greater left/right sternocleidomastoid and scalene activity during extension (P = .01), with no difference in head acceleration. No consistent neuromuscular strategy could explain all directional sex differences. Females had greater muscle activity postperturbation during extension, suggesting a neuromuscular response to counter sudden acceleration, possibly explaining the lack of head acceleration differences.

National injury prevention measures in team sports should focus on knee, head, and severe upper limb injuries

PurposeTo examine acute injuries in licensed floorball, football, handball, and ice hockey players in all ages nationwide in Sweden, and to identify the most common and severe injuries in each body location and recommend injury prevention measures.MethodsUsing national sport insurance data from years 2006–2015 was the incidence and proportion of acute injuries, and injuries leading to permanent medical impairment (PMI), calculated in the four team sports. The most common injury type and injured body part was identified, with a particular focus of the severe injuries. Comparison between sexes was made.ResultsIn total, there were 92,162 registered injuries in all sports together. Knee injuries were most common, and also had the highest incidence of PMI, in all ball sports and in female ice hockey players. In male ice hockey, the most common injury was a dental and face injury, and PMI injuries were mostly in the shoulder. The most severe PMI injuries were rare and most often a face/eye injury in male floorball and ice hockey, a concussion in female ice hockey, and a knee injury in female floorball, and in both sexes in football and handball.ConclusionsTo achieve the greatest impact in reducing the adverse effects of acute sport injuries nationwide in Sweden, preventive measures should focus on knee injuries in all the investigated team sports. The severe head/face and upper limb injuries also need attention. Protective equipment, neuromuscular training programs, rules enforcements, and fair-play interventions may reduce the incidence of injuries.