Three-dimensional kinematics of the knee and ankle joints for three consecutive push-offs during ice hockey skating starts

The Impact of an 8-Week Resisted Sprint Training Program on Ice Skating Performance in Male Youth Ice Hockey Players

ABSTRACT

Dietze-Hermosa, MS, Montalvo, S, Gonzalez, MP, and Dorgo, S. The impact of an 8-week, resisted, sprint training program on ice skating performance in male youth ice hockey players. J Strength Cond Res 38(5): 957-965, 2024-The purposes of this randomized control study were to (a) compare the effects of an on-ice versus an overground resisted sprint training intervention and a control condition and (b) identify changes in ice skating kinematics and kinetics after training intervention participation. Twenty-four youth ice hockey players were randomly allocated into 3 groups: (a) on-ice resisted sprint training (on-ice RST); (b) overground resisted sprint training (overground RST); and (c) body weight resistance training (control). During the 8-week intervention, the 2 RST groups engaged in sled towing methods, whereas the control group engaged in a body weight resistance training program twice a week. A series of individual, repeated-measures analysis of variances with post hoc pairwise comparisons were conducted for variables of interest. An interaction effect was noted for ice skating s-cornering agility drill completion time ( p = 0.01; ηp2 = 0.36), ice skating 30-m top speed completion time ( p = 0.04; ηp2 = 0.27), step length ( p = 0.04; ηp2 = 0.26), and knee angle at touchdown ( p = 0.03; ηp2 = 0.30). The on-ice RST group displayed superior improvements across ice skating tests compared with the control group. Data show that on-ice RST has the greatest transfer effect to ice skating metrics; however, improvements in certain ice skating metrics can be observed with overground training also.

Assessment of Three-Dimensional Kinematics of High- and Low-Calibre Hockey Skaters on Synthetic ice Using Wearable Sensors

Hockey skating objective assessment can help coaches detect players’ performance drop early and avoid fatigue-induced injuries. This study aimed to calculate and experimentally validate the 3D angles of lower limb joints of hockey skaters obtained by inertial measurement units and explore the effectiveness of the on-ice distinctive features measured using these wearable sensors in differentiating low- and high-calibre skaters. Twelve able-bodied individuals, six high-calibre and six low-calibre skaters, were recruited to skate forward on a synthetic ice surface. Five IMUs were placed on their dominant leg and pelvis. The 3D lower-limb joint angles were obtained by IMUs and experimentally validated against those obtained by a motion capture system with a maximum root mean square error of 5 deg. Additionally, among twelve joint angle-based distinctive features identified in other on-ice studies, only three were significantly different (p-value < 0.05) between high- and low-calibre skaters in this synthetic ice experiment. This study thus indicated that skating on synthetic ice alters the skating patterns such that the on-ice distinctive features can no longer differentiate between low- and high-calibre skating joint angles. This wearable technology has the potential to help skating coaches keep track of the players’ progress by assessing the skaters’ performance, wheresoever.

What Differences Exist in Professional Ice Hockey Performance Using Virtual Reality (VR) Technology between Professional Hockey Players and Freestyle Wrestlers? (a Pilot Study)

There is little research on the study of specific characteristics that contribute to the faster adaptation of athletes during the transition from one sport to another. We used virtual reality (VR) to study the differences between professional ice hockey players and other sport professionals (freestyle wrestlers), who were novices in hockey in terms of motor responses and efficiency performance, on different levels of difficulty. In the VR environment, four levels of difficulty (four blocks) were simulated, depended on the speed of the puck and the distance to it (Bl1—60–80 km/h and 18 m; Bl2—60–100 km/h, distances 12 and 18 m; Bl3—speeds up to 170 km/h and 6, 12, and 18 m; Bl4—the pucks are presented in a series of two (in sequence with a 1 s interval)). The results of the study showed that the hockey professionals proved to have more stable movement patterns of the knee and hip joints. They also made fewer head movements as a response to stimuli during all runs (0.66 vs. 1.25, p = 0.043). Thus, working out on these parameters can contribute to the faster adaptation of wrestlers in developing professional ice hockey skills.

Lower limb muscle activation patterns in ice-hockey skating and associations with skating speed

In this study, we aimed to describe lower limb kinematic and muscle activation patterns and then to examine the potential associations between those variables and skating speed in highly trained ice-hockey players. Twelve players (age 18.4-22.0 years) performed five maximal 30-metre forward skating sprints. Skating speeds, muscle activities from eight lower limb muscles (gluteus maximus, gluteus medius, adductor magnus, rectus femoris, vastus lateralis, biceps femoris, tibialis anterior and soleus), and sagittal plane joint angles from the hip and knee joint were measured. A lower activity of the gluteus maximus (r = -0.651, p = 0.022, β = -0.08) and a reduced gluteus maximus to rectus femoris coactivity (r = -0.786, p = 0.002, β = -3.26) during the recovery phase were found to be associated with faster skating speed. No significant associations were observed between sagittal plane hip and knee kinematics and skating speed. This study provides evidence that muscle activities during the recovery phase of skating may have an important role in skating performance.

Importance of Joint Angle-Specific Hip Strength for Skating Performance in Semiprofessional Ice Hockey Athletes

ABSTRACT

Secomb, JL, Dascombe, BJ, and Nimphius, S. Importance of joint angle-specific hip strength for skating performance in semiprofessional ice hockey athletes. J Strength Cond Res 35(9): 2599-2603, 2021-Ice hockey athletes with faster sprint acceleration and change-of-direction (COD) skating performance possess a competitive advantage. However, it is unknown whether joint angle-specific hip strength, in combination with measures known to relate to skating performance (e.g., countermovement jump [CMJ]), better explains skating performance. The purpose of this research was to determine whether hip strength in joint angles specific to skating positions and CMJ performance explains sprint skating acceleration and COD performance. Thirteen semiprofessional male hockey (26.7 ± 6.7 years; 88.4 ± 18.1 kg; 181.9 ± 5.4 cm) athletes were assessed for CMJ performance, hip abduction and adduction strength, 10-m sprint skating acceleration, and COD (505) performance. Linear multiple regressions to predict skating acceleration and COD performance were calculated with variables chosen based on functional justification and magnitude of correlation. Hip abductor relative peak force (rPF) at 25° of hip abduction and CMJ rPF explained 46.0% (adjusted) of variance in sprint acceleration performance (F[2,12] = 6.18, p = 0.02). Countermovement jump peak eccentric velocity, adductor rPF at 50° of hip abduction, and difference in abductor rPF between 50° and 25° of hip abduction explained 85.0% (adjusted) of the variance in 505 time (F[3,12] = 22.8, p < 0.001). Hip strength at joint angles functionally relevant to skating (e.g., at 25° and 50°), in combination with relevant CMJ variables, explained large and very large amounts of variance in sprint skating acceleration and COD performance in this cohort. The inclusion of joint angle-specific hip strength profiling to a physical performance testing battery may provide practitioners with more specific knowledge on the strength of the hip through abduction range of motion, which may affect skating performance.

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 (F_0rel), velocity (V₀), power (P_maxrel), slope of the linear relationship between force relative to body mass and velocity (S_FVrel), maximal horizontal component of the ground reaction force to the corresponding resultant force (RF_max) and minimal rate of decrease of this ratio (D_RF). On-ice mechanical capacities (F_0rel, P_maxrel, RF_max and D_RF) largely-to-very largely correlated with 40-m skating split time (r ranging from 0.82 for D_RF to -0.91 for P_maxrel; p < 0.001). Performance variables (SJ height, 30-m running and 40-m forward skating split time) and P_maxrel 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, S_FVrel, D_RF and force-velocity deficit) to very large (P_maxrel) 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.

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

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 (P_max) and the slope of the linear force-velocity relationship (S_FV). S_FV and S_FVrel 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.

Principal component analysis identifies differences in ice hockey skating stride between high- and low-calibre players

The objective was to compare joint angles during full stride skating on ice between high- and low-calibre hockey players. High (n = 8) and low (n = 8) calibre male participants completed full stride skating on ice for two to five trials. A 10-camera motion capture system collected kinematic data. Ankle, knee, and hip angles were calculated. Principal component analysis (PCA) identified important angle characteristics and each trial was scored against principal components (PC-scores). Hierarchical linear models examined relationships between PC-scores and skill level with and without controlling for speed. High-calibre participants were associated with greater ankle inversion during push-off and recovery (p < 0.001), greater knee extension (p = 0.051) and external rotation at push-off (p = 0.038), and greater hip flexion throughout stride (p = 0.027) after controlling for speed. Interactions existed between speed and skill level including faster skating speeds were associated with increased plantarflexion at push-off in low-calibre participants while there was no relationship in high-calibre participants. Skating pattern differences between skill levels provide an indication of ideal joint motion during skating. Players should be encouraged to plantarflex the ankle during push-off, extend and externally rotate the knee during push-off, and increase hip flexion throughout stride.

Interjoint coordination of the lower extremities in short-track speed skating

In short-track speed skating, the three-dimensional kinematics of the lower extremities during the whole skating cycle have not been studied. Kinematic parameters of the lower extremities during skating are presented as joint angles versus time. However, the angle-time presentation is not sufficient to describe the relationship between multi-joint movement patterns. Thus, angle-angle presentations were developed and used to describe interjoint coordination in sport activities. In this study, 15 professional male skaters' full body motion data were recorded using a wearable motion capture system during short-track speed skating. We investigated the three-dimensional kinematics of the lower extremities and then established the interjoint coordination between hip-knee and knee-ankle for both legs during the whole skating cycle. The results demonstrate the relationship between multi-joint movements during different phases of short-track speed skating. This study provides fundamentals of the movement mechanism of the lower extremities that can be integrated with physiotherapy to improve skating posture and prevent injuries from repetitive stress since physiological characteristics play an important role in skating performance.

An on-ice measurement approach to analyse the biomechanics of ice hockey skating

Skating is a fundamental movement in ice hockey; however little research has been conducted within the field of hockey skating biomechanics due to the difficulties of on-ice data collection. In this study a novel on-ice measurement approach was tested for reliability, and subsequently implemented to investigate the forward skating technique, as well as technique differences across skill levels. Nine high caliber (High) and nine low caliber (Low) hockey players performed 30m forward skating trials. A 3D accelerometer was mounted to the right skate for the purpose of stride detection, with the 2nd and 6th strides defined as acceleration and steady-state, respectively. The activity of five lower extremity muscles was recorded using surface electromyography. Biaxial electro-goniometers were used to quantify hip and knee angles, and in-skate plantar force was measured using instrumented insoles. Reliability was assessed with the coefficient of multiple correlation, which demonstrated moderate (r>0.65) to excellent (r>0.95) scores across selected measured variables. Greater plantar-flexor muscle activity and hip extension were evident during acceleration strides, while steady state strides exhibited greater knee extensor activity and hip abduction range of motion (p<0.05). High caliber exhibited greater hip range of motion and forefoot force application (p<0.05). The successful implementation of this on-ice mobile measurement approach offers potential for athlete monitoring, biofeedback and training advice.

Predictors of Speed Using Off-Ice Measures of College Hockey Players

The purpose of this study was to examine the relationship between commonly employed dry-land performance tests and skating speed in male collegiate ice hockey players. Forty male National Collegiate Athletic Association Division I hockey players were tested on the following performance variables: vertical jump (VJ), standing broad jump, 40-yard dash, and maximal back squat (SQT). The subjects also performed 3 skating tests: the 90-ft forward acceleration test, the 90-ft backward acceleration test, and the 50-ft flying top speed test (F50). Pearson correlation coefficients were applied to compare the strength of association between each selected off-ice measure and each on-ice measure. Three multiple regression equations were then used to compare the weighted strengths of association between predictor and criterion variables. Only VJ showed significance in relation to skating speed (p = 0.011). These results suggest that meaningful performance testing in ice hockey players should occur mainly on the ice.