MUSCLE ACTIVATION PATTERNS DURING AN ICE HOCKEY SLAP SHOT

The ability to shoot the puck with maximum velocity and accuracy is one of the key components to optimal hockey performance. Of the many types of shots in hockey, the most powerful is the slap shot. A successful slap shot requires a combination of strength, speed, precise timing, and the proper stick choice (Pearsall et aI., 2000; Fergenbaum et aI., 2004). The slap shot consists of four key events -start, top of swing, impact and end. The muscle activation patterns during each of these phases are essential in designing training programs to improve shot velocity (Pan et aI., 1998) and may vary as a function of skill level (Woo, 2004). As such, the purpose of this study was to use three-dimensional kinematics and electromyography (EMG) to conduct a preliminary analysis of the muscle activation patterns during each phase of the slap shot in male, recreational and elite hockey players

DYNAMIC PRESSURE MEASUREMENT ABOUT THE FOOT AND ANKLE

Measures about the foot and ankle within footwear are required to assess the full dynamic interaction. To address this, piezo resistive fabric sensors provide accurate pressure measurement that can be applied within the narrow confines of the footwear-to-footlankle interface. An example of this has been shown in studies focusing on ice hockey skate boots during forward skating. Sixteen flexible piezo-resistive sensors (1.2 cm x 1.8 cm x 0.2 cm thick, FSA Verg Inc.,Canada) were taped to discrete anatomical surfaces of the plantar foot, dorsal foot, the posterior aspect of heel and leg, medial aspect of foot, and lateral aspect of the foot. The results showed an increase in pressure during the stance phase of gait at each anatomical surface with a reciprocal decrease in pressure during swing

A MYOELECTRIC COMPARISON OF TREADMILL AND ICE SKATING

Due to technical and logistic difficulties in conducting skating research on the ice rink surface, the skating treadmill is an excellent resource from a diagnostic and industrial perspective. However; the potential benefits of the skating treadmill hinge on the similarity of treadmill and ice skating parameters. The purpose of this study was to compare the two myoelectric profiles with regards to both temporal and amplitude measures. The findings show that despite intratester, and intersubject variability and differences in stride rate and velocity, the respective myoelectric profiles of the quadriceps and lower leg show strong similarities further indicating a specificity of conditions and gross motor function between conditions

ANKLE KINEMATICS DURING FORWARD HOCKEY SKATING: ACCELERATION TO CONSTANT VELOCITY

Kinematic measures of the foot and ankle are of relevance to footwear manufacturers and to rehabilitative professionals. Difficulties undertaking such measurements have been summarized previously (Milani & Hennig, 2000). This paper presents the kinematic profile of the ankle in both sagittal (plantar dorsi) and frontal (inversion eversion) planes. Penny & Giles electrogoniometers (Blackwood, UK / Biometrics Ltd.) collected data from 5 elite subjects at 1000 Hz. Similar kinematic profiles were observed between 3 accelerating strides and constant velocity strides. Despite the absence of significant differences between strides there was a trend for increased range of motion at the ankle as the skaters accelerated to a high velocity

THE EFFECT OF ACCLIMATIZATION TO THE SKATING TREADMILL

The development of the skating treadmill has enabled researchers to investigate the movement patterns of the forward power skating stride in a controlled environment. It has the potential to aid not only researchers but also coaches, traineJs and therapists leading to an end result of improving the overall performance of the athletes themselves. Studies have investigated biomechanical and physiological parameters of forward skating on the skating treadmill. Turcotte et al. (2004) compared plantar forces distribution patterns of on-ice skating to treadmill skating and discovered significantly elevated levels at heel strike. Hinrich (1994) performed a study comparing on/oH muscle activation patterns and concluded that the skating treadmill accurately replicates on-ice skating. Both these studies failed to use a familiarization period to allow the subjects to acclimatize themselves to skating on the polyethylene tiles. Nobes et al. (2003) did use three, thirty minute bouts to allow for acclimatization and noted differences in submaximal V02, HR and stride rate when treadmill skating was compared to on-ice skating. It is unknown if an acclimatization period has an effect on biomechanical or physiological parameters. Thus, the purpose of this study is to determine whether an acclimatization period has eHects on 02 consumption, muscle activation pattems and kinematics

THE ICE HOCKEY SLAP SHOT, ELITE VERSUS RECREATIONAL

Stationary ice hockey slap shots performed by five elite and five recreational players were compared. Each hockey player performed 5 shots. Three-dimensional kinematics of the stick and upper body were recorded using an electromagnetic tracking device, the Ultratrak®, (Polhemus Inc., Burlington, VT, USA). Joint centers were calculated using the sphere fitting method. Elite players shot significantly faster than recreational players (29.14 ± 1.39 m/s and 26.46 ± 0.66 m/s). Velocity due to translation movement was greater for recreational players compared to novice players (13.14 m/s and 908 m/s). Investigation in maximal angular velocities of the body movement sequences indicated that elite players' maximal velocities moved from the core to the extremities where as recreational players exhibited no such pattern. The results of this study suggested that there are differences in technique when performing the stationary slap shot which may contribute to the increased performance of the ice hockey slap shot

QUANTIFYING FIT IN ICE HOCKEY SKATE BOOTS

Skates are specifically designed for the hockey game context. It is vital that skates be chosen in relation with proper size and shape, as well as with respect to play style and position (Pearsall et al. 2000). To provide optimal function, they must "fit". Fit infers many traits: to fit snugly around the contours of the bony ankle and foot structures, to provide stability, and to avoid discomfort. Nonetheless, players have often sacrificed "fit for comfort" at the expense of "fit for performance". Comfort and fit are interrelated qualities and important factors for footwear in recreational and physical activities. Increasing interest in footwear comfort resulted in several investigations that associated comfort with plantar pressure distribution (Chen et al.1994). To date, improved ratings for shoes comfort can be done by adding a control condition to the testing protocol and using a visual analog scale (VAS) to assess comfort (Mundermann et al. 2002). Little have been done in assessing fit in ice hockey boots. The purpose of this study is to quantify fit in the ice hockey skate boots by means of pressure distribution measures in conjunction with perceptual VAS ratings

KINEMATIC COMPARISONS BETWEEN FORWARD AND BACKWARD SKATING IN ICE HOCKEY

The purpose of this study was to examine the kinematics of lower body and trunk between forward and backward skating. Seven male collegiate ice hockey players skated both forward and backward (C-cut) four times each. A standard two-dimensional kinematic analysis was conducted to examine the lower body extremity and trunk at the instants of weight acceptance and propulsion. No significant differences in the joint angles were found at the weight acceptance. At the propulsion, significant differences were found in the joint angles of hip, knee, ankle and trunk between forward and backward skating. Hence, these findings indicate the importance of strengthing lower body joints and trunk, particularly for forward skating. Future studies are warranted to examine the mechanics of forward and backward skating using a 3D analysis