Browsing by Author "Jordan, Matthew J."

Now showing 1 - 7 of 7
  • Thumbnail Image
    ItemOpen Access
    An Intervention Program Designed to Improve Balance and Power in U14 Alpine Ski-Racers
    (2018-09-20) Kashluba, Kayla Amanda; Doyle-Baker, Patricia Katherine; Clark, Marcia L.; Emery, Carolyn A.; Jordan, Matthew J.; Westin, Maria
    Purpose: To investigate if a neuromuscular training (NMT) warm-up program during preseason improved lower limb balance and maximal muscular power compared to a standard preseason program in alpine ski-racers 10-13-years-old (U14) after 8-weeks. Methods: Quasi-experimental study design. Participants included n=73 skiers from five Alberta Alpine Ski Association (AASA) ski-clubs. Ski-clubs in the intervention group (n=3) completed 2 15-min coach-delivered NMT warm-ups a week, while the standard of care (SOC) (n=2) ski-clubs completed their standard training; NMT warm-up program included balance, strength, and agility exercises. Performance outcome measures completed at baseline and post –testing included: vertical jump (VJ), star excursion balance test (SEBT) reach distances, and predicted VO2max. Results: Participants in the intervention group demonstrated significant improvements on the VJ and SEBT. Conclusions: Dynamic balance and peak leg power improved post implementation of the NMT warm-up program in U14 alpine ski-racers.
  • Thumbnail Image
    ItemOpen Access
    Change of Direction Movement Evaluation in Soccer-Specific Environment with Inertial Measurement Units: Guiding Practice and Test Tasks in Youth Soccer
    (2023-06-02) Alanen, Aki-Matti; Pasanen, Kati; Benson, Lauren C.; Jordan, Matthew J.; Ferber, Reed
    Soccer players perform a multitude of change of direction (COD) movements while playing. This multiplanar movement has been related to both performance and injury-risk in previous studies. However, traditional testing of COD ability has been done with preplanned protocols that lack the aspect of perception and reaction and commonly use only running time as the main variable. Therefore, the main objectives of this thesis were to explore novel methods of COD testing with the use of inertial measurement units (IMUs) in both preplanned soccer-specific tests and during game-play. The results of Chapter Three suggest that neither peak resultant acceleration (PRA) nor peak angular velocity (PAV) is a reliable metric in final foot contact (FFC) analysis of 180° pivot turns. The intra-class correlations (ICC) for pivot turns on both sides were unacceptable. However, when separating females and males it was found that the reliability in female participants was significantly better. In Chapter Four, the in-season variability of PRA was found to be different between previously injured players and injury free players, specifically during the FFC of 180° pivot turns. Chapter Five expanded upon the game-specific demands on COD movements based on playing positions. Significant differences in volume and types of CODs by playing position were found, which raises the question if youth soccer player testing for multiplanar movement abilities, should consider specific playing position related demands better in the future. Chapter Six complemented the studies by providing results of measurements obtained with IMUs in relation to situational patterns during game-play. The findings indicated that running speed, COD angle, pressure from opposing player, and contact with another player prior or during the cut would increase the acceleration during the COD, thus increasing the demands of the neuromuscular system. In conclusion, following one or two specific metrics at single timepoints to analyze COD ability is not recommended. Future research should search for methods involving perception-reaction while performing COD and these could be complemented with wearable technology measures. The combinations of multiple variables could be used to follow-up fluctuations of player performance through a longer follow-up period.
  • Thumbnail Image
    ItemOpen Access
    Feasibility, reliability and concurrent validity of a field test of exertion in high school students
    (2019-07-02) Miutz, Lauren Nicole; Schneider, Kathryn J.; Emery, Carolyn A.; Jordan, Matthew J.; Black, Amanda M.
    Study Design: Test-retest reliability and concurrent validation study. Background: Exertional testing is an important component of a multifaceted assessment following concussion, however the literature evaluating a non-laboratory field test of exertion is limited. Objectives: 1) To evaluate the feasibility of a field test of aerobic capacity (modified shuttle run test - mSRT), 2) to examine the test-retest reliability of the mSRT, and 3) to evaluate the concurrent validity of a mSRT compared to the Buffalo Concussion Treadmill Test (BCTT) in uninjured high school students. Methods: Sixty uninjured adolescent males enrolled in high school sports performance courses (age 15-16 years) completed the mSRT twice (one week apart) and the BCTT once. Heart rate (HR) utilizing a Polar HR monitor, self-reported rating of perceived exertion (RPE), and overall symptoms were assessed. Results: The mSRT was feasible in high school students, with 95% of participants (n=57) completing all three testing sessions and no adverse events reported. The mSRT had a moderate level (ICC=0.68) of test-retest reliability. The mean difference between peak heart rates on the mSRT1 and BCTT was -2.62 (95% CI -7.14, 1.91). Median HRpeak (187 bpm), RPEpeak (18), and stage achieved (23) was highest following the BCTT. Fatigue or low energy was the most commonly reported symptom following all three testing sessions. Conclusions: This study found that there were similar responses to BCTT and mSRT in uninjured adolescent male participants. Further research to better understand the reliability and concurrent validity in a more heterogeneous sample, including female participants and participants following concussion, is warranted.
  • Thumbnail Image
    ItemOpen Access
    High-Performance Coaches Attitudes and Beliefs Regarding Technology Adoption
    (2020-01-21) Jaswal, Ramandeep Singh; Katz, Larry; Jordan, Matthew J.; Paskevich, David M.
    Technological innovation has been shown to make meaningful impacts on many aspects of high-performance sport. Although the literature on technology adoption and implementation is vast, currently very little literature exists on the coach’s perspective in this regard. Further, when looking at Canadian high-performance coaches specifically, the results yield even less information. This investigation measured antecedents of technology adoption using validated forms. Further, this investigation explored the thematic categories of inter-organizational trust, subjective norms/social influence, and with regard to their relationship to technology adoption among Canadian high-performance coaches. Eleven coaches from both summer and winter National Sport Organizations (NSOs) were interviewed in a semi-structured format. Five thematic categories were identified (three from the literature and two from the thematic analysis). Results for inter-organization trust showed that these coaches valued being aware and informed of any planned changes, and educating coaches on technology adoption was essential in order to gain coaches’ participation. With respect to subjective norms and social influence, many of these high-performance coaches stated that they depended on mentor coaches or other coaches in the field to identify new technology. To this end, they also received support from other organizations and teams. Regarding technological proficiency, it was found that these coaches appreciated technology that specifically addressed their pain points and valued collaboration among various stakeholders in the Canadian sporting space concerning learning about technology and being educated on its use. The final two themes include how these coaches viewed the advantages of employing technology, and what challenges they faced when it comes to finding and using new technology.
  • Thumbnail Image
    ItemOpen Access
    Neuromuscular Deficits Following Anterior Cruciate Ligament Reconstruction with Hamstring Autograft: Implications for Rehabilitation and Return to Sport Testing
    (2020-07-16) Morris, Nathaniel; Herzog, Walter; Jordan, Matthew J.; Doyle-Baker, Patricia K.; Heard, Mark
    The purpose of this study was to analyse the effects of anterior cruciate ligament reconstruction (ACLR) using the semitendinosus (ST) tendon autograft technique on knee flexor maximal torque, rate of torque development (RTD) and electromechanical delay (EMD) in athletes who had returned to competition, and to determine the relationship between knee flexor strength deficits and hamstring muscle cross-sectional area (CSA). Athletes with ACLR and non-injured, sex-matched, and sport-matched control athletes performed maximal voluntary contractions (MVC) of isometric knee flexion and extension to obtain maximal torque (TorqueMax) and maximal RTD (RTDMax) at 30°, 50°, 70°, 90° and 105° of knee flexion. Ultrasound imaging was used to measure muscle CSA of the knee flexors at 25%, 50%, and 75% of the anatomical distance from the knee crease to the ischial tuberosity. Deficits were found at all knee joint angles for Torquemax and more than 70° of knee flexion for knee flexor RTDmax when comparing the ACLR limb to the Contralateral limb. ST muscle CSA was smaller in the ACLR limb compared to the Contralateral limb at all measurement sites and strong to very strong correlations (r=0.6-0.9) were found between ST muscle CSA and knee flexor strength, especially for the distal ST CSA measurement site. No differences in EMD were found across joint angles, and no differences in ST EMD were found between limbs. The EMD was significantly elongated in the lateral hamstring muscles of the ACLR limb. These results suggest the importance of assessing and preserving ST muscle architecture following ACLR as well as restoring BF mechanical properties. Furthermore, graft choice should be made with consideration of the effect of ACLR on the torque-joint angle relationship and the specific strength requirements of the athlete’s sport.
  • No Thumbnail Available
    ItemOpen Access
    Nonlocalized postactivation performance enhancement (PAPE) effects in trained athletes: a pilot study
    (Applied Physiology Nutrition and Metabolism, 2017-10) Cuenca-Fernández, Francisco; Smith, Ian Curtis; Jordan, Matthew J.; MacIntosh, Brian R.; López-Contreras, Gracia; Arellano, Raúl; Herzog, Walter
    Fifteen trained athletes were assessed for postactivation performance enhancement (PAPE) of squat jumps (SJs) and power push-ups (PPUs) following upper body activation, lower body activation, upper and lower body activation, and rest. SJ improved similarly across all 4 conditions. PPU could not be assessed. Since the test protocol of SJ and PPU involved upper and lower body activation and caused PAPE in SJ, future work is required to determine if a nonlocalized PAPE effect exists.
  • Thumbnail Image
    ItemOpen Access
    The Effects of Force-Velocity Test Specificity on On-Ice Acceleration Performance Prediction in Elite Speed Skaters
    (2024-01-10) Zukowski, Matthew; Jordan, Matthew J.; Herzog, Walter; Edwards, Brent; MacInnis, Martin
    This primary purpose of this thesis was to investigate the influence of off-ice force-velocity test specificity on the prediction of on-ice acceleration performance in elite long track speed skaters. We assessed a functional force-velocity relationship using three loaded jump protocols. In the first study, we established the intra-day reliability of two novel unilateral loaded jump protocols, the single leg horizontal (JumpHorz) and lateral (JumpLat) jumps. These protocols were shown to be reliable, displaying significant interrelationships with on-ice sprint race split times at distances of 100 m, 400 m, and 500 m. The second study validated an exponential function model to evaluate velocity changes during an on-ice sprint start that provided a more detailed assessment of on-ice acceleration capacity compared to the convention of split times. The exponential model allowed for the calculation of performance parameters, which demonstrated strong reliability, and differentiation between elite and sub-elite athletes. In the final study, we compared the JumpLat, JumpHorz and CMJ loaded jump tests for the prediction of on-ice acceleration performance obtained from our exponential model. Using a regularized regression model, we found that the loading condition is more significant than movement specificity for predicting on-ice acceleration performance. In summary, these studies provide practitioners in skating sports with novel off and on-ice testing methodology that may be used to better monitor performance during the running and gliding phases on-ice, and to inform individualized training prescription.