ECSS Paris 2023: CP-AP13
INTRODUCTION: Optimal training for aerobic endurance sports is based on a planned program that specifies load in each session and variations between micro and macrocycles that align with the concept of periodisation (Bull et al., 2001). Although adherence to training has been studied (Santos et al., 2023) it is usually measured as proportion of sessions in a program that were completed, rather than the proportion of each session. This more precise measure of adherence is unknown triathlon (Clemente-Suárez et al., 2021). The current study aimed to quantify adherence to planned training load in age-group triathletes. METHODS: Data representing all training sessions over 6 months from 37 triathletes were analysed (4,040 sessions in total). Adherence was based on the percentage difference between planned training and actual training, for total duration and total distance in each session. Adherence was calculated as mean bias and root mean squared error. RESULTS: Triathletes completed less training than planned (duration; mean bias –5.4 %, rmse 18.9%, and distance; mean bias –1.3%, rmse 16.9%). Focussing on training duration, adherence was not different (p=0.56) between females (mean bias –7.1 %, rmse 15.8%) and males (mean bias –5.1 %, rmse 19.3%) and not different (p=0.40) between the younger (<= 39 years, mean bias –12.0%) and older age categories (>=40 years, mean bias -0.7 to -8.3%). Adherence to planned training duration not different (p=0.94) between athletes that race both Long and Short course (mean bias -7.9%) compared to those that race only Long (-4.9%) or only Short course (-5.2%). Adherence was also not different (p=0.42) in athletes who were coached (mean bias –4.7%) compared to those who were not (-6.6%). CONCLUSION: There are small differences in adherence to planned training that are not statistically significant, but they may be practically important. The imperfect adherence reported here represents the equivalent of 3-5 weeks of missed training per year. Furthermore, the large rmse’s represent the magnitude of both over and under training, which may undermine important variations in training load between different phases of a program. Coaches should monitor and manage adherence carefully as targeted periodisation objectives may not be achieved, leading to sub-optimal adaptations. References Bull, S., Stimmel, B., Veeraraghavan, V., Dynes, R. & Knox, J. Adherence Issues in Sport and Exercise; Wiley: Hoboken, NJ, USA, 2001. Santos, A., ... & Jung, M. E. (2023). Rates of compliance and adherence to high-intensity interval training: a systematic review and Meta-analyses. Int J Behav Nutr & Phys Activity, 20(1), 134. Clemente-Suárez, V. J., … & Batalha, N. (2021). The Effect of Periodization on Training Program Adherence. Int J Enviro Res & Public Hlth, 18(24), 12973.
Read CV Dan DwyerECSS Paris 2023: CP-AP13
INTRODUCTION: Despite the last OGs and a recent interest for cutting-edge training, surfers and equipment manufacturers dont have any tool guarantying them a consistent board-athlete match, mostly due to the incapacity to control the mechanical behavior of the board (McCagh 2013). The aim of this research is to develop a tool and gather data about the boards mechanical behavior to help define the factors of the performance match. It is proposed to make an instrumented surfboard, measuring its rigid-body motions and deformations, synchronized with biometric data from an instrumented surfer. METHODS: A Wyve surfboard is made with a built-in electronic system made of 5 strain-gauges, IMU (Inertial Measure Unit), Bluetooth (BT) communication governed by an Arduino Nano v3. It measures and acquires at 15hz, communicates at 50Hz. The board is calibrated on a 3-points static bending bench with tunable value and position of the input force. Data is calibrated with the inversion method (Kern 2002). Torsion is calibrated with the same method. A surfer is surfing this board in oceanic waves from 0.8 to 1.5m. The experiment lasts for 10min or until 2 waves caught, repeated 5 times (Lestrade 2016). The surfer is instrumented with EMGs (Electromyograph) (Cometa MiniWave Infinity) at a sample rate of 2000Hz. SENIAM references are followed to place the electrodes after skin preparation. The muscles activity (Trapezius Descendens (upper), Triceps brachii, Biceps femoris, Gastrocnemius Medialis) were recorded (Ruess 2013). The legs and lower body position was measured with IMUs (Cometa WaveTrack) calibrated using standing T-pose (Cordillet 2019). RESULTS: On the 3-point bending bench, the system gives the application point positions and force value with this precisions: 1% in x (longwise), 13% in y (in width) and 13.5% in F (force value). In-situ, the surfboard shows good qualitative data in bending. However, due to the ever-changing limit conditions on the nose, bending calibration is irrelevant. Torsion-wise, data was calibrable. It shows that the tail tilts toward the heel of the surfer when he is standing up. On a trimming phase, the tilt-angle is around 0.4°, near 0° during a frontside bottom turn, around 0.5° during the top turn, up to 0.8° during some turns (for an intermediate surfer). About physiognomy, we have the following proportion of the cited-before muscles activity (%), considering a wave being the phases: Paddling (2.4s) 33%. Take-off (0.5s) 12%. Trimming (2.2s) 20%. Bottom turn (0.5s) 6%, Top turn (0.8s) 9% and finish (1s) 20%. CONCLUSION: An instrumented surfboard has been made. It shows interest in measuring the tail torsion in-situ. Further methods will be tested. A physiognomic protocol has been validated and tests with different stiffness boards and pro-athlete will follow.
Read CV Paul-Elie CharlesECSS Paris 2023: CP-AP13
INTRODUCTION: Hamstring injuries are a common and significant problem for athletes. The Nordic Hamstring Exercise (NHE) has been shown to reduce hamstring injury risk, but its application is limited when athletes lack the knee flexor eccentric torque needed to perform NHEs through the full range of motion, leading to extensive muscle damage that hinders subsequent athletic performance. The purpose of this study was to test the efficacy of a novel adaptive resistance training machine (Akuis Sintesi, Italy) in assisting the NHE to enhance its effectiveness as a training intervention. METHODS: The study was approved by the Research Ethics and Governance Committee and participants signed informed consent. Sixteen participants were randomized into assisted-NHE or non-assisted NHE groups to complete 15 NHE repetitions. Assessments before NHE included maximal voluntary knee flexion isometric torque (MVC) and biomechanical analysis of NHE using the Noraxon Portable lab, integrating electromyography (EMG) of bicep femoris and semitendinosus, knee and hip goniometry, shoulder and trunk accelerometery, ankle force and 2D videos. Assessments were repeated 48h later. Sintesi partially off-loaded body mass in the assisted-NHE group via a chest harness, proportional to the athlete’s anthropometry, body mass and strength. Two-way repeated measures ANOVA was used for group and time interactions, with significance set at p<0.05. RESULTS: Assisted-NHE resulted in a greater range of motion (P<0.05), with similar peak EMG and ankle force compared to non-assisted. Assisted NHE had lower muscle soreness at 48h and better preservation of MVC (both p<0.05). CONCLUSION: The Sintesi machine can enhance the effectiveness of NHE by allowing greater range of motion and reducing muscle soreness and damage. This has applications for optimising hamstring training and rehabilitation.
Read CV Patrick MuirheadECSS Paris 2023: CP-AP13