Within-athlete weekly sRPE loads were highly variable for both playing standards; however, representative level athletes participated in significantly more activity outside of school compared with nonrepresentative athletes during November-December (effect size; 0.43-club technical training; 0.36-club matches), January-February (effect size; 0.78-club technical training; 0.75-club matches), and February-March (effect size; 0.63-club technical training; 0.44-club matches). Therefore, club and school coaches must ensure that all elements of representative athletes training schedules are coordinated and flexible to promote positive adaptions to training such as skill and physical development and prevent maladaptive responses such as overuse injury and nonfunctional overreaching. A cooperative and malleable training schedule between club/school coaches and the athlete will allow the athlete to perform on multiple fronts while also being able to meet the demands of additional stressors such as schoolwork.Case, MJ, Knudson, DV, and Downey, DL. Barbell squat relative strength as an identifier for lower extremity injury in collegiate athletes. J Strength Cond Res XX(X) 000-000, 2020-The aim of the study was to determine the efficacy of using the relative strength level of Division I athletes in One repetition maximum (1RM) barbell back squat as an identifier of seasonal lower extremity (LE) injury. One repetition maximum back squat (kg) and reported LE injuries were retrospectively collected for Division I male football (n = 46), female volleyball and softball athletes (n = 25). Maximum preseason relative (body mass normalized) back squat strength values were compared with 2 analyses of variance (p less then 0.05) between injured and uninjured male (football) and female athletes (softball & volleyball). Relative back squat strength was significantly lower in injured athletes than uninjured athletes in both men (F = 6.03, p = 0.02) and women (F = 4.68, p = 0.04) with a moderate to large effect size (g = 0.86-0.85). These data indicate the potential of 1RM back squat relative strength serving as one tool in multi-factor preseason screening for LE injury risk in these sports. Male athletes with relative squat strength below 2.2 and female athletes below 1.6 in these sports could be more susceptible to LE injury over a season. Strength professionals should consider using body mass normalized 1RM back squats as a screening tool for seasonal LE injury risk in college athletes.Dinyer, TK, Byrd, MT, Succi, PJ, and Bergstrom, HC. The time course of changes in neuromuscular responses during the performance of leg extension repetitions to failure below and above critical resistance in women. J Strength Cond Res XX(X) 000-000, 2020-Critical resistance (CR) is the highest sustainable resistance that can be completed for an extended number of repetitions. Exercise performed below (CR-15%) and above (CR+15%) CR may represent 2 distinct intensities that demonstrate separate mechanisms of fatigue. Electromyography (EMG) and mechanomyography (MMG) have been used to examine the mechanism of fatigue during resistance exercise. Therefore, the purposes of this study were to (a) compare the patterns of responses and time course of changes in neuromuscular parameters (EMG and MMG amplitude [AMP] and mean power frequency [MPF]) during the performance of repetitions to failure at CR-15% and CR+15% and (b) identify the motor unit activation strategy that best describes the fatigue-induced changes in the EMG and MMG signals at CR-15% and CR+15%. Ten women completed one repetition maximum (1RM) testing and repetitions to failure at 50, 60, 70, and 80% 1RM (to determine CR), and at CR-15% and CR+15% on the leg extension. During all visits, EMG and MMG signals were measured from the vastus lateralis. There were similar patterns of responses in the neuromuscular parameters, and time-dependent changes in EMG AMP and EMG MPF, but not MMG AMP or MMG MPF, during resistance exercise performed at CR-15% and CR+15% (p less then 0.05). The onset of fatigue occurred earlier for EMG AMP, but later for EMG MPF, during repetitions performed at CR+15% compared with those performed at CR-15%. Thus, resistance exercise performed below and above CR represented 2 distinct intensities that were defined by different neuromuscular fatigue mechanisms but followed similar motor unit activation strategies.Worcester, KS, Baker, PA, and Bollinger, LM. Effects of inertial load on sagittal plane kinematics of the lower extremity during flywheel-based squats. J Strength Cond Res XX(X) 000-000, 2020-Increasing load increases flexion of lower extremity joints during weighted squats; however, the effects of inertial load on lower extremity kinematics during flywheel-based resistance training (FRT) squats remain unclear. The purpose of this study was to evaluate sagittal plane kinematics of lower extremity joints during FRT squats at various inertial loads. Nine recreationally resistance-trained subjects (3M, 6F) completed a bout of FRT squats with inertial loads of 0.050, 0.075, and 0.100 kg·m. https://www.selleckchem.com/products/tecovirimat.html Two-dimensional sagittal plane kinematics were monitored with retroreflective markers at a rate of 60 Hz. Joint angles and angular velocities of the knee, trunk + hip, trunk inclination, and ankle were quantified throughout concentric and eccentric actions. Effects of inertial load were determined by repeated-measures analysis of variance with α = 0.05. Average power and average vertical velocity decreased with increasing inertial load, whereas average force increased. Minimal and maximal sagittal plane joint angles of the knee, trunk + hip, trunk inclination, and ankle were not significantly different among inertial loads. However, peak joint angular velocities of the knee and trunk + hip tended to decrease with increasing inertial load. Conversely trunk inclination and ankle dorsiflexion velocities were not significantly different among inertial loads. Increasing inertial load from 0.050 to 0.100 kg·m significantly reduces average power during FRT squats primarily by decreasing movement velocity, which seems to be specific to the knee and hip joints. It is possible that lower concentric energy input at high inertial loads prevents increased joint flexion during FRT squats.