Merrigan, JJ, Tufano, JJ, and Jones, MT. Potentiating effects of accentuated eccentric loading are dependent upon relative strength. J Strength Cond Res 35(5) 1208-1216, 2021-The purpose was to evaluate the acute effects of accentuated eccentric loading (AEL) on bench press velocity and subsequent perceived effort (ratings of perceived exertion [RPE]) and soreness. Resistance-trained men (n = 8) and women (n = 2) completed 4 sets of 5 bench press repetitions with AEL and traditional loading (TL) using concentric loads of 50% (AEL50, TL50) and 65% (AEL65, TL65) 1-repetition maximum (1RM). Throughout each TL set, the eccentric load remained identical to the concentric. Variable resistance during the first repetition of AEL equaled 120% 1RM. Hierarchical Linear Modeling was used to evaluate differences between AEL and TL (p < 0.05). For the first repetition, AEL50 and AEL65 resulted in slower eccentric and concentric velocities. The increasing slope of eccentric and concentric velocity across repetitions wan 0.05). As an individual's strength increased, AEL50 resulted in slower eccentric velocity and faster concentric velocity than TL50. The AEL65 resulted in faster concentric velocity than TL65 (p less then 0.05). Mean protocol comparisons revealed trivial to small effects between AEL and TL. There were no differences in RPE or soreness between protocols with soreness ratings remaining unchanged from baseline (1.80 ± 0.20 AU; p less then 0.05). Overall, AEL was not effective for increasing concentric velocity during the bench press with current loading protocols. Yet, stronger individuals may exhibit increases in concentric velocity from AEL, which may be a result of different pacing strategies employed during the eccentric phase.  https://www.selleckchem.com/products/capsazepine.html  Furthermore, when using the current AEL protocols, eccentric intensities were increased with no greater RPE or soreness.
  Dos'Santos, T, Thomas, C, Comfort, P, and Jones, PA. Biomechanical effects of a 6-week change of direction speed and technique modification intervention implications for change of direction side step performance. J Strength Cond Res XX(X) 000-000, 2020-The aim of this study was to evaluate the biomechanical effects of change of direction (COD) speed and technique modification training on COD performance (completion time, ground contact time [GCT], and exit velocity) during 45° (CUT45) and 90° (CUT90) side step cutting. A nonrandomized, controlled 6-week intervention study was administrated. Fifteen male, multidirectional, sport athletes (age, 23.5 ± 5.2 years; height, 1.80 ± 0.05 m; mass, 81.6 ± 11.4 kg) formed the intervention group (IG) who participated in two 30-minute COD speed and technique modification sessions per week, whereas 12 male, multidirectional, sport athletes (age, 22.2 ± 5.0 years; height, 1.76 ± 0.08 m; mass, 72.7 ± 12.4 kg) formed the control group (CG) and continued their normal traininncreased propulsive forces over shorter GCTs, and decreased knee flexion. Change of direction speed and technique modification is a simple, effective training method requiring minimal equipment that can enhance COD performance, which practitioners should consider incorporating into their pitch- or court-based training programs.
  Radnor, JM, Oliver, JL, Waugh, CM, Myer, GD, and Lloyd, RS. Muscle Architecture and Maturation Influence Sprint and Jump Ability in Young Boys A Multistudy Approach. J Strength Cond Res XX(X) 000-000, 2020-This series of experiments examined the influence of medial gastrocnemius (GM) and vastus lateralis (VL) muscle architecture (muscle thickness, pennation angle, and fascicle length) on sprint and jump performance in pre-, circa-, and post-peak height velocity (PHV) boys. In experiment 1, 1-way analysis of variance and Cohen's d effect sizes demonstrated that most muscle architecture measures were significantly greater in post-PHV compared with pre-PHV boys (d = 0.77-1.41; p < 0.05). For most sprint and jump variables, there were small to moderate differences between pre-PHV to circa-PHV and circa-PHV to post-PHV groups (d = 0.58-0.93; p < 0.05) and moderate to large differences between pre-PHV and post-PHV groups (d = 1.01-1.47; p < 0.05). Pearson's correlation analyses in experiment 2 determined0.05), with strongest associations within the post-PHV cohort. Chi-squared analyses in experiment 3 identified that, over 18 months, more POST-POST responders than expected made positive changes in GM and VL muscle thickness. Significantly more PRE-POST subjects than expected displayed changes in maximal sprint speed, while significantly more POST-POST individuals than expected showed positive changes in jump height. Muscle architecture seems to be larger in more mature boys compared with their less mature peers and likely underlies their greater performance in sprinting and jumping tasks. Boys experiencing, or having experienced, PHV make the largest increases in muscle architecture and sprinting and jumping performance when tracked over 18 months.
  Marko, D, Bahenský, P, Snarr, RL, and Malátová, R. V[Combining Dot Above]O2peak Comparison of a treadmill vs. cycling protocol in elite teenage competitive runners, cyclists, and swimmers. J Strength Cond Res XX(X) 000-000, 2021-The purpose of this study was to compare the cardiorespiratory and metabolic responses of a maximal graded exercise test (GXT) on a treadmill and cycle ergometer in elite-level, youth competitive athletes. Thirty-one athletes (11 distance runners, 11 mountain-bike cyclists, and 9 long-distance swimmers) were randomly selected to complete either a running or cycling GXT on the first day, followed by the alternative 72 hours apart. The initial work rate for each GXT was set at 50% of the individuals' previously established V[Combining Dot Above]O2peak to elicit fatigue within 8-12 minutes. For the treadmill protocol, speed was increased by 1 km·h-1 each minute, with a constant 5% grade, until volitional fatigue. Cycle ergometer work rate was increased by 30 W every minute until volitimaintain proper cadence (i.e., 100 ± 5 rev·min-1). Throughout both testing sessions, V[Combining Dot Above]O2peak, heart rate [HR] peak, breathing frequency (BF), tidal volume (VT), and minute ventilation (VE) were assessed and used to compare within-sport differences. Runners displayed a higher V[Combining Dot Above]O2peak (∼7%; d = 0.92), HRpeak (4%; d = 0.77), VE (6%; d = 0.66), and BF (12%; d = 0.62) on the treadmill vs. cycle. However, the cycling group demonstrated a greater V[Combining Dot Above]O2peak (∼8%; d = 0.92), VT (∼14%; d = 0.99), and VE (∼9%; d = 0.78) on the cycle, despite no change in HRpeak. For swimmers, the treadmill GXT elicited higher values in V[Combining Dot Above]O2peak (∼5%; d = 0.75), BF (∼11.5%; d = 0.78), and HRpeak (3%; d = 0.69). Collectively, these findings indicate that exercise mode may greatly affect physiological outcome variables and should be considered before exercise prescription and athletic monitoring.