Botter, A, Cross, MR, Da Lozzo, G, Floreani, M, Samozino, P, Morin, J-B, and Rejc, E. Volume-equated high-load resisted-sprint training: determining the longitudinal effects of varying distance and repetitions on acceleration performance in rugby players. J Strength Cond Res 39(8): 823–828, 2025—Understanding how to precisely program resisted sprinting to enhance sprint phase-based adaptations is an important yet underexplored topic. This pilot study examined the impact of high-load sled-resisted sprint training when varying distance and repetitions for the same overall volume on acceleration capabilities and performance. Twenty under-19 national-level rugby players were divided into 2 groups, performing sprint sets of short or long distances over an 8-week intervention. Resistance (∼50% individual maximal velocity decrement, through load-velocity profiling) and overall volume (distance × repetitions) were equated across groups. Preintervention and postintervention testing included 10, 20, and 30 m split times, and acceleration-speed profiles to characterize maximal acceleration and speed capacities. The main effects of group, time, and their interaction were assessed using linear mixed-effects models, with the athletes as random effects, and subsequent analyses of variance. Statistically significant large mean effects were observed across for 10 m split times, maximal theoretical acceleration, and the slope of the acceleration-speed profile (omega-squared = 0.19–0.34, p 0.05). The findings align with existing research suggesting that high-load resisted sprinting specifically enhances acceleration capabilities. The absence of clear differences in training outcomes between the groups may be attributed to the similarity of stimuli, indicating a need for greater variation in volume distribution (e.g., increased distances per repetition) to discern effects. However, our results imply that acceleration performance improvements might be less sensitive to volume distribution variations than expected, allowing practitioners flexibility in their programming within this study's parameters. 
Bounias, T, Henry, G, Goswami, R, Moran, J, Behm, DG, and Drury, B. Effects of Nordic hamstring exercise set configuration on eccentric hamstring strength changes in youth female athletes. J Strength Cond Res 39(8): 829–836, 2025—Anterior cruciate ligament injury poses a significant risk in youth female athletes. The Nordic hamstring exercise (NHE) can improve eccentric hamstring strength (EHS), a key factor related to anterior cruciate ligament injury risk, yet limited research exists in this population. This study compared 2 NHE set configurations—traditional sets (TS) and rest redistribution (RR)—on EHS in youth female athletes. Subjects (age: 13.93 ± 1.58 years; body mass: 48.95 kg ± 11.15 kg; percentage of predicted adult height: 96.50% ± 4.30%) were randomly assigned to TS (n = 17) or RR (n = 18) groups. Both groups performed a 6-week NHE program, increasing weekly volume from 6 to 18 repetitions. Pretests and post-tests assessed EHS changes using the NordBord and isokinetic testing at 60°·s−1 and 180°·s−1, assessing peak torque (PT), angle of peak torque (°PT), and torque at 20°, 40°, 60°, and 80° of knee flexion. Both TS and RR significantly increased NordBord EHS (g = 0.34–0.98). Isokinetic data at 60°·s−1 and 180°·s−1 revealed significant small increases in PT and torque at 40°, 60°, and 80° (g = 0.22–0.46). Yet, no changes were observed in torque at 20° (g = 0.01–0.23) and the °PT increased (g = 0.33–0.83). No between-group differences were observed for any measure. These findings suggest that TS or RR set configurations can effectively enhance EHS in youth female athletes. However, to target EHS at longer muscle lengths, practitioners should include additional exercises beyond the NHE. 
Trask, BF, Montgomery, TR Jr, Honea, C, Remotigue, EB, Sears, KN, Hammer, SM, and Dinyer-McNeely, TK. Increasing eccentric proportion of repetitions leads to increased time to task failure. J Strength Cond Res 39(8): 837–844, 2025—This study examined the effect of altered concentric (CON) and eccentric (ECC) phases of a repetition on repetitions completed, performance fatigability, electromyographic (EMG) amplitude (AMP), and mean power frequency (MPF), and muscle oxygen saturation (SAT). Subjects (n = 23) performed fatiguing, single-limb leg extension at 40% 1 repetition maximum at 3 cadences: 3sCON,1sECC (3C:1E), 1sCON, 3sECC (1C:3E), 2sCON, 2sECC (2C:2E). A 1-way (cadence: 1C:3E, 3C:1E, 2C:2E) repeated-measures ANOVA examined differences in repetitions completed and performance fatigability (%Δ pre–post exercise maximal voluntary isometric contraction force). Separate 2 (phase: CON, ECC) × 3 (cadence: 1C:3E, 3C:1E, 2C:2E) repeated-measures ANOVAs examined differences in %Δ for EMG AMP, EMG MPF, and SAT . Significance was set at p 
Leitão, L, Pareja-Blanco, F, Marinho, D, and Neiva, H. Effects of different back squat protocols on prefrontal cortex oxygenation responses. J Strength Cond Res 39(8): 845–849, 2025—The prefrontal cortex (PFC) plays an important role in the execution of the various motor tasks that an athlete performs because the brain is involved in the process of starting and ending every exercise. However, the cerebral oxygenation responses to resistance exercise until muscle failure induced by distinct loads are unclear. Therefore, we examined the PFC oxygenation responses to different loads in the back squat exercise. Eighteen men (4.3 ± 1.4 years of experience, 28.1 ± 3.8 years, 74.8 ± 8.8 kg, 1.78 ± 0.05 m, 14.9 ± 3.9% body fat) performed 3 back squat protocols to task failure with distinct loading conditions: 3, 6, and 10RM. Prefrontal cortex oxygenation (oxygenated-HbO2 and deoxygenated-HHb hemoglobin; total hemoglobin-tHb; and tissue oxygenation index-TOI) was analyzed during the protocols by near-infrared spectroscopy. HbO2 and tHb increased throughout the protocols for all loading conditions (p 
McDowell, K, Long, A, Chae, S, Nelson, A, Goode, N, Lis, R, Mizuguchi, S, Baur, M, Duca, M, Wagle, JP, Fry, AC, Daniel, G, and Stone, MH. Comparison of strength development in traditional set-rep configuration vs. accentuated eccentric loading training over a 4-week strength-endurance block. J Strength Cond Res 39(8): 850–856, 2025—This study investigated the chronic effects of accentuated eccentric loading (AEL) paired with cluster sets (CS) on strength. Seventeen (11 men and 6 women) recreationally active subjects (23.18 ± 4.15 years, 1.72 ± 0.1 m, 81.29 ± 22.18 kg) were randomly assigned to AEL (n = 9) and traditional (TRAD) (n = 8) groups. During 4 weeks of training, AEL group performed 3 sets of (5 × 2) repetitions of back squat and bench press using weight releasers and CS, whereas TRAD group performed the same total sets and reps and exercises using traditional loading and set structures. Dynamic (back squat and bench press 1 repetition maximum [1RM]) and isometric (midthigh pull peak force and rate of force development) strength were tested before and after training and analyzed using a 2-way analysis of variance. There was a main effect of time for back squat 1RM (p = 0.008; 125.0 ± 42.4–131.0 ± 42.2 kg) and back squat + bench press 1RM (p = 0.02; 213.0 ± 74.6–220.0 ± 75.3 kg). No significant interaction effects were observed in any variables posttraining (p > 0.05). Although the isometric rate of force development decreased in both groups, TRAD showed a shaper decline than AEL after training (−20.57% [g = −0.33] vs. −0.93% [g = −0.01]). The benefit of AEL paired with CS in maximum dynamic strength may not outweigh its logistical burden. However, practitioners may consider this method in maintaining the isometric rate of force development during high-volume training. 
Vatne, E, Merrigan, JJ, Stone, JD, Saenz, C, Kraemer, WJ, and Hagen, JA. Effects of daytime floatation-restricted environmental stimulation therapy on nocturnal cardiovascular physiology, sleep, and subjective recovery in collegiate student-athletes: A comprehensive observational study. J Strength Cond Res 39(8): 857–867, 2025—The primary aim of this study was to explore the relationship between floatation-restricted environmental stimulation therapy (floatation-REST) and nocturnal cardiovascular physiology and sleep in collegiate athletes. The secondary aim was to describe the perceived changes in soreness, mood, fatigue, energy level, and overall experience after floatation-REST in collegiate athletes. Data included 214 records of nocturnal cardiovascular physiology and sleep collected using an acceptably valid and reliable wearable device (Ōura Ring, Ōura Health, Oulu, Finland) from 97 athletes (52.57% women) on 12 varsity teams, and 2,319 survey responses collected immediately after floatation-REST from 898 athletes (48.88% women) on 36 varsity teams. Nocturnal cardiovascular physiology was assessed through resting heart rate, heart rate variability, and respiration rate, while sleep was summarized using total sleep time, time in bed, and sleep efficiency. The representation of teams was varied, with football and men's and women's swimming heavily represented. Male and female athletes were analyzed separately to prevent overlooking sex-specific physiologic differences. Resting heart rate was significantly lower after floatation-REST than at night immediately before the session in female athletes (p 
Joniak, KE, Moore, SR, Ladan, AN, Cantu, EI, Britton, ME, and Smith-Ryan, AE. Custom regional segmental lower limb lean soft tissue analysis in male and female Division I athletes. J Strength Cond Res 39(8): 868–874, 2025—Asymmetries in lean soft tissue (LST) may affect athlete availability and injury risk. Segmental custom regions of interest (C-ROI) analyses may reveal LST differences that could go undetected by whole limb analysis using dual energy x-ray absorptiometry (DXA). The purpose of the study was to describe a novel C-ROI LST segmental analysis method using DXA, and to characterize asymmetry across the sample and identify meaningful difference cut points for C-ROI segmental analyses in elite athletes. Full-body DXA testing was performed on 581 NCAA Division I athletes (46% female, mean ± SD; Age = 20.2 ± 1.4 years, mass = 83.3 ± 26.0 kg) from August 2015 to July 2023. Custom regions of interest analyses were completed for glute, thigh, and calf segments on each leg. Regional percent differences ([segment LST difference]/[total segment LST/2] × 100) were calculated and meaningful differences were established from mean and standard deviations between limbs of each segment. The C-ROI method demonstrated high inter-reliability at each segment (intraclass correlation coefficient: 0.874–0.999). Average LST segmental limb differences for male athletes were (mean ± SD): glute = 1.4 ± 4.4%, thigh = 0.3 ± 2.9%, calf = 0.6 ± 4.7%; and for female athletes: glute = 2.0 ± 4.4%, thigh = 0.3 ± 4.2%, calf = 0.8 ± 4.6%. Values >2 standard deviations for male athletes (glute: 10.2%, thigh: 6.1%, calf: 9.9%) and female athletes (glute: 10.9%, thigh: 8.6%, calf: 10.0%) seemed to be clinically meaningful. Using meaningful regional difference cut points may provide staff (i.e., athletic trainers, dietitians, and strength coaches) insight into acceptable LST asymmetries to better support athlete performance and return to play. 
Pinzone, AG, Abu-Amara, Y, Gant, RW, Rivera, J, Tagesen, EC, Barkley, JE, and Jajtner, AR. The relationship between relative rest and team performance across competitive seasons in the National Football League. J Strength Cond Res 39(8): 875–879, 2025—This investigation aimed to assess the relationship between relative rest index (RRI) and team performance across multiple seasons of National Football League (NFL) competition. To examine this relationship, all NFL regular season games from the 1970–71 to 2022–23 NFL seasons (N = 12,290) were analyzed with rest intervals calculated for each team on a game-to-game basis as the number of days between current and previous games. Next, RRI was calculated as the discrepancy in rest intervals between competing teams for all games and averaged for all teams across all seasons with teams categorized by season average RRI (0.70). Win percentage and playoff depth (lost in wild card round; lost in divisional round; lost in conference championship; lost in Super Bowl; won Super Bowl; did not make playoffs) quantified team performance. Pearson product correlations were implemented to assess the relationship between season average RRI and win percentage. One-way analyses of variance assessed differences in win percentage across RRI categories and RRI across playoff depth categories. A trivial negative correlation between RRI and win percentage across all seasons was noted. Moreover, win percentage did not differ across RRI categories, while RRI was attenuated among teams that lost in the Super Bowl and divisional round compared with teams that did not qualify for the playoffs, suggesting that RRI has no significant effect on team performance with competitive eras of NFL competition collated. 
Oláh, V, Třebický, V, Maleček, J, Michalička, V, Wąsik, J, and Vágner, M. Is countermovement jump height and one repetition maximum back squat associated with the peak force of a front kick with and without carried load? J Strength Cond Res 39(8): 880–889, 2025—The front kick is a fundamental technique used in self-defense and hand to hand combat. This study aimed to test whether front kick performance, both with and without a 30-kg carried load, can be effectively estimated or tracked through commonly available testing procedures such as the countermovement jumps (CMJ) and one repetition maximum back squat (1RM BS). In 2 testing sessions, 21 male participants (mean age = 22.7 years, SD = 1.9) performed 1RM BS, 5 front kicks peak force (FK) without and with 30-kg carried load (FK30), and 3 CMJ without and with 30-kg carried load (CMJ30). A force plate measured the peak force (N) of the FK and FK30 and the height (cm) of the CMJ and CMJ30. Statistically significant correlations were found between CMJ and FK (r = 0.55 [0.225–1], p = 0.005) and CMJ and 1RM BS (r = 0.54 [0.219–1, p = 0.005]). Carried load reduced both CMJ height by 61% (d = 3.35 [2.543–∞], p 
Peveler, WW, Schoffstall, J, Kilian, J, Glauser, J, Coots, J, and Peveler, R. The effects of mixed martial arts gloves on grip strength in trained fighters. J Strength Cond Res 39(8): 890–892, 2025—Grip strength is a key component during grappling segments of a mixed martial arts (MMA) competition. Gloves are worn during MMA competitions to reduce damage to the striker and the opponent during contact. Fighters often complain that MMA gloves reduce the ability to grip an opponent effectively. However, the reported decrease in grip strength has yet to be examined. The purpose of this study was to determine the effects of mixed martial arts gloves on grip strength. Fourteen trained fighters volunteered to participate in this study. Grip strength was measured using a hand grip strength dynamometer during 2 counterbalanced trials (1 with an MMA glove and 1 without). Grip strength was measured 3 times during each trial, with 1 minute of recovery between each attempt. The highest recorded grip strength was used for each condition. Means for dependent measures (highest grip strength for both conditions) were compared using a paired sample t-test with an alpha of 0.05. Grip strength was significantly greater in the no glove condition (46.21 ± 6.14 kg) than in the glove condition (35.57 ± 6.12 kg) at p ≤ 0.001, d = −3.09. Findings from this study indicate that MMA gloves significantly decrease grip strength by 23% in relation to the no glove condition. This reduction in strength could be significant enough to result in a decrease in the ability of the fighter to control an opponent's movement. Fighters should spend more training time grappling in MMA gloves, and MMA glove redesign should be considered. 
Johnson, AL, Kokott, W, Dziuk, C, and Cross, JA. Assessment of muscular fatigue on hip and torso biomechanics in adolescent baseball pitchers. J Strength Cond Res 39(8): 893–899, 2025—Muscular fatigue is an injury risk indicator, and its effect on pitching biomechanics warrants investigation. This study evaluated hip and torso biomechanics to measure muscular fatigue after a limited number of pitches thrown. We hypothesized that postpitching tests would reveal reduced stride length and hip and torso strength, altering hip and torso kinematics and increasing throwing arm kinetics. Adolescent male baseball pitchers' hip and abdominal oblique strength were measured before and after a short pitching session. Pitching biomechanics were calculated from pitches within the first 5 and last 5 of a single throwing session. Means and standard deviations were calculated, and a linear regression model examined the relationships between total number of pitches and dependent variables, with significance level of p ≤ 0.05. Seventeen adolescent male baseball pitchers (age: 17.1 ± 1.0 years, height: 183.9 ± 7.1 cm, mass: 82.9 ± 10.3 kg) completed an average 35 pitches. Significant decreases were found for torso rotation angle and body separation angle at ball release, along with decreased timing of maximum shoulder internal rotation velocity. Strength measurements significantly decreased for back hip extension, lead hip extension, back hip external rotation, lead hip external rotation, and lead hip internal rotation. The linear regression model showed 3 significant observations: body separation angle at foot contact, body separation angle at ball release, and peak pelvis rotation velocity. Scatter plots demonstrated a bimodal distribution between 35 and 40 pitches, with more variability at higher pitch counts. Significant changes in pre- and postpitching tests highlight the impact of muscular fatigue, demonstrating areas for targeted strength training in adolescent baseball pitchers. 
Eserhaut, DA, Fry, AC, Stone, MH, and Kraemer, WJ. Acute endocrine responses with long-term weightlifting in a 51-year-old male weightlifter. J Strength Cond Res 39(8): 900–907, 2025—To study the effects of long-term (>35 years) competitive weightlifting on acute endocrine activity, a 51-year-old male two-time Olympian in weightlifting (Subject A) was compared with highly trained young male weightlifters (controls, n = 23; age = 17.7 ± 0.3 years). Between 1400 and 1700 hours, subjects performed 15 maximum effort vertical jumps, a series of single repetitions of the snatch progressing to a maximal effort, and 3 × 10 snatch pulls at 60% 1 repetition maximum. Blood sampling occurred at 0700 hours, pre-exercise, and +5 and +15 minutes postexercise. Exercise performances were comparable between Subject A and controls and elicited similar lactate responses at +5 minutes (mmol·L−1; A = 9.2; controls = 8.1 ± 0.4). Resting testosterone at 0700 hours was lower for Subject A than for the controls (nmol·L−1; A = 13.9; controls = 25.4 ± 2.0), although acute responses at +5 minutes were comparable (A = 21.6; controls 18.3 ± 1.5). Cortisol responses (nmol·L−1; A = 468.4, controls = 540.6 ± 32.3) and testosterone:cortisol ratio (A = 0.0461; controls = 0.0376 ± 0.004) were similar at +5 minutes. Subject A showed no 22 kDa growth hormone response at +5 minutes, while controls exhibited a substantial increase (µg·L−1; A = 0.4; controls = 16.7 ± 2.6). β-endorphin responses were no different at +15 minutes for Subject A relative to controls (pmol·L−1; A = 30.1; controls = 33.8 ± 3.7). Resting and exercise-induced endocrine physiology is partially modified with aging despite long-term participation in competitive weightlifting. Importantly, Subject A's testosterone response was largely preserved. 
Mitchinson, CJ, Kwak, M, Succi, PJ, Benitez, B, and Bergstrom, HC. Polyphenol-rich sorghum bicolor extract enhances strength recovery after eccentric exercise. J Strength Cond Res 39(8): e951–e959, 2025—This randomized, double-blind, placebo (PL) controlled trial examined the effects of a polyphenol-rich supplement on muscular strength recovery after eccentric exercise. Twenty-nine men (mean ± SD, age = 23.1 ± 3.8 years) were randomly assigned to a high- (500 mg·d−1; n = 9) or low- (250 mg·d−1; n = 10) dose polyphenol-rich sorghum bicolor extract, or PL (n = 10) group and completed a 17- to 18-day supplementation period, with eccentric exercise on day 14 + 1. Unilateral forearm flexion strength, muscle thickness (MT), pain pressure threshold (PPT), perceived recovery, and pain ratings were recorded before (baseline) and at 24, 48, and 72 hours after maximal eccentric exercise. Analyses included mixed-model ANCOVAs, ANOVAs, and post hoc Bonferroni corrected pairwise comparisons (p 
Zhang, Y, Ou, M, Cheng, M, Ying, X, Hu, H, and Korivi, M. Effects of moderate-intensity resistance training on vascular endothelial function and arterial stiffness in young healthy men. J Strength Cond Res 39(8): e960–e966, 2025—This study aimed to ascertain the effects of moderate-intensity resistance exercise (RE) training on arterial stiffness (AS) and endothelial function (EF) in healthy young men. Thirty-two young male adults were randomly assigned to RE and control groups. The RE group performed moderate-intensity (65% 1 repetition maximum) RE training sessions 3 times a week for 8 weeks, while the control group maintained their usual lifestyle without any exercise intervention. Heart rate (HR), blood pressure (BP), flow-mediated dilation (FMD), brachial-ankle pulse wave velocity (baPWV), and carotid-femoral pulse wave velocity (cfPWV) were measured before and after the intervention. The results showed that time and group had large interaction effects on arterial resting diameter (p = 0.020, η2p = 0.168) and FMD (p = 0.017, η2p = 0.175), but not on maximum diameter, HR, or BP. Compared with baseline, resting diameter increased (p 
Kim, YK, Lee, HB, and Lee, SH. Trends in mean hand grip strength, cutoff value, and prevalence of low hand grip strength: An analysis of 2014–2019 Korea National Health and Nutrition Examination Survey (KNHANES) data. J Strength Cond Res 39(8): e967–e973, 2025—The European Working Group on Sarcopenia in Older People 2 (EWGSOP2) defines probable sarcopenia as low muscle strength detected by hand grip strength (HGS). According to this guideline, cutoff for low HGS is determined using a T-score of −2.5 based on age group showing the highest HGS (aged 30–39 years). Our hypothesis is that temporal changes in mean HGS of Koreans may lead to changes in the cutoff values for low HGS and the prevalence of probable sarcopenia as defined by the EWGSOP2 guidelines. We analyzed trends of HGS using 6 years of Korea National Health and Nutrition Examination Survey data. We used the EWGSOP2 guidelines to set yearly cutoff values for low HGS and calculated the prevalence of low HGS. The cutoff value for low HGS and the prevalence rate of low HGS in individuals aged 70 years or older were analyzed using linear regression and trend analysis. We observed a significant decreasing trend from 2014 to 2019 in annual cutoff values for low HGS, ranging from 24.5 to 30.9 kg in men and 13.1–17.3 kg in women. Correspondingly, the prevalence of low HGS (probable sarcopenia) varied significantly from 10.4 to 34.2% in men and 9.1–20.8% in women, indicating notable year-to-year fluctuations (p 
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