Journal of Strength and Conditioning Research最新文献

Abstract: Rebelo, A, Comfort, P, Harry, JR, and Ripley, N. Drop landing as a neuromuscular fatigue assessment: A submaximal alternative to traditional monitoring methods. J Strength Cond Res 40(1): e17-e25, 2026-Neuromuscular fatigue monitoring is important for optimizing performance and reducing injury risk in elite athletes and tactical personnel. Traditional assessments-such as the countermovement jump (CMJ) or the isometric mid-thigh pull-require maximal effort, which may be inconsistent because of motivation, external constraints, or strategic load management. As an alternative, drop landing emphasizes eccentric control and can be performed submaximally, potentially reducing variability associated with effort while still providing insight into neuromuscular fatigue. The aim of this study was to examine whether fall height, landing phase duration, landing performance index, and average impact force can indicate post-training neuromuscular fatigue in elite volleyball players. Fourteen players (age: 29.18 ± 6.24 years; height: 1.95 ± 0.08 m; body mass: 95.20 ± 7.83 kg) performed drop landings at 70, 85, and 100% of their maximal CMJ height before and after an 82-minute volleyball training session. Test-retest reliability was strong (intraclass correlation coefficient = 0.71-0.98, 95% CI; CV < 6%). Post-training, fall height decreased at 100% ( g = 0.31, p = 0.003), while landing phase duration increased at 100% ( g = 0.55, p = 0.015). Average impact force declined at all drop heights, with significant reductions at 85% ( g = 0.34, p = 0.004) and 100% ( g = 0.35, p = 0.042), suggesting a more softer landing strategy. Landing performance index decreased at 85% ( g = 0.40, p = 0.019) and 100% ( g = 0.58, p = 0.002). These results suggest fatigue-induced changes in force attenuation strategies. Future research should examine whether similar adaptations occur between the landing phase of a maximal CMJ and a 100% drop landing under fatigue.

Abstract: Jagim, AR, Dobbs, WC, Horswill, CA, Twohey, E, Fields, JB, and Jones, MT. Prevalence and magnitude weight loss among collegiate wrestlers. J Strength Cond Res 40(1): 90-97, 2026-The purpose of this study was to examine the percentage of wrestlers who compete in their minimal weight class (MWC), and the magnitude of weight loss. Data from the 2023-2024 collegiate season were retrospectively analyzed resulting in a sample of 9,638 collegiate male wrestlers from the National Association of Intercollegiate Athletics ( n = 1,904) and all 3 divisions of the National Collegiate Athletics Association ( n = 7,734). All wrestlers completed skinfold assessments for weight certification at the start of the competition season. The lowest recorded weight class (LRW) achieved by each wrestler during the season was also recorded and used to determine magnitude of weight loss. Out of the 4,605 (53.2%) of wrestlers who competed in their MWC, their average amount of weight loss was significantly higher than those who did not compete in their MWC (3.9 ± 2.5 vs. 3.2 ± 2.9 kg.; p < 0.001), yet they had an initial lower body fat percentage (12.7 ± 2.9 vs. 17.5 ± 4.8%; p < 0.001). At the time of weight certification, wrestlers weighed 8.1 ± 4.5 (95% confidence interval (CI): 8.0-8.2; effect size (ES) = 1.8) kg more than their minimal wrestling weight. The LRW was 3.6 ± 2.9 (95% CI: 3.6-3.7; ES = 1.2) kg lower than their weight at the time of weight certification. Given that slightly more than half of the male wrestlers competed in their MWC, coaches and sports practitioners should recognize that not all athletes follow the traditional assumption of cutting to the lowest possible weight class. Importantly, those who did achieve their MWC had lower initial body fat percentages, limiting the amount of weight they could safely lose. This underscores the need for individualized weight management strategies that consider body composition and health implications.

Abstract: McCall, CH, Handlery, K, Stock, MS, and Handlery, R. Exercise professionals' strength training attitudes, behaviors, and knowledge: A survey. J Strength Cond Res 40(1): 24-38, 2026-Strength training is frequently used by various professionals, yet little is known about their attitudes, behaviors, and knowledge concerning strength training. An anonymous survey incorporating items on strength training attitudes, behaviors, and knowledge was distributed online (i.e., social media, email, listservs) and responded to by 1,298 exercise professionals (68 athletic trainers, 171 personal trainers, 23 exercise physiologists, 780 physical therapists, 35 physical therapist assistants, 78 strength and conditioning coaches, 87 faculty members, and 56 others). Attitudes and behaviors were compared among professions using Pearson's chi-squared test; average knowledge scores were compared through 1-way analysis of variance. A binary logistic regression (cutoff score = ≥70%) was used to determine how demographics, attitudes, and behaviors affected knowledge scores. Alpha was set at 0.01 for all comparisons. Sixty-eight percent of physical therapists felt that strength training is inadequately applied in their profession compared with 11% of strength coaches. Strength coaches (73.1%) and personal trainers (65.5%) were the most likely professions to document rest periods. Compared with physical therapists, personal trainers and strength coaches were less likely to score ≥70% on knowledge items (OR = 0.22, 99% confidence interval [CI] 0.06-0.79 and OR = 0.21, 99% CI, 0.06-0.80), respectively. Having a Certified Strength & Conditioning Specialist certification increased the odds of scoring ≥70% (OR = 2.47, 99% CI, 1.46-4.16). Exercise professionals have similar attitudes, behaviors, and knowledge of strength training, with a few important exceptions. Results can be used to guide conversations between professions with the goal of improving strength training implementation.

Abstract: Rebelo, A, Lum, D, Ripley, N, and Comfort, P. Evaluating the relationship between single-leg isometric squat and single-leg countermovement jump performance in elite and world-class artistic roller skaters. J Strength Cond Res 40(1): e62-e68, 2026-Lower-limb strength and jump ability are key performance components in artistic roller skating, where athletes perform complex unilateral movements requiring both maximal force and rapid force production. The aim of this study was to evaluate the reliability and practical utility of the single-leg isometric squat for assessing force production and its relationship with performance in the single-leg countermovement jump among elite and world-class artistic roller skaters. Thirty-seven athletes (16 males, 21 females; overall: 17.1 ± 2.6 years, 167.1 ± 10.7 cm, 57.7 ± 10.4 kg; males: 17.5 ± 2.7 years, 175.6 ± 8.3 cm, 64.8 ± 9.5 kg; females: 16.8 ± 2.5 years, 160.6 ± 7.1 cm, 52.4 ± 7.6 kg) performed single-leg isometric squats and single-leg countermovement jumps. Peak force and relative peak force in the single-leg isometric squat demonstrated excellent reliability for both legs (intraclass correlation coefficient [ICC] = 0.96-0.98, coefficient of variation [CV] = 2.56-3.07%), while force at 100 and 200 ms showed moderate-to-good reliability (ICC = 0.82-0.93, CV = 3.88-9.94%). For the single-leg countermovement jump, jump height exhibited excellent reliability (ICC = 0.97-0.98, CV = 5.20-6.44%), while relative propulsive mean force and impulse had moderate-to-good reliability (ICC = 0.83-0.94). Moderate correlations were observed between force at 100 and 200 ms in the single-leg isometric squat and jump height (Pearson's correlation coefficient [r] = 0.45-0.48). Propulsive duration and relative propulsive mean force showed negligible to weak correlations with isometric variables, suggesting that the 2 tests assess distinct aspects of performance. These findings highlight that while the single-leg isometric squat can be used to reliably measure lower-limb strength, its predictive value for dynamic jumping ability is limited because of the weak-to-moderate associations with countermovement jump metrics. However, the test adds value by offering a low-fatigue, safe, and practical method for quantifying unilateral strength capacities over time. This contributes to more informed strength monitoring and individualized program design in artistic roller skating, where unilateral strength is important to performance.

Abstract: Wright, WC, Fedewa, MV, Aguiar, EJ, Winchester, LJ, Schumacker, RE, and Esco, MR. Accuracy of three field-based devices for measuring counter movement jump performance in elite female volleyball players. J Strength Cond Res 40(1): 112-117, 2026-The purpose of this study was to determine the accuracy of 3 field-based methods for assessing countermovement jump (CMJ) performance in elite female volleyball players, using force plate (FP) data as the criterion standard. Sixteen collegiate female volleyball players (age = 19.4 ± 1.5 years, height = 176.2 ± 10.6 cm, body mass = 71.5 ± 11.1 kg) performed the CMJ while being simultaneously measured by a jump-and-reach device (JR), linear position transducer (LPT), mobile phone application (APP), and a criterion FP system. CMJ height from the FP (36.16 ± 3.88 cm) was significantly lower than the JR (39.53 ± 5.18 cm, p < 0.01) and LPT (48.23 ± 4.44 cm, p < 0.01) but slightly higher than the APP (35.32 ± 3.75 cm, p < 0.01). In addition, the APP displayed the strongest correlation ( r = 0.99, p < 0.01) and smallest standard error of estimate (SEE ±0.27 cm) and 95% limits of agreement (±0.57 cm) compared with the other 2 devices. For CMJ, the mean power from the FP (2,243.00 ± 458.03 W) was significantly different from JR (2,615.69 ± 798.03 W, p = 0.02) and APP (1,354.31 ± 241.98 W, p < 0.01), but not the LPT (2,447.08 ± 559.32 W, p = 0.40). Although the correlations for mean power ( r = 0.61-0.76) between the field devices and criterion were significant ( p < 0.05), the SEE's (range ±310.90 to ±377.09 W) and limits of agreement (range ±655.28 to ±1,064.08 W) were considerably large. Based on the results, the APP seems to provide the most valid CMJ height measures. However, the caution should be used for assessing CMJ mean power with the field tools.

Abstract: Meira, Â, Ferreira Tramontin, A, Ribeiro, G, Santos de Oliveira Cruz, R, Alves de Aguiar, R, Klitzke Borszcz, F, and Caputo, F. Neuromuscular performance impairment: Exploring the power-force-velocity recovery profiles in local and nonlocal muscles. J Strength Cond Res 40(1): e9-e16, 2026-This study examined the effects of neuromuscular impairment on the time course of changes in the force-velocity-power profile in local (i.e., lower limb, assessed through back squat [SQ]) and nonlocal (i.e., upper limb, assessed through bench press [BP]) muscle groups following a repetitive lengthening protocol (RLP). Sixteen physically active men (age: 23 ± 3 years; 1 maximum repetition SQ relative to body mass: 1.5 ± 0.4 kg·kg -1 ) performed an RLP involving 5 sets of maximal 25 drop jumps designed to induce neuromuscular disruption. Back squat and BP exercises were used to assess neuromuscular performance changes in local and nonlocal muscles, respectively, by means of maximal theoretical force (F 0 ), velocity (V 0 ), and power output (Pmax) at baseline and at 24, 48, and 72 hours post-RLP. Delayed onset muscle soreness was measured at 0, 24, 48, and 72 hours. Significant reductions in F 0 and Pmax were observed in both exercises, with greater impairments in the SQ ( p ≤ 0.0001). V 0 was reduced in the SQ and remained unchanged in the BP, SQ change differed significantly from BP ( p = 0.008). F 0 remained suppressed across all time points ( p < 0.001), Pmax exhibited progressive reductions, peaking at 72 hours ( p = 0.001). Delayed onset muscle soreness peaked at 48 hours and resolved by 72 hours. These findings demonstrate that RLP impairs neuromuscular performance beyond the directly affected muscles, with persistent force deficits and task-specific reductions in velocity and power. This underscores the importance of monitoring both local and nonlocal muscles recovery kinetics when designing training and rehabilitation protocols.

Abstract: Bartkowiak, S, Kozieł, S, Krzykała, M, Karpowicz, K, Konarski, JM, and Malak, B. Are sex differences in youth weightlifting performance explained by fat-free mass? A controlled analysis. J Strength Cond Res 40(1): 68-75, 2026-This study examined sex differences in weightlifting performance among youth athletes, emphasizing the role of fat-free mass (FFM), strength, and power. Fifty-three competitive weightlifters (28 male, 25 female) aged 13-15 years were evaluated using bioelectrical impedance analyses to estimate FFM, along with assessments of hand grip strength, squat jump (SJ) power, and isometric mid-thigh pull force. Competition outcomes for the snatch, clean & jerk (C&J), and total weight lifted were recorded. Male weightlifters demonstrated significantly higher absolute strength outputs compared with female weightlifters ( p < 0.001). Regression analyses identified SJ power normalized to FFM as the strongest predictor of performance in male weightlifters across the snatch ( r2 = 0.3742, p < 0.001), C&J ( r2 = 0.3742, p < 0.001), and total ( r2 = 0.3945, p < 0.001). In addition, results from the forward stepwise linear regression indicated that waist-to-hip ratio emerged as a significant, sex-specific predictor of C&J performance ( p > 0.05). These findings underscore the importance of FFM and lower-body explosive strength in youth weightlifting success. However, inherent neuromuscular and biomechanical differences between sexes contribute to persistent performance gaps. The results support the implementation of sex-specific training strategies that target these unique physiologic profiles to optimize performance outcomes in youth weightlifters.

Abstract: Coffey, K, Pezzullo, L, Nixon, RM, Bolling, J, and Vincent, HK. A 10-year analysis of resistance training-related injuries treated in emergency departments: Are patterns shifting with more participation of women over time? J Strength Cond Res 40(1): e1-e8, 2026-This study reports current sex-related injury patterns associated with resistance training-related data from the National Electronic Injury Surveillance System (NEISS). This retrospective study includes patients seeking care for "resistance training" activity as defined by NEISS, encompassing the use of weight machines, barbells, dumbbells, and kettlebells. The prevalence, type and anatomical site of injuries, and hospital outcome were compared by sex. In total, 15,348 cases were included (20.40% female; 22.8 ± 6.3 years). Females sought care more frequently than males for accidental injuries including fracture (odds ratio [OR] = 1.27 [1.11-1.46]), contusion/laceration (OR = 1.52 [1.37-1.69]) and concussion/internal injuries (OR = 2.45 [2.02-2.97]). Males had 20 and 35% greater odds for reporting to the emergency department (ED) for exertional sprains/strains and dislocations, respectively (both p <0.05). Sites more frequently treated in the ED for females were the head, leg, and ankle/foot (all p < 0.050). The trunk was the most commonly injured site for both males and females (40.5 and 31.1%, respectively). Males had more crush injuries (3.10 vs. 2.20%, respectively) and injuries related to pressing movement (7.20 vs. 3.30%, respectively; p < 0.050). Females had more injuries related to dropped equipment (18.50 vs. 12.10%, respectively), falls (8.30 vs. 5.60%, respectively), and being hit by equipment (6.1 vs. 4.10%, respectively) than males ( p < 0.050). Gym environments were the most common injury sites for both sexes. Compared with earlier NEISS data, persistent sex differences exist with injury presentation in the ED, with an increase in concussions/internal injuries in females. Appropriate training regarding set-up and lift execution is critical to minimize these injuries. Prospective tracking that links specific type of lifting activity with specific injuries may provide a better understanding of how to reduce or prevent injuries.

Abstract: Lockie, RG, Beitzel, MM, Alvarez, DA, Sanchez, KJ, Orr, RM, Dawes, JJ, and Dulla, JM. Relationships between physical activity, general health and fitness, and job-specific fitness in law enforcement officers. J Strength Cond Res 40(1): e85-e94, 2026-Sedentary behaviors contribute to police officer fitness declines during their career, which may affect job performance. Physical activity (PA) could benefit general and job-specific fitness. This study derived relationships between PA and general and job-specific fitness in 60 officers (48 men, 12 women) from 1 law enforcement agency. Officers completed a questionnaire assessing PA (weekly strenuous, moderate, mild exercise sessions; activity score) and resistance training (RT) (resistance training frequency [RTF]; weekly sessions for 3 months [RT3M]; sessions in past 7 days [RT7D]). General fitness measures included resting heart rate (RHR), blood pressure, body composition, waist-to-hip ratio (WHR), sit-and-reach, grip strength, push-ups, sit-ups, and the YMCA step test. Job-specific fitness tests included an obstacle course, body drag, climbing tasks, and 500-yard run. Partial correlations controlling for sex calculated relationships between PA and RT with general and job-specific fitness. The sample was quartile split using activity score and examined by univariate analyses. Strenuous PA sessions related to RHR, WHR, push-ups, and sit-ups; activity score related to RHR and sit-ups ( r = ±0.27-0.36). Resistance training frequency related to RHR, WHR, push-ups, and sit-ups; RT3M related to RHR, push-ups, and sit-ups; RT7D related to push-ups and sit-ups ( r = ±0.31-0.43). The top quartile had a lower RHR than the bottom quartile and greater sit-ups than the bottom 2 quartiles ( p ≤ 0.03). There were no significant results for PA and job-specific fitness. Strenuous PA related to lower RHR and WHR, and better muscular endurance. Resistance training frequency related to lower RHR and better muscular endurance. General PA may not be sufficient for training job-specific fitness.

Abstract: Haghighi, AH, Shandiz, HH, Kakhak, SAH, Shahrabadi, H, Coswig, V, and Gentil, P. Plyometric and ballistic training have similar effects on young amateur male wrestlers' athletic performance. J Strength Cond Res 40(1): 98-105, 2026-This was a quasi-experimental study with a pretest and post-test design aimed at investigating the effects of resistance-plyometric training (RPT) compared with resistance-ballistic training (RBT) on the athletic performance of young amateur male wrestlers. Twenty wrestlers aged 16-18 years were randomly divided into RPT and RBT groups. The experimental groups participated in 3 sessions per week of the RPT or RBT program for 6 weeks in addition to their wrestling training routine during the preseason period. Before and after the intervention, the subjects were assessed for bench press strength, leg press strength, bench press endurance, leg press endurance, t test agility, 3-kg medicine ball throwing performance, Sargent jump performance, and specific wrestling tasks (flying mare, duck under, and rear throw). The results showed that both the RPT and RBT programs improved physical fitness (except for medicine ball throwing, which did not improve in RBT) and specific task performance (flying mare, duck under, and rear throw) with p < 0.05. There were no differences between the RPT and RBT programs in any of the physical fitness indicators or specific task performances ( p > 0.05). Considering that no significant difference was observed between the 2 types of training, young amateur male wrestlers could benefit from both RPT and RBT programs to improve their physical fitness and performance on specific tasks.