International Journal of Strength and Conditioning
International Journal of Strength and Conditioning (IJSC) The International Journal of Strength and Conditioning (IJSC), presented by the International Universities Strength and Conditioning Association (IUSCA), is a leading peer-reviewed academic journal dedicated to advancing research in sports science, sports performance, and strength & conditioning. As a Diamond Open Access journal, the IJSC ensures that all published research is freely accessible to the global community, fostering collaboration and innovation. Our mission is to provide high-quality, impactful research that bridges the gap between academia and practice. This mission is made possible through the generous support of organizations, institutions, and individuals who share our commitment to advancing the fields of sports performance and exercise science. Key partnerships with organizations such as JISC and LYRASIS enable us to maintain our open access model and ensure the sustainability of the journal. As a non-profit organization, the IUSCA relies on community and partner support to continue delivering free, world-class research to the strength and conditioning community. If you find value in the IJSC, please consider: Joining the JISC or LYRASIS schemes, or Making a tax-deductible donation to support our mission and the open access movement. ISSN: 2634-2235 International Universities Strength and Conditioning Association (IUSCA)
International Universities Strength and Conditioning Association (IUSCA)
Authors retain copyright of their work, granting IJSC a license to publish and distribute. All articles are distributed under the Creative Commons Attribution 4.0 License. We clearly state any fees associated with submissions or access for readers. For copyright or licensing queries, stakeholders can reach out to journal@iusca.org.
The Influence of Pre-Training Muscle Size on Strength Gain: An Exploratory Analysis
Purpose: To investigate whether changes in maximal strength following resistance training were influenced by pre-training muscle thickness. Methods: We retrospectively analyzed data from a between-subject study that measured elbow flexor muscle thickness and maximum strength before and after a 6-week study. A total of 122 untrained individuals, who were randomly assigned to 1 of 3 groups, were included in the analyses: (a) time-matched, non-exercise control; (b) dominant arm training; or (c) nondominant arm training. The two training groups performed thrice weekly unilateral elbow flexion exercise, starting with up to 5 heavy singles, followed by 4 sets of 8–12 repetitions to task failure. Results: Increases in strength were observed for both dominant arm [b = 2.29 kg, 95% CI = (1.72, 2.87)] and the non-dominant [b = 2.86 kg, 95% CI = (2.33, 3.39) training groups compared to the time-matched non-exercise control group. However, this increase in strength did not depend upon baseline muscle size for either group. Follow-up mediation analyses suggested that muscle growth mediated changes in strength for the dominant arm but not the nondominant arm training group. Conclusion: We hypothesized that individuals with larger muscles at baseline would have a greater propensity to increase strength compared to those with smaller muscles. However, the magnitude of strength change was not influenced by pre-training muscle thickness. Follow-up mediation analysis on muscle growth was equivocal.
Copyright (c) 2026 William Hammert, Jun Seob Song, Yujiro Yamada, Ryo Kataoka, Anna Kang, Robert Sallberg, Emily Metcalf, Jeremy Loenneke https://creativecommons.org/licenses/by/4.0
Predicting Maximal Aerobic Speed Through Set Distance Time-Trials in Camogie Players: A Pilot Study
Set distance time-trials (TTs) have gained popularity in research and practice as a reliable method for predicting maximal aerobic speed (MAS) in field sport athletes. Therefore, the aim of this pilot study was to investigate applicable TT distances for the establishment of MAS in camogie players. Senior club camogie players (n = 23) undertook the Yo-Yo intermittent recovery test (Yo-Yo IR1) to establish MAS, followed by participation in set distance TTs. In a randomised order, players from six balanced groups completed three different TT distances. The TT distances were 1.2 km, 1.4 km, 1.6 km, 1.8 km, 2.0 km, and 2.2 km. Bias, limits of agreement (LOA), linear regression, and bivariate correlation analysis determined the agreement between MAS and average running speed across the TT distances. The 1.2 km TT distance exhibited the least bias and narrowest LOA (-3.47 ± 0.43 km·h-1 [-22.16%] and ±1.68 km·h-1 [±10.73%], respectively). A strong (r = 0.80 [0.44 – 0.94], P = 0.001) to very strong (r = 0.98 [0.91 – 1.00], P < 0.001) positive correlation was found between MAS and average TT running speeds across all TT distances. MAS appeared to be best approximated by the 1.2 km TT in senior club camogie players.
Yo-Yo Intermittent Recovery Test – Level 1
Exercise Science/Exercise Physiology - Strength and Conditioning/Human Performance
Copyright (c) 2026 Seamus Ellis, Colin J. Coyle, Paul J. Byrne https://creativecommons.org/licenses/by/4.0
A Preliminary Investigation of the Relationship of Three Key Bar Positions on Weightlifting Performance
Background: There are three fundamental bar positions in weightlifting: 1) Set-up (S), 2) Knee (K), and 3) Power Position (P). Commonly, these positions are evaluated using a clean-grip isometric pull. Purpose: To compare and describe relationships between the three bar positions in an isometric pull and with meet performance in regional to international level weightlifters. Methods: Male (n=6) and female (n=6) weightlifters (age 19-23 yrs.) volunteered. Males were better weightlifters than the females. Pulls were performed from top-down (P - K - S). Isometric peak force (IPF) and rate of force development 0-250ms (RFD250) were derived from force-time curve analysis. A 2x3 mixed ANOVA was used to assess the effects of sex and position. Pearson correlations established relationships. Results: Males produced greater values (both absolute and relative) than females at all positions (p ≤ 0.05). IPF, IPFa and RFD250 at P were greater (p ≤ 0.05) than the other two positions. IPF and IPFa from S and K were similar. Correlations with performance were moderate to strong for absolute and scaled conditions; correlations were generally weaker for females. Correlations for IPF were stronger at S than P. RFD250 correlations were generally stronger at P. Conclusion: Metrics from S and P correlate better with performance than K, with IPF and IPFa favoring S while RFD250 favors P. Both positions seem to be viable options for monitoring weightlifters. Results indicate males and females may produce different relationships, perhaps indicating weakness at specific positions.
Copyright (c) 2026 Wesley Gawel, Marten Bauer, Chieh-Hsin You, Kyle Rochua, Daniel Gahreman, Guy Hornsby, Satoshi Mizuguchi, Michael Stone https://creativecommons.org/licenses/by/4.0
G-Force Tolerance in Fighter Pilots: A Scoping Review With Evidence Gap Map
Background: Despite growing interest in G-force tolerance, the literature remains fragmented, lacking an integrated synthesis that encompasses physiological, cognitive, training, and equipment-related dimensions. Fighter pilots are frequently exposed to high +Gz environments, which can compromise vision, cardiovascular stability, and consciousness. Understanding G-tolerance is vital for flight safety, operational readiness, and the long-term health of aircrew. Objective: This scoping review aims to map the existing evidence on G-force tolerance in fighter pilots and identify key physiological, anthropometric, cognitive, and operational factors. It also seeks to explore enhancement strategies and assess underrepresented populations, with the goal of guiding future research and improving pilot safety and performance. Methods: The review followed the JBI methodology and adhered to the PRISMA-ScR guidelines. Searches were conducted across eight databases and grey literature, including studies published up to March 31, 2025. A total of 118 studies met the inclusion criteria, encompassing a range of study designs and international contexts. Results: Findings revealed eight key themes: assessment and prediction of G-tolerance, physical conditioning, physiological and anthropometric factors, training and prevention strategies, equipment and technology, physiological effects of high-G exposure, risks and impacts, and external influences. Although AGSM proficiency, cardiovascular reflexes, and muscular strength were consistently associated with improved tolerance, substantial gaps were found in gender representation, longitudinal tracking, and integration of real-time physiological monitoring technologies. Conclusion: This review highlights the multifactorial nature of G-force tolerance and underscores the need for personalized, interdisciplinary approaches in pilot training and assessment. It provides a comprehensive foundation for future research aimed at optimizing high-G performance, with recommendations for standardized protocols, inclusive study populations, and expanded use of wearable monitoring tools.
Copyright (c) 2026 João Bruno, Hugo Sarmento, Raynier Montoro-Bombú https://creativecommons.org/licenses/by/4.0
Considerations and Recommendations for the Development or Enhancement of Undergraduate and Postgraduate Degrees in Strength and Conditioning
This paper consolidates existing literature into 10 research-informed considerations and recommendations for developing or enhancing undergraduate and postgraduate strength and conditioning (S&C) degrees in the United Kingdom. It is hoped these can inform discussions concerning the relevance, quality, and success of S&C degrees across stakeholder groups (professional associations, employers, degree representatives, and students/graduates) and support academic institutions and policymakers to further enhance S&C curricula.
Copyright (c) 2026 Anthony Weldon, Kevin Till, Jonathan Hughes, Ibrahim Akubat, James Keenan, Andrea Cameron, Anthony Turner https://creativecommons.org/licenses/by/4.0
Hitting the Brakes in Soccer: Individualised Thresholds for Assessing High-Intensity Decelerations during Matches
There is currently a lack of understanding surrounding how to quantify high-intensity deceleration actions in soccer. Therefore, this study sought to compare the use of arbitrary (ARB) and individualised (IND) high-intensity deceleration thresholds when examining the most demanding passages of play (MDP) and full matches. Fourteen male soccer players (age = 19.44 ± 1.13 yrs.; mass = 79.14 ± 7.88 kg; height = 184.16 ± 5.00 cm) were monitored during competitive matches using global positioning systems (WIMU Pro, RealTrack System SL, Almeria, Spain). IND thresholds were determined as 75% of a subject's peak deceleration ability from match data. ARB values were set as > 4m/s2 with the differences between these high-intensity deceleration thresholds analysed. ARB thresholds resulted in significantly (p < 0.01) larger distance and count metrics compared to IND during both MDP and full matches. These findings highlight the notable differences between ARB and IND high-intensity deceleration thresholds in matches. Thus, it is recommended a modified IND threshold approach is used when analysing the high-intensity deceleration demands of matches and MDP. Practitioners may be inclined to monitor high-intensity decelerations using IND thresholds, as is suggested when measuring other locomotor tasks during soccer training and matches.
Copyright (c) 2026 Liam Moore, Ben Drury, Andrew Hearn https://creativecommons.org/licenses/by/4.0
Exploring Strength and Conditioning Coaches’ and Stakeholders’ Perceived Value of A Workshop for Learning Psychosocial Coaching Competencies
Commonly used since at least the middle of the 20th century, action research can bridge the gap between science and practice, but within the field of strength and conditioning (S&C), it is a novel research approach. The education and development of S&C practitioners is essential to their understanding of evidence-informed practice and the application of knowledge to improve athletic performance, fitness, and other outcomes, including athlete-centered outcomes, such as well-being. Using a novel, multi-method action research approach, the purpose of this study was to understand S&C stakeholders’ perceived value of learning psychosocial S&C coaching knowledge. In collaboration with the United Kingdom S&C Association (UKSCA), we designed, delivered, and assessed a workshop that included modules on psychological, pedagogical, philosophical, and sociocultural S&C psychosocial coaching competencies. A total of 11 UKSCA participants, including 6 S&C coaches (5 men, 1 woman) and 5 stakeholders (3 men, 2 women), between 38-57 years of age, attended one of the two workshops. Multiple learner-centered activities were completed in the workshop, and then, participants completed data collection methods, including reflection grids and semi-structured interviews. Researchers performed a thematic analysis on the interviews, reflection grids, and field notes that resulted in two overarching themes: participants’ learning and instructional approaches used in the workshop. Participants perceived value from the content and instructional approach used in the workshop, while expressing challenges and recommendations for improvement. This original action research study advances the knowledge about S&C through a novel methodological approach and the education of S&C stakeholders’ psychosocial competencies.
Copyright (c) 2026 Dr. Brian T. Gearity, Dr. Bettina Callary, Mrs. Kimberley Eagles, Dr. Chris Szedlak https://creativecommons.org/licenses/by/4.0
A Framework Guide for the Selection of External Load Metrics in Ice Hockey
External workload monitoring has become commonplace in many sports, with staff looking to leverage the information gained to manipulate practice volume and intensity, hoping to maximize player readiness, minimize fatigue, and reduce the risk of injuries. However, with the increase in availability of technology to facilitate this, practitioners are faced with an overwhelming selection of metrics to choose from. Collinearity, contradiction and the accurate quantification of relative metrics risk creating confusion, and therefore it may benefit practitioners to have some guidance to help in the process of metric selection. This framework aims to provide clarity in the underpinning theory, history and development of external workload monitoring practice, a series of questions for reflective practitioners to consider, and evidence-based practical suggestions for its use.
Copyright (c) 2026 Steven Nightingale, Jonathan Hughes, Mark De Ste Croix, Craig Pfeifer https://creativecommons.org/licenses/by/4.0
Effects of Load on Lower Extremity Joint Kinetics and Kinematics during Hexagonal Barbell Jump Squats
Strength and conditioning coaches often recommend athletes perform loaded jumps with an external load that maximizes peak power output to improve performance. However, there is debate regarding the training load that maximizes acute total body power, and power at individual lower extremity joints. The purpose of this study was to investigate lower extremity kinetic and kinematic variables across a spectrum of loads during jump squats using a hexagonal barbell. Participants performed jumps with a range of loads from 10% to 60% of hexagonal barbell deadlift estimated 1-repetition maximum (e1RM), as well as an unloaded countermovement jump. Using cameras and force plates, lower extremity angles, velocities, moments, powers, as well as total body power, were assessed for each jump. As load increased, there was a decrease in power at the total body level and the hip, but ankle power increased. All joint moment magnitudes increased with load, and flexion angle and velocity at the hip and knee decreased with load. Results suggest that increasing load impacts kinetic and kinematic variables and alters the jumping task, and that the majority of these changes occur when loading exceeds approximately 20-30% 1RM. Further, knee kinetics measures were most strongly related to total body power.
Copyright (c) 2026 Jacob F. Remmert, Abigail K. Salvadore, Adam E. Jagodinsky, Marcel Lopes dos Santos, Michael R. Torry https://creativecommons.org/licenses/by/4.0
Stakeholders Perceptions of Undergraduate and Postgraduate Strength and Conditioning Education in the United Kingdom: A Survey Study
The number of strength and conditioning (S&C) degrees in the United Kingdom has grown alongside the discipline’s popularity. The design and development of these degrees are influenced by various stakeholders, including S&C association representatives, potential employers, degree representatives, students, and graduates. Prior to this study, the collective perceptions of these stakeholders regarding UK S&C degrees had not been researched. This study filled this gap by reporting on the results of 73 participants who completed a one-time anonymous survey, consisting of six sections: (a) background information, (b) degree endorsement, recognition, and accreditation, (c) course structure, (d) placements, (e) module topics, and (f) further information. Frequency analysis was employed for fixed-response questions and thematic analysis for open-ended questions. Participants valued S&C associations and their role in providing degree endorsements, recognitions, and accreditations as they demonstrate quality assurance and alignment with industry standards. However, they felt that professional qualifications from these associations should be more integrated into degree programmes. Regarding degree content and structure, participants agreed that undergraduate degrees should focus on foundational knowledge (e.g., physiology), while postgraduate degrees should cover specialised S&C content and applied practice (e.g., placements). However, some differences in opinion were observed concerning module topics, with participants lacking interest in research-based modules, despite being common, especially at postgraduate level. Placements were considered very important for gaining authentic practical experience, with most participants recommending they be compulsory. Although, flexibility was recommended for students with existing industry experience. These findings provide valuable and needed insights into current perceptions of UK S&C degrees, which may inform stakeholders decisions and practices, lead to closer alignment between stakeholder groups, and create beneficial changes for UK S&C degrees.
Effects of Optimum Power Load vs Mixed Model Training Methods on Lower Limb Strength and Dynamic Performance in Female Athletes
Training with optimum power load (OPL) was shown to result in improved lower limb strength. However, recent study has recommended using the mixed model training (MMT) method which involves frequent varying of training loads. As the training adaptations to OPL and MMT training methods have not been directly compared, hence, the purpose of this study was to compare the effects of OPL and MMT on lower limb neuromuscular adaptations. Seventeen female athletes (age: 22±2.9 years, height: 162.7±5.2 cm, bodyweight: 60.5±9.6 kg) were randomly assigned to either MMT or OPL training (OPLT) group. Both groups performed similar training program twice a week for six weeks. However, MMT performed the loaded CMJ exercise at -15-20% and +20-25% of OPL, while OPLT performed it at OPL. Pre- and post-test included CMJ, 5-0-5 change of direction test (505 COD), 20-m sprint and isometric mid-thigh pull (IMTP). Both groups showed significant improvement in CMJ height (MMT: P=0.025, g=0.48, OPLT: P=0.003, g=0.72), 505 COD (MMT: P<0.001, g=1.12, OPLT: P=0.006, g=0.36), 20-m sprint (MMT: P<0.001, g=0.65, OPLT: P=0.002, g=0.28), IMTP peak force (MMT: P<0.001, g=0.66, OPLT: P<0.001, g=0.46) and IMTP force at 100 ms (MMT: P=0.019, g=0.66, OPLT: P=0.001, g=0.60). Only MMT significantly improved CMJ mean propulsion force (P=0.004, g=0.34), a variable that contributes to greater jump height. While OPLT resulted in greater effect for CMJ height, MMT resulted in greater effect for 505 COD, 20-m sprint and IMTP performance. These findings suggest that frequent varying of resistance may induce greater neuromuscular adaptations.
Copyright (c) 2026 Terence Kwee Hao Chua, Pui Wah Kong, Danny Lum https://creativecommons.org/licenses/by/4.0
Coaching Insights into Pickup Acceleration
In team sports, sprint acceleration from a moving start, or, in coaching terminology, “pickup acceleration”—is a critical, yet different, skill that occurs more frequently than acceleration from a static start. Despite its importance, pickup acceleration remains underexplored compared to traditional sprint mechanics, which primarily focus on stationary starts. Given the paucity of research, a practice-based evidence approach was employed in this study, gathering insights from expert coaches (N = 13, coaching collegiate, professional, Olympic, or elite high school athletes) to identify the essential physical and technical attributes for enhancing pickup acceleration performance. The surveyed coaches identified lower body force and power production (54%), lower body elasticity and stiffness (38%), hip and ankle range of motion (15%), coordination (38%), and core rotational strength and stability (31%) as essential physical qualities for pickup acceleration proficiency. From a technical perspective, the change in center of mass height (31%) and center of mass angle (46%), anterior touchdown distance, and shin angle (23%), hip separation angle (23%), and optimization of step kinematics (step length and step frequency; 31%) were thought crucial to maximizing acceleration and efficiency. Additionally, distinctions were noted between acceleration from walking versus jogging starts, with each entry type requiring specific adjustments in force application and body alignment. Understanding the determinants and how to assess pickup acceleration can help delineate between track speed and sports speed, enabling coaches to tailor pickup acceleration training for improved performance in terms of sport specificity.
Copyright (c) 2026 Mark Pryer, Prof. John Cronin, Dr. Jono Neville, Chris Korfist, Dr. Aaron Uthoff https://creativecommons.org/licenses/by/4.0
The Relationship Between the Jiu Jitsu Anaerobic Performance Test and Physiological Markers in Trained Jiu Jitsu Practitioners
Jiu Jitsu relies on aerobic and anaerobic energy systems. A relationship has been demonstrated between the Jiu Jitsu Anaerobic Performance Test (JJAPT) and anaerobic performance. The relationship between the JJAPT and aerobic performance has yet to be quantitatively defined. The purpose of this study was to determine if there is a relationship between the JJAPT and maximum oxygen uptake and ventilatory threshold (VT). Twenty-five Jiu Jitsu subjects participated in two test sessions a minimum of 48 hours apart. During one test session, descriptive statistics were collected, a self-guided treadmill warm-up was completed, followed by the Bruce graded exercise protocol. Ventilatory threshold was determined by computer plotting VO2peak and ventilation onto a line chart and confirmed by two researchers. Ventilatory threshold percentage was calculated by hand. The second test session included a JJAPT familiarization warm up and the JJAPT. Pearson correlation was used to determine the relationship between the JJAPT and VO2peak and between the JJAPT and VT. The main findings revealed a significant moderate positive correlation between VO2peak and the JJAPT, (r = 0.40, p = 0.025). Research has shown that Jiu Jitsu has dispersed lower intensity aerobic periods with more reliance on the anaerobic system. The moderate correlation with VO2peak is consistent with the energy system requirements for Jiu Jitsu. This study, in combination with previous studies, indicates the JJAPT provides reliable measures of Jiu Jitsu competition performance. It’s been concluded that the JJAPT could be used to evaluate BJJ athletes and track performance improvements.
Aerobic relationship in Jiu Jitsu Anaerobic Performance Test
Copyright (c) 2026 Renee Peveler, Justin Kilian, Will Peveler https://creativecommons.org/licenses/by/4.0
The Reliability and Validity of Isometric Midthigh Pull Measures Obtained from a Portable Isometric Dynamometer
The purpose of this investigation was to establish the reliability and concurrent validity of measures of peak and early force production obtained from a portable isometric dynamometer (PID). Twenty resistance trained males completed one familiarization and two isometric mid-thigh pull testing sessions separated by 48-72 hrs. During testing sessions data was simultaneously collected from the PID and force plates (FP) both sampling at a frequency of 1000 Hz. Measurements of peak force (PF) and force at 100 ms (Force100) and 200 ms (Force200) obtained from both the PID and the FP demonstrated acceptable reliability (ICC’s = 0.793-0.966; CV% = 2.7-9.2%). However, PF was significantly and meaningfully greater (P < 0.001; d = 1.00) 1.27% greater when obtained from the FP compared to the PID. In contrast, Force100 obtained from FP was significantly lower to that obtained from PID by 229% (P < 0.001; d =3.96). Similarly, Force200 obtained from FP was significantly lower to that obtained from PID by 38.87% (P < 0.001; d = 1.43). Whilst the measures of force production obtained from the PID was shown to have acceptable reliability they displayed questionable validity, particularly with respect to measures of early force production.
Sport Science; Strength and Conditioning
Copyright (c) 2025 Danny Lum, Lachlan P. James, Luke Stutter, Scott Talpey https://creativecommons.org/licenses/by/4.0
Power! A Field Based Testing Resource for Strength & Conditioning Personnel
Power may be the most vital physical trait towards successful sport performance. Whether competing in team sports such as basketball and rugby; individual sports including track and field events, tennis, and golf; endurance based events encompassing cross country skiing, marathon running, and long distance swimming; or even tactical occupations, power development and maintenance is crucial to an athletes’ success. The specific power component most vital to success should be identified, monitored, and tested to ensure continued development and/or maintenance throughout a competition calendar. By conducting a needs analysis, the specific contributions of power to a given sport can be determined. Equally important as knowing how to develop power, is also knowing what economic field based tests are available to accurately assess athletic development. The purpose of this article is to provide strength and conditioning coaches (SCC) across numerous levels/populations and having various levels of funding, with a brief overview, categorization and coaching resource for the vast array of field testing methods available to assess and monitor whole, upper, and lower body power.
Copyright (c) 2025 Ian Bonder, Dr. Mike Waller, Marc Tangeman, Dr. Andrew Shim https://creativecommons.org/licenses/by/4.0
Flywheel Resistance Training for Anterior Cruciate Ligament Rehabilitation
The tearing or rupturing of the anterior cruciate ligament (ACL) has become an increasingly common injury in athletes, particularly in sports that require sharp, pivoting movements and sports that have high deceleration and landing demands. Optimizing each stage of rehabilitation post ACL reconstruction (ACLR) is crucial for successful recovery and the return-to-play of an athlete. Researchers have highlighted the importance of deceleration training and the role of increased eccentric force production and the ability to attenuate rapid braking forces prior to an athletes return-to-sport. There are many training methods that can provide this eccentric overload; however, the focus of this review is on the utility of flywheel resistance training (FRT) during ACL rehabilitation. An overview of the literature that has determined the effects of FRT on ACL rehabilitation post ACLR is discussed, including the current loading parameters, and limitations of the research. A new perspectives of late-stage ACL rehabilitation with FRT is then proposed, with practical examples provided.
Multidisciplinary Perspectives on Injury Prevention, Rehabilitation, and Performance in Sport
Copyright (c) 2026 Margaret Michalak, Dr. Chloe Mihi Ryan, Dr. Alex Ehlert, Dr. John Cronin https://creativecommons.org/licenses/by/4.0
A Retrospective Self-Reported Audit of Injuries Amongst Grappling Athletes Competing in the United Kingdom
Purpose: This study aimed to estimate the incidence, prevalence, type, and mechanism of injuries among grappling athletes in the United Kingdom (UK) across the following disciplines: Brazilian Jiu-Jitsu (BJJ), Judo, Catch Wrestling, Sambo, and Mixed Martial Arts (MMA). Methods: A retrospective, self-reported survey, delivered via JISC online survey software, was used to record the following information for all injuries sustained over the previous 12-month period: mechanism of injury, environment, severity, recurrence and body region. Additionally, injury diagnosis was reported where possible. Injury incidence for training exposure was calculated based on hours trained per week, while competition exposure was based on the number of bouts participated in during the year. One variable chi-square tests (X2) were used to calculate if observed values were significantly different from expected values. Results: A total of 341 grappling athletes, 243 males and 97 females, with one participant preferring not to state gender (32 ± 9.3 years), completed the study over a 3-month period. The competition incident rates (IR) (24.16/1000 AE) were significantly higher than training (2.97/1000 AE). The knee was the most frequently injured site (24.5%). Ligament sprains were the most commonly diagnosed injury (24.3%). Most injuries occurred during practice sparring (65.8%), with the leading mechanisms being submission attempts and takedowns. Major injuries (>28 days recovery) accounted for 49.5% of all cases. BJJ exhibited the highest injury rate (3.49/1000 AE); patterns varied by discipline and gender. Conclusion: Grappling sports pose a substantial risk of injury, particularly to the knee. Structured training, medical support, and tailored injury risk reduction programs should now be explored to enhance athlete safety.
Copyright (c) 2026 Jonathan Bell, Eleanor Travis, Ashley Jones https://creativecommons.org/licenses/by/4.0
Development of an Independent Regulatory Council for the International Qualification Framework: International Universities Strength and Conditioning Association Position Statement
The establishment of the International Qualification Framework (IQF) represented a seminal advancement towards standardising education and certification levels in the profession of strength and conditioning (S&C). By providing a standardised and internationally unified structure, the IQF directly addresses the long-standing disparities and inconsistencies noted in education and qualification recognition globally. However, the credibility and effectiveness of such a global qualification framework depends upon robust policies and detailed independent regulatory oversight. The IQF Independent Regulatory Council (IQF-IRC) has therefore been established as an autonomous body, specifically designed to oversee the IQF including its education, accreditation, and certification processes. This position statement outlines the governance structure, core responsibilities, professional relevance, and strategic objectives of the IQF-IRC. It will also discuss the benefits of voluntary alignment by global S&C organisations, ultimately fostering a cohesive and universally accepted education and accreditation system that can be presented to the wider industry and public.
Copyright (c) 2025 Andrew Langford, Aden Flannagan, Stephen P. Bird, Paulo Marchetti, Timothy J. Piper, David Morley https://creativecommons.org/licenses/by/4.0
Position-Specific Benchmarks for Jump and Reach Metrics in the National Basketball Association Draft Combine
This study analysed data from the NBA draft combine and aimed to establish position-specific normative data for jump and reach performance to support coaches in better assessing the jumping ability of basketball players. Data on body height with shoes, standing reach (STReach), vertical jump reach (VJReach), and running jump reach (RJReach) were obtained from publicly available sources for 1,048 players who participated in the NBA draft combine between the 2004-05 and 2022-23 seasons. Vertical jump height (VJHeight), running jump height (RJHeight), and run-up effect (RE) were calculated. These variables were then compared across five playing positions; point guard, shooting guard, small forward, power forward, and center and position-specific percentile scores were generated to create normative data. Results showed that RJReach significantly increased from guards to centers (p < .05), primarily reflecting positional differences in anthropometry. Notably, guards demonstrated significantly higher VJHeight, RJHeight, and RE (p < .05) compared to power forwards and centers, indicating that shorter players may compensate for their height through enhanced vertical jump and RE. Furthermore, height and STReach progressively increased from guards to centers, highlighting the contribution of anthropometric, non-trainable characteristics. VJReach and RJReach increased across positions, and this increase was significant between all positions but power forwards and centers. RE was higher in guards and forwards than in centers. These results imply that RE may capture unique, trainable aspects of jump performance. This study presents position-specific benchmarks for jumping ability, offering strength and conditioning coaches practical reference values to assess players’ strengths and weaknesses and to design tailored training programs.
Copyright (c) 2026 Hiroki Ogata, Henderson Frederick, Daichi Yamashita https://creativecommons.org/licenses/by/4.0
Concurrent Validity and Reliability of the My Jump Lab Smartphone Application for Break Point Angle Assessment in the Nordic Hamstring Exercise
The Nordic Hamstring Exercise is widely used to prevent muscle strain injuries. Although isokinetic dynamometry is considered a gold standard for assessment, it is often impractical in many settings, due to several reasons. A cost-effective alternative for physical evaluations of the same muscle could be Smartphone-based, which have greatly increased in recent years due to technological advancements. This study aims to assess the concurrent validity and inter-rater reliability of the My Jump Lab smartphone application in measuring the break point angle (BPA) during the Nordic Hamstring Exercise. Twenty-four healthy participants were recruited for this study and performed five repetitions of the nordic hamstring exercise, while being recorded via smartphone for BPA estimation. The same exercise was compared with kinematic analysis, as reference method. Concurrent validity was assessed by Pearson’s product-moment correlation coefficient and Bland-Altman Plots, while inter-rater reliability was analysed by intraclass correlation coefficient (ICC), coefficient of variation (CV) and standard error of measurement (SEM). Results revealed a very high and significant level of correlation (r > 0.9, p< 0.001) for break point angle measurements, with small proportional bias. The app showed excellent inter-rater reliability (ICC >0.9), with very small variations (CV ≈ 1%) and SEM lower that 1.3 degrees. These outcomes suggest that My Jump Lab is a valid and reliable tool for BPA assessment, that can be used confidently to assess hamstring muscle strain in a simple, portable and practical manner.
Copyright (c) 2025 Amandio Dias, André Gomes, Diogo Nogueira, Leonel Correia, Rodrigo Trindade https://creativecommons.org/licenses/by/4.0
A Comparative Biomechanical Analysis of the Farmers and Zercher Carry Exercises
ABSTRACT The loaded carry is a movement pattern characterized by walking for a set time or distance with an externally applied resistance. The application of an external load alters the body’s biomechanics, creating an environment for potential adaptation and performance enhancement. Further, the location of the load may have additional adaptation implications as a result of center of mass (CoM) changes which may impact body stability. Specifically, a resistance carried anterior to the body as done in the Zercher Carry (ZC), causing a vertical and anterior translation of the CoM, may stimulate different compensatory mechanisms from the Farmers Carry where the load is held at the sides of the body, keeping the CoM in its relative anatomical location. To investigate this, healthy, college aged individuals were recruited and their anthropometric data was captured. Participants were then prepped for surface electromyography with electrodes placed on their dominant side rectus abdominis, external oblique, multifidus, longissimus, upper trapezius, and middle deltoid. Maximal voluntary isometric contractions were performed to standardize muscle activation. Participants were outfitted with inertial measurement units for the trunk and lower limb to capture gait and joint kinematics. One counterbalanced 5-meter walk loaded with 100% fat free mass was completed for each exercise with participants stepping on a force plate halfway to capture single step ground reaction forces (GRF). Data for all variables were compared utilizing a MANOVA. Comparisons between the FC and ZC revealed significant differences (P < 0.05) in muscle activation (e.g., multifidus: FC 12.0 ± 6.7 v. ZC 25.4 ± 13.0), joint kinematics (e.g., lumbar extension: FC -4.4 ± 4.1 v. ZC 2.0 ± 6.5), gait (e.g., stride length: FC 108.1 ± 9.4 v. ZC 101.4 ± 9.4) and GRFs (e.g., anterior GRF: FC 22.3 ± 6.8 v. ZC 17.5 ± 7.4). The differences observed between the ZC and FC as a result of load position may implicate unique adaptation and influence how these exercises should be implemented in resistance training programs.
Copyright (c) 2026 Accalia D. Decker, Justin M. Fagley, Shaylyn A. McNally, Zachary M. Regalski, Kaylee C. Rhinehart, Ava V. Urda, Michael E. Holmstrup, Jeremy R. Dicus https://creativecommons.org/licenses/by/4.0
Measuring Impulse-DSI and its Derivatives Via the Isometric Belt Squat: Assessing Relationships with Sprint Ability Among Division 1 Team Sport Athletes
The dynamic strength index (DSI) is a common athlete profiling tool that has traditionally been derived as the ratio between the peak force in the isometric mid-thigh pull (IMTP) and the countermovement jump (CMJ) to identify ballistic strength deficits. Recently, an impulse-based DSI (iDSI) has been proposed for the relevance of impulse metrics in explosive sports. Furthermore, the isometric belt squat (IBSq) may be a superior alternative to the IMTP for measuring lower-body force potential owing to its removal of the torso and upper limb involvement. This study assessed the reliability of two novel IBSq and CMJ 200ms impulse metrics. Furthermore, we assessed the individual relationships and predictive utility of the DSI derivatives and 40m sprint performance. 43 Division 1 team sport athletes (30 males and 13 females) were recruited. Reliability was assessed using the intraclass correlation coefficient (ICC) and the coefficient of variation (COV). The relationships between DSI and iDSI derivatives, 0-10m, 10-30m, and 30-40m split times were assessed using Pearson’s correlation coefficient and stepwise regression. The IBSq and CMJ impulses demonstrated acceptable reliability (ICC > .93, COV < 9.6%). IBSq and CMJ impulses explained up to 56% of the variance in 0-10m time (p <.002) and up to 49% of the variance in 30-40m time (p <.0001). The IBSq-derived iDSI score may be a reliable and accurate test for predicting sprint performance among Division 1 team sport athletes. Practitioners may monitor iDSI derivatives to enhance training decisions relevant to sprint speed.
Copyright (c) 2026 Matthew Ward https://creativecommons.org/licenses/by/4.0
Physical Profile of Strongman and Strongwoman Athletes
While strongmen and strongwomen are among the strongest athletes in all sports, limited literature is available pertaining to the physical and physiological characteristics of this population, including their vertical jump ability. Thus, the purpose of this study was to profile a cohort of strongman and strongwoman competitors at an international strongman/strongwoman event and measure jump performance differences between competitors (currently active strongmen/strongwomen) and resistance-trained individuals (individuals not strongmen or strongwomen at the event). Twenty-three subjects who attended an international strongman and strongwoman event (age:27.7±5.9 years; weight: 116.3±30.4 kg) volunteered to participate in the present study. Weight, hand length, hand grip strength, self-reported one repetition maximum for common powerlifting exercises, and specific countermovement vertical jump (CMJ) and squat jump (SJ) metrics were analyzed for between-sex differences within the sport. The present study's findings reveal that hand length, hand grip strength, and self-reported one repetition maximum for common powerlifting exercises were significantly higher for strongman competitors. For CMJ and SJ, both relative and absolute mean and peak velocity, force, and power in eccentric and concentric phases were significantly higher for strongman competitors. Contraction times were shorter for strongmen in both CMJ and SJ than strongwomen but were non-significant. Interestingly, the eccentric utilization ratio and the stretch-shortening cycle percentage did not significantly differ between strongman and strongwoman competitors, however, the entire cohort's eccentric EUR was considerably less than 1.2, indicating higher overall strength than ballistic power. The present study was able to profile the physical and jump performance characteristics of strongman and strongwoman competitors.
Copyright (c) 2026 Yang Yang, Quincy Johnson, Nicolas Philipp, Drake Eserhaut, Joe Kenn, Dimitrije Cabarkapa, Andrew Fry https://creativecommons.org/licenses/by/4.0
Profiling the Physical Conditioning Attributes of Young Male Gaelic Football Players: From Adolescence to Adulthood
This study assessed the anthropometry and physical conditioning attributes of young male inter-county (national level) Gaelic football players, comparing possible differences according to age categories (under-14 [U14] to under-21 [U21]) and position. In total, 3547 assessments were undertaken in 2588 players across a 10-year period (2013 to 2023). Assessments included anthropometry (stature, body mass, sum of 3 skinfolds), flexibility (sit and reach test), muscular power (countermovement jump and standing long jump), running speed (5-m and 20-m), muscular endurance (maximum push ups) and aerobic capacity (yo-yo intermittent recovery test level 1 [YYIRT1]). Increases were demonstrated when comparing age categories from U14 to U21 for anthropometry (e.g., height [cm] +5.7%), muscular power (e.g., Standing long jump [cm] +16.1%). running speed (e.g., 5 m speed [s] -4.8% from U14 to U20), running momentum (e.g., 20 m momentum [kg.ms-1] +41.5% from U14 to U20), muscular endurance (push-ups [n] +107.7%), flexibility (sit and reach [cm] +36.0%) and aerobic capacity (YYIRT1 [m] +42.3%). When comparing positions, goalkeepers and midfielders were taller and heavier than backs and forwards, respectively. Additionally, midfielders displayed superior aerobic conditioning when compared with other positions, while goalkeepers displayed significantly lower aerobic conditioning. These findings offer comparative data of young Gaelic football players from varying age categories (U14 to U21) which are further classified according to positions. Practitioners may utilize this data to inform player identification processes, characterize position-specific benchmarks and monitor physiological adaptations in young players.
Copyright (c) 2025 Lorcan Daly, Cathal Cregg, Daniel Forde, Ciarán Catháin, David Kelly https://creativecommons.org/licenses/by/4.0
Strength, Power and Anaerobic Capacities of Male Judo Athletes across Age and Competitive Levels
Purpose: This cross-sectional study evaluated the physiological profiles of judo athletes across age and competitive levels, aiming to identify key physiological determinants of judo success. Methods: Thirty-eight judokas from three age/competitive levels (cadet + junior, non-Olympic senior, and Olympic senior), spanning various weight classes and ages, were assessed for strength, power, and anaerobic qualities. Performance tests included countermovement jump, drop jump, maximal grip strength, and upper body Wingate anaerobic test (WIN) and results were normalized to body mass. Strength values were obtained from the athletes’ self-reported training programs and normalized to competition weight class. Comparisons of the physical measures were made across age/competitive levels and a qualitative evaluation based on success in national vs. international competitions was made within the groups. Results: Significant differences in absolute values were observed between age/competitive level groups; however, most differences disappeared after normalization. The only persistent differences were in relative WIN peak power and relative WIN mean power, which were greater for the senior athletes compared with the cadet + junior group. No significant differences were found between quality levels within the groups. Conclusion: In the within-group analysis, it was not possible to differentiate high vs. low quality level male judo athletes in our cohort. When comparing the three groups, only relative WIN peak and relative mean power were significantly different between groups while other measures lost significance when normalized. This strengthens the notion that anaerobic power and capacity are relevant to judo success.
Copyright (c) 2025 Idan Harat, Dr. Rotem Kislev-Cohen, Dr. David H. Fukuda https://creativecommons.org/licenses/by/4.0
The Role of the Strength and Conditioning Coach in Return-from-Injury Care: A Survey Study
The purpose of this study was to describe the perceptions of strength and conditioning coaches (SCCs) regarding professional roles and decision-making related to return-from-injury care in the National Collegiate Athletic Association (NCAA) to identify areas of opportunity related to effective completion of the rehabilitation continuum. Sixty-seven SCCs completed a web-based survey. Means, standard deviations, and frequency of responses were used to report results. SCCs perceive their roles to be most significant in advanced training, training systems not specific to the injury, and late-stage strength/function. Only 72% of Head SCCs and 66% of Assistant SCCs perceive their role to include shared development of training sessions for return to performance, which is an aspect of their scope of practice; fewer are included in return to sport programming. Less than one third make any recommendations for clearance to progress to the next stage in rehabilitation. SCCs expressed a desire for a larger role in decision-making regarding readiness for full return to competition, yet only 68% of Head SCCs and 59% of Assistant SCCs report they conduct any testing for the final transition to return to performance. Areas of opportunity for the SCC include conducting assessments related to return to sport and full return to performance to contribute to progression/clearance recommendations and contributing to the end stage program design for effective completion of the rehabilitation continuum. These integral components of the rehabilitation continuum could allow the SCCs to have a more defined role and greater voice in return-from-injury care.
Copyright (c) 2026 Erin Choice, Rebecca Downey, Maren Clark, Gabrielle Haugh, Trevor Short https://creativecommons.org/licenses/by/4.0
Unlocking Basketball Athletic Performance: Countermovement Jump Rebound (CMJ-RE) Normative Reference Values Derived from Force Plate Data Across Seven NCAA Division-I Power Five Men’s College Basketball Teams
Purpose: This study examined the emerging countermovement rebound jump (CMJ-RE) test as an alternative to the drop jump (DJ) to grade reactive strength abilities in elite basketball players. Normative percentile data, rebound jump filter criteria, novel effort metrics, and reliability statistics were analyzed in order to better define the standards for a high-quality CMJ-RE test and to democratize the measurement of reactive jump testing. Methods: 96 NCAA Division-I men’s college basketball players from seven teams performed the CMJ-RE (bounce-method) on bilateral force plates with hands on hips during the 2023-2024 pre-season. Only 87 players met the quality filter criteria for further analysis (three centers, 31 forwards, 53 guards); the center position was not compared in depth due to the limited sample size. Results: Between forwards and guards, positional differences were found for 37% of the 38 reported jump metrics, with guards showing higher rebound jump heights (JH), all other metrics (p < 0.05) favored forwards. Mean ground contact times (GCT) for both positions were >250 ms. On average for both positions, the first jump in the CMJ-RE was completed at 94% JH of a previously collected standalone CMJ JH; and the second jump was completed at 98% JH of the first CMJ-RE JH. Furthermore, percentile ranges (3rd to 97th) accompanied by qualitative descriptors and a traffic light classification system were reported. Conclusion: Overall, the CMJ-RE (bounce-method) is a reliable alternative to the DJ for assessing reactive strength qualities in elite basketball players and may be more sport-specific, due to players frequently performing subsequent jumps rather than one single effort jump. The normative data prepared in this study should serve as a reference point throughout the evaluation of reactive strength for basketball performance coaches and in the return to play process for sports medicine professionals. Those administering the CMJ-RE should use the filter criteria measures outlined in this paper to ensure quality and effort are being met.
Copyright (c) 2025 Drake Berberet, Adam Petway, Karah Bell, Zach Gillen, Peter Mundy, Henry Barrera, Jason Kabo, Dom Walker, Garrett Medenwald, Braden Welsh, John McMahon https://creativecommons.org/licenses/by/4.0
Effects of High and Low Intensity Endurance Training With and Without Blood Flow Restriction on 3-km Running Performance
We investigated the effects of high- and low-intensity endurance training, with and without blood flow restriction (BFR), on 3-km running performance in recreational athletes. Thirty-one recreationally trained runners (18 men and 13 women, age: 39 ± 5.2 years, height: 171 ± 7 cm, body mass: 71 ± 11 kg) were divided into 4 groups: low-intensity group (LI) and low-intensity group with BFR (LI+BFR) who completed 3 km at 60% vVO2peak; high-intensity group (HI) and high-intensity group + BFR (HI+BFR) who completed 10 × 300 m at 90% vVO2peak with 90 s of recovery. Participants performed the experimental protocols twice a week for 4 weeks in addition to their regular training. Before and after the 4-week intervention, participants completed a 3-km and an incremental test on the treadmill. LI + BFR, HI, and HI + BFR improved 3-km performance, while LI had not effect. Changes in LI + BFR and HI + BFR were greater than those observed in LI. BFR added to endurance training may help improving performance in recreationally trained runners with specific adaptations depending on the intensity used.
Copyright (c) 2026 Rafael Augusto Aragon Rodrigues, Everton Crivoi do Carmo, Daniel Boullosa, Charles Ricardo Lopes, Márcio Antônio Gonsalves Sindorf, Renato barroso https://creativecommons.org/licenses/by/4.0
A Retrospective Analysis of Powerlifting Performances in the U.S. (1995 - 2005)
In this retrospective study, powerlifting performances in the United States from 1995 – 2005 were taken from annual top 100 rankings published in Powerlifting USA magazine. The rankings included results for the squat, bench press, deadlift, and total for each standard weight class during a calendar year. In the current study, average performances for each weight class were compiled for the #1, #10, #50, and #100 ranks. The weights lifted for each category increased as a function of the competitor’s weight class in a curvilinear pattern, with the heaviest classes showing diminishing improvement in weight lifted with increased body weight. When weights lifted were standardized to the lifter’s weight class, a unimodal curve was observed, with maximal values being in the middle weight classes. The lower mass-specific performance in heavier lifters is the basis for Wilks coefficient and other adjustments for comparing performances among different weight classes. This coefficient is a mathematical formula based on a polynomial transformation of a lifter’s weight class. It was derived to compensate for the curvilinear nature of lifting performance as a function of body weight. Based on the patterns documented, it is proposed that part of this flattening of performance can be attributed to systematic differences in body composition across weight classes. During this 11-year period, significant improvements were observed for some lifts, ranks, and weight classes. However, many did not change, while others showed significant declines. These data demonstrate that U.S. powerlifters at the turn of the century were highly competitive, particularly within the middle through the heaviest weight classes. Overall, the lifting performances in the U.S. during this decade provide an historical reference point, from a time before powerlifting records became more widely available via the internet.
Copyright (c) 2026 Scott Medler https://creativecommons.org/licenses/by/4.0
Comparison of Peak Force and Myoelectric Activity of the Anterior and Middle Deltoid at Three Shoulder Angles During Frontal, Diagonal, and Lateral Raise Exercises in Trained Men
The objective of the present study was to compare the peak force and myoelectric activity of the anterior (AD) and middle deltoid (MD) at three different shoulder joint angles during the frontal (FR), diagonal (DR), and lateral raise (LR) exercises in recreationally-trained men. Fifteen resistance-trained men (age: 27±5 years, height: 173±9 cm, total body mass: 81±10 kg) were assigned to this study. Three resistance exercises (FR, DR, and LR) were tested isometrically at three different shoulder joint angles (0°, 45°, and 90°). Peak force (PF) and myoelectric activity (iEMG) were measured for all exercises and shoulder joint angles. A two-way repeated-measures ANOVA (3x3) was used to test differences between exercises (FR, DR, and LR) and shoulder joint angles (0°, 45°, and 90°) for PF. A three-way repeated-measures ANOVA (2x3x3) was used to test differences between muscle groups (AD and MD), exercises (LR, DR, and FR), and shoulder joint angles (0°, 45°, and 90°) for iEMG. All RT exercises presented similar levels of force production and myoelectric activity (AD and MD) regardless of the specific plane of motion (p>0.05). However, the shoulder joint position affected the force production and AD activity without changes for MD.
Copyright (c) 2025 Willy A. Gomes, Josinaldo J. da Silva, Roberto A. Magalhaes, Luis F.M. Teixeira, Rafael C. Paulino, Paulo H. Marchetti https://creativecommons.org/licenses/by/4.0