Effect of Multi-Ingredient Preworkout Supplementation on Repeated Sprint Performance in Recreationally Active Men and Women
Gonzalez, AM, Pinzone, AG, Bram, J, Salisbury, JL, Lee, S, and Mangine, GT. Effect of multi-ingredient preworkout supplementation on repeated sprint performance in recreationally active men and women. J Strength Cond Res 34(4): 918–923, 2020—The purpose of this investigation was to examine the effects of acute supplementation of a multi-ingredient preworkout supplement (MIPS), containing a proprietary blend of ancient peat and apple extracts, creatine monohydrate, taurine, ribose, and magnesium, on sprint cycling performance. Seventeen recreationally active men and women (23.2 ± 5.9 years; 172.9 ±...
Source: Journal of Strength and Conditioning Research - March 25, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of Velocity Loss During Body Mass Prone-Grip Pull-up Training on Strength and Endurance Performance
This study aimed to analyze the effects of 2 pull-up (PU) training programs that differed in the magnitude of repetition velocity loss allowed in each set (25% velocity loss “VL25” vs. 50% velocity loss “VL50”) on PU performance. Twenty-nine strength-trained men (age = 26.1 ± 6.3 years, body mass [BM] = 74.2 ± 6.4 kg, and 15.9 ± 4.9 PU repetitions to failure) were randomly assigned to 2 groups: VL25 (n = 15) or VL50 (n = 14) and followed an 8-week (16 sessions) velocity-based BM prone-grip PU training program. Mean propulsive velocity (MPV) was monitored in all repetitions. Asse...
Source: Journal of Strength and Conditioning Research - March 25, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Postactivation Potentiation in Blood Flow–Restricted Complex Training
Cleary, CJ and Cook, SB. Postactivation potentiation in blood flow–restricted complex training. J Strength Cond Res 34(4): 905–910, 2020—Complex training uses a high-load (HL) resistance exercise to elicit postactivation potentiation (PAP) that is typically observed through enhanced plyometric performance. Blood flow–restricted (BFR) resistance exercise uses low loads to induce similar muscular adaptations to HL resistance exercise; however, the efficacy and feasibility of BFR complex training are unknown. Fifteen college-aged men (mean ± SD; age: 20.3 ± 0.9 years; relative back-squat ...
Source: Journal of Strength and Conditioning Research - March 25, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of an Acute Strength and Conditioning Training Session on Dual-Energy X-Ray Absorptiometry Results
Lytle, JR, Stanelle, ST, Kravits, DM, Ellsworth, RL, Martin, SE, Green, JS, and Crouse, SF. Effects of an acute strength and conditioning training session on dual-energy x-ray absorptiometry results. J Strength Cond Res 34(4): 901–904, 2020—The purpose of this study was to determine whether an athletic strength and conditioning (S&C) session will alter body composition estimates of a dual-energy x-ray absorptiometry (DXA) scan. Twenty-two strength-trained individuals (15 men, 7 women, 24 ± 2 years, 174.2 ± 8.5 cm, 83.5 ± 15.0 kg) volunteered to participate in the study. Each subject und...
Source: Journal of Strength and Conditioning Research - March 25, 2020 Category: Sports Medicine Tags: Research Note Source Type: research

XII INTERNATIONAL SYMPOSIUM IN STRENGTH TRAINING & IronFEMME STUDY
No abstract available (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Abstracts Source Type: research

Effects of High-Intensity Interval Training in Combat Sports: A Systematic Review with Meta-Analysis
Vasconcelos, BB, Protzen, GV, Galliano, LM, Kirk, C, and Del Vecchio, FB. Effects of high-intensity interval training in combat sports: A systematic review with meta-analysis. J Strength Cond Res 34(3): 888–900, 2020—Combat sports (CS) are intermittent by nature and high-intensity interval training (HIIT) has been used as a tool to maintain and improve physical fitness among CS athletes. The aim of this study was to perform a systematic review and meta-analysis about chronic effects of HIIT in CS athletes. An electronic search was performed in PubMed, Science Direct, and Google Scholar using the following Boole...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Differences in Maturity, Morphological, and Fitness Attributes Between the Better- and Lower-Ranked Male and Female U-14 Portuguese Elite Regional Basketball Teams
In conclusion, speed and upper limb strength appear to be the physical attributes associated with better team performance in youth basketball. Coaches should be aware of the relationship between the improvement of these physical attributes and the teaching-learning process of the basketball game. (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Exercise Supervision Is Important for Cardiometabolic Health Improvements: A 16-Week Randomized Controlled Trial
Hunter, JR, Gordon, BA, Bird, SR, and Benson, AC. Exercise supervision is important for cardiometabolic health improvements: a 16-week randomized controlled trial. J Strength Cond Res 34(3): 866–877, 2020—Exercise supervision enhances health and fitness improvements in clinical populations compared with unsupervised or home-based exercise, but effects of supervision type are unknown in healthy employees. Eighty-five Australian university employees (62 females; mean ± SD 43.2 ± 9.8 years) were randomized to personal (1:1; SUP, n = 28), nonpersonal (typical gym-based; NPS, n = 28) supervision or uns...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Acceleration Pattern and Neuromuscular Response of the Spine and Ankle During the Limits-of-Stability Test
This study aimed to explore the acceleration amplitude, frequency, and electromyography (EMG) activity at the spine, pelvis, and lower extremities under various platform-stability settings. Thirty two young adults (16 men and 16 women) were recruited from a university in Taiwan. A balance system for limits-of-stability testing was used with 2 platform stability settings (i.e., level 4 and static). An inertial motion system and a telemetry EMG system were used to record kinematic and EMG data. Consequently, compared with the level 4 setting, the static-level setting required greater thoracic lateral flexion, pelvic course, ...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Biochemical and Muscle Mechanical Postmarathon Changes in Hot and Humid Conditions
Gutiérrez-Vargas, R, Martín-Rodríguez, S, Sánchez-Ureña, B, Rodríguez-Montero, A, Salas-Cabrera, J, Gutiérrez-Vargas, JC, Simunic, B, and Rojas-Valverde, D. Biochemical and muscle mechanical postmarathon changes in hot and humid conditions. J Strength Cond Res 34(3): 847–856, 2020—The aim of this study was to compare biochemical changes and mechanical changes in the lower-limb muscles before and after a marathon race in hot and humid conditions. Eighteen healthy runners participated in a marathon at between 28 and 34° C and 81% humidity in Costa Rica. Serum m...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Effect of a Hamstring Flexibility Program Performed Concurrently During an Elite Canoeist Competition Season
In conclusion, it is suggested that a supervised hamstring flexibility program performed concurrently during a canoeist competition season can produce an increase in the knee joint ROM and trunk flexion, without negative repercussions in contractile and neuromuscular capacities, maximum power, and average velocity in lower limbs. (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of Pre-race Apneas on 400-m Freestyle Swimming Performance
This study aimed to establish whether a series of 3 apneas before a 400-m freestyle time-trial affected swimming performance when compared with and combined with a warm-up. Nine (6 males and 3 females) regional to national standard swimmers completed four 400-m freestyle time-trials in 4 randomized conditions: without warm-up or apneas (CON), warm-up only (WU), apneas only (AP), and warm-up and apneas (WUAP). Time-trial performance was significantly improved after WUAP (275.79 ± 12.88 seconds) compared with CON (278.66 ± 13.31 seconds, p = 0.035) and AP (278.64 ± 4.10 seconds, p = 0.015). However, ther...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Monitoring Age-Group Swimmers Over a Training Macrocycle: Energetics, Technique, and Anthropometrics
Zacca, R, Azevedo, R, Chainok, P, Vilas-Boas, JP, Castro, FAdS, Pyne, DB, and Fernandes, RJ. Monitoring age-group swimmers over a training macrocycle: energetics, technique, and anthropometrics. J Strength Cond Res 34(3): 818–827, 2020—The aim of this study was to quantify changes and contributions of energetic, technique, and anthropometric profiles across the first training macrocycle (16-week) in a traditional 3-peak swimming season. Twenty-four age-group swimmers (10 boys and 14 girls age 14.4 ± 0.9 years) of equal maturational stage were monitored through a 400-m test in front crawl (T400). Energeti...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Influence of Situational Variables, Team Formation, and Playing Position on Match Running Performance and Social Network Analysis in Brazilian Professional Soccer Players
Aquino, R, Carling, C, Palucci Vieira, LH, Martins, G, Jabor, G, Machado, J, Santiago, P, Garganta, J, and Puggina, E. Influence of situational variables, team formation, and playing position on match running performance and social network analysis of brazilian professional soccer players. J Strength Cond Res 34(3): 808–817, 2020—The purpose of this study was to investigate the independent and interactive effects of situational variables, opposition team formation, and playing position on running performance and network analysis in Brazilian professional soccer players (n = 22). Global positioning system techno...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Nordic Hamstring Strength of Highly Trained Youth Football Players and Its Relation to Sprint Performance
Markovic, G, Sarabon, N, Boban, F, Zoric, I, Jelcic, M, Sos, K, and Scappaticci, M. Nordic hamstring strength of highly trained youth football players and its relation to sprint performance. J Strength Cond Res 34(3): 800–807, 2020—We aimed to characterize Nordic hamstring (NH) strength and bilateral NH strength asymmetry in highly trained youth footballers and to investigate the relationship between NH strength and sprint performance. Twenty-two adult and 133 highly trained youth footballers in the age groups U12–U18 participated in this study. Eccentric hamstring strength was assessed using the NH devic...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Functional Basis of Asymmetrical Lower-Body Skeletal Morphology in Professional Australian Rules Footballers
Hart, NH, Newton, RU, Weber, J, Spiteri, T, Rantalainen, T, Dobbin, M, Chivers, P, and Nimphius, S. Functional basis of asymmetrical lower-body skeletal morphology in elite Australian footballers. J Strength Cond Res 34(3): 791–799, 2020—Bone strength is a product of its material and structural properties and is highly responsive to mechanical load. Given the measureable and adaptable features of bone, and thus relevance to medical screening, injury prevention, and injury management in athletes, this study describes the lower-body skeletal morphology of professional Australian rules footballers. Using a cross-s...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Salivary IgA as a Predictor of Upper Respiratory Tract Infections and Relationship to Training Load in Elite Rugby Union Players
In conclusion, sIgA may be a useful predictor for determining the likelihood of players contracting an URTI. This will allow the coach to make informed decisions on training status, helping reduce the risk of players missing training, which may have performance decrements. Coaches will benefit from the fast, easy, and instant results available, to analyze a player's immune function. (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

A Comparison of the National Football League's Annual National Football League Combine 1999–2000 to 2015–2016
This study was conducted with (N = 1,263) subjects from the 1999–2000 (99–00) NFL Combines (n = 635) and the 2015–2016 (15–16) NFL Combines (n = 628) separated by position. Data were collected for height, body mass, 40-yd (36.58 m) dash, NFL 225 lb. (102.06 kg) repetitions test, vertical jump (VJ), broad jump (BJ), pro-agility shuttle, and 3-cone drill. Statistical significance between the years for all subjects participating in the NFL Combine was found for the 40-yd dash (99–00: mean ± SD = 4.85 ± 3.2; 15–16: 4.80 ± 3.5; p = 0.002) and VJ (99–00 = 82.04 &plus...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

The Effect of Aspartate and Sodium Bicarbonate Supplementation on Muscle Contractile Properties Among Trained Men
Farney, TM, MacLellan, MJ, Hearon, CM, Johannsen, NM, and Nelson, AG. The effect of aspartate and sodium bicarbonate supplementation on muscle contractile properties among trained men. J Strength Cond Res 34(3): 763–770, 2020—The focus of this investigation was to examine the effects of aspartate and NaHCO3 supplementation on muscle contractile properties within trained men. Eleven men (21.9 ± 1.5 years) ingested supplementation as 4 conditions all separated by 1 week and included the following: placebo (PLA), L-aspartate (12.5 mg) (ASP), NaHCO3 (0.3 g·kg−1) (SBC), or combination of ASP and ...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

The Effects of British Army Footwear on Ground Reaction Force and Temporal Parameters of British Army Foot Drill
Rawcliffe, AJ, Graham, SM, Simpson, RJ, Moir, GL, Martindale, RJ, Psycharakis, SG, and Connaboy, C. The effects of British Army footwear on ground reaction force and temporal parameters of British Army foot drill. J Strength Cond Res 34(3): 754–762, 2020—High rates of occupational training-related lower-limb musculoskeletal (MSK) overuse injuries are reported for British Army recruits during basic training. Foot drill is a repetitive impact loading occupational activity and involves striking the ground violently with an extended-knee (straight-leg) landing. Foot drill produces vertical ground reaction force (vG...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of Periodized vs. Nonperiodized Resistance Training on Army-Specific Fitness and Skills Performance
This study investigated the effects of periodized resistance training (PRD) and nonperiodized resistance training (NPRD) on army-specific fitness and skills performance measures. Forty-nine serving members of the Australian Army were randomly assigned to 1 of 3 training groups: PRD, NPRD, or no-resistance training (NRT). Resistance training (RT) was performed during PRD and NPRD twice a week for 9 weeks, over a 15-week period, as part of a structured strength and conditioning program. Baseline, mid- and post-testing measures included anthropometric, strength, and army-specific outcome measures. Results indicated that parti...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Test-Retest Reliability of a Commercial Linear Position Transducer (GymAware PowerTool) to Measure Velocity and Power in the Back Squat and Bench Press
In conclusion, GYM provides practitioners with reliable kinematic information in the back squat and bench press, at least with loads of 40–90% of 1RM. This suggests that strength and conditioning coaches can use the velocity data to regulate training load according to daily readiness and target specific components of the force-velocity curve. However, caution should be taken when measuring movement velocity at loads (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Potentiating Response to Drop-Jump Protocols on Sprint Acceleration: Drop-Jump Volume and Intrarepetition Recovery Duration
Byrne, PJ, Moody, JA, Cooper, SM, Callanan, D, and Kinsella, S. Potentiating response to drop-jump protocols on sprint acceleration: drop-jump volume and intrarepetition recovery duration. J Strength Cond Res 34(3): 717–727, 2020—The purpose of this study was to investigate the postactivation potentiation response first to bounce drop jump (BDJ) volume; second, BDJ intrarepetition recovery duration and recovery duration between BDJs and 20-meter (including 5- and 10-m split times) sprint performance. The study was undertaken in 2 parts, the first part compared different volumes of BDJs and the second part compa...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Evaluating the Effects of a Novel Neuromuscular Neck Training Device on Multiplanar Static and Dynamic Neck Strength: A Pilot Study
Versteegh, TH, Dickey, JP, Emery, CA, Fischer, LK, MacDermid, JC, and Walton, DM. Evaluating the effects of a novel neuromuscular neck training device on multiplanar static and dynamic neck strength: A pilot study. J Strength Cond Res 34(3): 708–716, 2020—The neck serves an important function in damping the transference of acceleration forces between the head and the trunk, such as that occurring during contact sports or motor vehicle collisions. An inability to adequately dissipate forces has been proposed as a potential mechanism for clinical conditions such as whiplash or concussion, but current approaches t...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Oxygen Uptake, Heart Rate, and Lactate Responses for Continuous Forward Running and Stop-and-Go Running With and Without Directional Changes
Bekraoui, N, Boussaidi, L, Cazorla, G, and Léger, L. Oxygen uptake, heart rate, and lactate responses for continuous forward running and stop-and-go running with and without directional changes. J Strength Cond Res 34(3): 699–707, 2020—The purpose of this study is to measure and quantify the differences for the gross oxygen uptake (V[Combining Dot Above]O2), heart rate (HR), and blood lactate ([LA]) responses to various modes of in-line running. Twelve healthy participants did an indirect continuous multistage field test to determine the maximal aerobic speed (MAS) before randomly performing in separate ...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of Traditional and Vascular Restricted Strength Training Program With Equalized Volume on Isometric and Dynamic Strength, Muscle Thickness, Electromyographic Activity, and Endothelial Function Adaptations in Young Adults
This study was approved by the ethics committee. Flow-mediated dilation showed a significant difference in baseline and post-training in the LI-BFR group (4.44 ± 0.51 vs. 6.35 ± 2.08 mm, respectively). For nitrite/nitrate concentrations only, there was a significant difference when comparing pre- and post-acute exercise in both groups. The torque and rep. Sixty percent 1 repetition maximum had improvements in both groups. There were differences between groups only in isometric delta EF and isokinetic delta KE (EF 3.42 ± 5.09 and 9.61 ± 7.52 N·m; KE 12.78 ± 25.61 and 42.69 ± ...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Comparison of Multifrequency Bioelectrical Impedance vs. Dual-Energy X-ray Absorptiometry for Assessing Body Composition Changes After Participation in a 10-Week Resistance Training Program
Schoenfeld, BJ, Nickerson, BS, Wilborn, CD, Urbina, SL, Hayward, SB, Krieger, J, Aragon, AA, and Tinsley, G. Comparison of multifrequency bioelectrical impedance vs. dual-energy x-ray absorptiometry for assessing body composition changes after participation in a 10-week resistance training program. J Strength Cond Res 34(3): 678–688, 2020—The purpose of this study was to assess the ability of multifrequency bioelectrical impedance analysis (MF-BIA) to determine alterations in total and segmental body composition across a 10-week resistance training (RT) program in comparison with the criterion reference dual-en...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Assessment of Loaded Squat Jump Height With a Free-Weight Barbell and Smith Machine: Comparison of the Takeoff Velocity and Flight Time Procedures
Pérez-Castilla, A, McMahon, JJ, Comfort, P, and García-Ramos, A. Assessment of loaded squat jump height with a free-weight barbell and Smith machine: comparison of the takeoff velocity and flight time procedures. J Strength Cond Res 34(3): 671–677, 2020—The aims of this study were to compare the reliability and magnitude of jump height between the 2 standard procedures of analyzing force platform data to estimate jump height (takeoff velocity [TOV] and flight time [FT]) in the loaded squat jump (SJ) exercise performed with a free-weight barbell and in a Smith machine. Twenty-three collegiate men (...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Mechanical and Metabolic Responses to Traditional and Cluster Set Configurations in the Bench Press Exercise
This study aimed to compare mechanical and metabolic responses between traditional (TR) and cluster (CL) set configurations in the bench press exercise. In a counterbalanced randomized order, 10 men were tested with the following protocols (sets × repetitions [inter-repetition rest]): TR1: 3 × 10 (0-second), TR2: 6 × 5 (0-second), CL5: 3 × 10 (5-second), CL10: 3 × 10 (10-second), and CL15: 3 × 10 (15-second). The number of repetitions (30), interset rest (5 minutes), and resistance applied (10 repetition maximum) were the same for all set configurations. Movement velocity and blood lacta...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of a 12-Week Training Program on Isometric and Dynamic Force-Time Characteristics in Pre– and Post–Peak Height Velocity Male Athletes
Dobbs, IJ, Oliver, JL, Wong, MA, Moore, IS, and Lloyd, RS. Effects of a 12-week training program on isometric and dynamic force-time characteristics in pre– and post–peak height velocity male athletes. J Strength Cond Res 34(3): 653–662, 2020—Literature shows that training children and adolescents can enhance strength and power irrespective of their stage of development; however, the development of the kinetic variables that underpin strength and power performance are typically unreported in youth training studies. Twenty-four pre– and 14 post–peak height velocity (PHV) male athletes wer...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

One Week of L-Citrulline Supplementation Improves Performance in Trained Cyclists
This study used a randomized, double-blind, crossover design to test whether chronic supplementation with pure CIT improves cycling performance over a maltodextrin placebo (PLAC). Nine trained male cyclists (24 ± 3 years; 181 ± 7 cm; 76 ± 13 kg; 4.18 ± 0.51 L·min−1 V[Combining Dot Above]O2max) completed two 7-day supplementation periods (6 g·d−1 of CIT or PLAC) separated by a 7-day washout. Subjects consumed the final 6-g dose 2 hours before the cycling performance evaluation, which consisted of a 40-km time trial (TT) followed by a supramaximal sprint repeat task (SRT)...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Tracking In-Match Movement Demands Using Local Positioning System in World-Class Men's Ice Hockey
Douglas, AS and Kennedy, CR. Tracking in-match movement demands using local positioning system in world-class men's ice hockey. J Strength Cond Res 34(3): 639–646, 2020—While the global positioning system has been used in field sports for a decade, local positioning systems are newly available in indoor sports for the tracking of velocity and distance during competition. World-class male ice hockey players (n = 20) were monitored during 5 international matches. Speed and distance outputs were analyzed to determine the differences between positions, periods, and in-shift demands. Defense had a difference between...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

A 4-Year Profile of Game Demands in Elite Women's Division I College Basketball
Ransdell, LB, Murray, T, Gao, Y, Jones, P, and Bycura, D. A 4-year profile of game demands in elite women's Division I college basketball. J Strength Cond Res 34(3): 632–638, 2020—Workload for a Division I women's collegiate basketball team (0.817 win percentage) was examined by: (a) season, (b) player position, and (c) game outcome (wins vs. losses). Female athletes (n = 6, mean 19.7 ± 1.5 years, at beginning of study) wore Catapult S5 units during 91.8% of games over a 4-year period. Average PlayerLoad, PlayerLoad per minute (PL·min−1), high inertial movement analysis (high-IMA), and jumps...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Quantitative Relationships Between Individual Lower-Limb Muscle Volumes and Jump and Sprint Performances of Basketball Players
Xie, T, Crump, KB, Ni, R, Meyer, CH, Hart, JM, Blemker, SS, and Feng, X. Quantitative relationships between individual lower-limb muscle volumes and jump and sprint performances of basketball players. J Strength Cond Res 34(3): 623–631, 2020—Lower body skeletal muscles play an essential role in athletic performance; however, because of the difficulty in obtaining detailed information of each individual muscle, the quantitative relationships between individual muscle volumes and performance are not well studied. The aim of this study was to accurately measure individual muscle volumes and identify the muscles wi...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Listening to Fast-Tempo Music Delays the Onset of Neuromuscular Fatigue
Centala, J, Pogorel, C, Pummill, SW, and Malek, MH. Listening to fast-tempo music delays the onset of neuromuscular fatigue. J Strength Cond Res 34(3): 617–622, 2020—Studies determining the effect of music on physical performance have primarily focused on outcomes such as running time to exhaustion, blood lactate, or maximal oxygen uptake. The electromyographic fatigue threshold (EMGFT) is determined through a single incremental test and operationally defined as the highest exercise intensity that can be sustained indefinitely without an increase in EMG activity of the working muscle. To date, no studies have e...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Examination of Sleep and Injury Among College Football Athletes
Burke, TM, Lisman, PJ, Maguire, K, Skeiky, L, Choynowski, JJ, CapaldiII, VF, Wilder, JN, Brager, AJ, and Dobrosielski, DA. Examination of sleep and injury among college football athletes. J Strength Cond Res 34(3): 609–616, 2020—The purpose of this study was to characterize subjective sleep metrics in collegiate football players at the start of the season, determine the relationship between preseason subjective sleep measures and in-season objective sleep characteristics, and examine the association between subjective and objective sleep metrics and incidence of time-loss injury during the competitive season. N...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of Whole-Body Vibration Training and Blood Flow Restriction on Muscle Adaptations in Women: A Randomized Controlled Trial
Centner, C, Ritzmann, R, Gollhofer, A, and König, D. Effects of whole-body vibration training and blood flow restriction on muscle adaptations in women: a randomized controlled trial. J Strength Cond Res 34(3): 603–608, 2020—The purpose of the present randomized controlled trial was to investigate potential synergistic effects of whole-body vibration (WBV) training combined with blood flow restriction (BFR) on muscle mass and strength, and jump performance. Fifty healthy women (26.1 ± 4.6 years) were randomly allocated to one of the following experimental groups: WBV training combined with BFR (WBV ...
Source: Journal of Strength and Conditioning Research - February 20, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Multiple-Joint Isokinetic Dynamometry: A Critical Review
Dvir, Z and Müller, S. Multiple-joint isokinetic dynamometry: a critical review. J Strength Cond Res 34(2): 587–601, 2020—Angular isokinetic dynamometry (AID) is widely regarded as the gold standard for dynamic muscle performance testing. Based on the rotational movement of its actuator, AID targets “single-joint” (knee, shoulder, hip, etc.) configurations namely measurement of muscle potential while it moves the lever arm-limb assembly ostensibly around a single fixed axis. On the other hand, the application of multiple-joint isokinetic dynamometry (MID) is relatively narrow, both in research ...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Brief Review Source Type: research

Prediction of Gymnastics Physical Profile Through an International Program Evaluation in Women Artistic Gymnastics
Nassib, SH, Mkaouer, B, Riahi, SH, Wali, SM, and Nassib, S. Prediction of gymnastics physical profile through an international program evaluation in women artistic gymnastics. J Strength Cond Res 34(2): 577–586, 2020—The purpose of this study was to investigate the most appropriate aptitudes for top-level sporting results to identify physical profile of talent identified women's artistic gymnastics (WAG). Forty-eight women's artistic gymnasts in the provincial team (age 11.12 ± 1.22 years; height 1.35 ± 0.04 m; body mass 28.5 ± 4.04 kg) voluntarily participated in this study. Anthropometric...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Performance Differences Between the Sexes in the Boston Marathon From 1972 to 2017
We examined trends in participation and performance in the Boston Marathon from 1972 to 2017. A total of 371,250 different finishers (64% men) and 553,890 observations—with 187,998 (34%) being of women and 365,892 (66%) of men—were analyzed using Generalized Additive Mixed Models. The number of finishers increased over the years. Female participation started at 2.81% in 1972 and reached 45.68% in 2016. Considering all finishers, men (03:38:42 ± 00:41:43 h:min:s) were overall faster than women (04:03:28 ± 00:38:32 h:min:s) by 10.7%. Average performance worsened over the years, but the differences b...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Quantification of the Perceived Training Load in Young Female Basketball Players
Otaegi, A and Los Arcos, A. Quantification of the perceived training load in young female basketball players. J Strength Cond Res 34(2): 559–565, 2020—The purposes of this study were (a) to compare training session, match, and weekly perceived training load (TL) between U15 and U16 female basketball players and (b) within the teams, to assess the relationship between perceived TL and the changes in physical fitness performance during an in-season 9-week period. Twenty-one female players from U15 and U16 female teams from the same Spanish club participated in the study. Before and after the study, players were t...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Countermovement Jump Reliability Performed With and Without an Arm Swing in NCAA Division 1 Intercollegiate Basketball Players
Heishman, AD, Daub, BD, Miller, RM, Freitas, EDS, Frantz, BA, and Bemben, MG. Countermovement jump reliability performed with and without an arm swing in NCAA Division 1 intercollegiate basketball players. J Strength Cond Res 34(2): 546–558, 2020—The countermovement jump (CMJ) is routinely used in athlete performance to quantify adaptions to training, as well as monitor neuromuscular readiness and fatigue. However, controversy remains in whether to incorporate an arm swing during the CMJ (CMJ AS) or keep the hands placed on the hips (CMJ NAS). Incorporating the arms provides a higher degree of sport-specificity...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Influence of Weekly Workload on Physical, Biochemical and Psychological Characteristics in Professional Rugby Union Players Over a Competitive Season
This study aimed to (a) quantify the physical workload (P-WL) during training and games throughout the professional rugby season and (b) analyze the influence of the season period and weekly-WL, at short (acute) and moderate (chronic) terms, on physical, biochemical, and psychological responses during the season. Physiological (physical and biochemical) responses to P-WL were analyzed by examining changes in the individual Z score of the Yo-Yo intermittent recovery test (YYIRT), submaximal aerobic tests (5′/5′-test), strength tests, countermovement jump tests, blood sampling, and “recovery-stress” s...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

In-Season Integrative Neuromuscular Strength Training Improves Performance of Early-Adolescent Soccer Athletes
Panagoulis, C, Chatzinikolaou, A, Avloniti, A, Leontsini, D, Deli, CK, Draganidis, D, Stampoulis, T, Oikonomou, T, Papanikolaou, K, Rafailakis, L, Kambas, A, Jamurtas, AZ, and Fatouros, IG. In-season integrative neuromuscular strength training improves performance of early-adolescent soccer athletes. J Strength Cond Res 34(2): 516–526, 2020—Although forms of integrative neuromuscular training (INT) are used extensively for injury prevention and treatment, no information exists about its effects on performance of adolescent athletes. We investigated the effects of an in-season INT intervention on performance of ...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Normative Data and Physical Determinants of Multiple Sprint Sets in Young Soccer Players Aged 11–18 Years: Effect of Maturity Status
Selmi, MA, Sassi, RH, Yahmed, MH, Giannini, S, Perroni, F, and Elloumi, M. Normative data and physical determinants of multiple sprint sets in young soccer players aged 11–18 years: Effect of maturity status. J Strength Cond Res 34(2): 506–515, 2020—The aims of the study were: (a) to establish normative data for repeated-sprint sets (RSS) test based on the maturity status (age at peak height velocity [PHV]) and (2) to investigate the relationship between anthropometrical variables (stature, sitting height, body mass, and body fat percentage), RSS (2 × 5 × 20 m with 15-second recovery between s...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Age-Matched Z-Scores for Longitudinal Monitoring of Center of Pressure Speed in Single-Leg Stance Performance in Elite Male Youth Soccer Players
Huurnink, A, Fransz, DP, de Boode, VA, Kingma, I, and van Dieën, JH. Age-matched z-scores for longitudinal monitoring of center of pressure speed in single-leg stance performance in elite male youth soccer players. J Strength Cond Res 34(2): 495–505, 2020—Coordination of corrective motor actions is considered important for soccer performance and injury prevention. A single-leg stance (SLS) test assesses the integrity and proficiency of the sensorimotor control system, quantified by center of pressure averaged speed (COPspeed). We aimed to provide age-matched z-scores for COPspeed in elite male youth soccer...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

The Arrowhead Agility Test: Reliability, Minimum Detectable Change, and Practical Applications in Soccer Players
Rago, V, Brito, J, Figueiredo, P, Ermidis, G, Barreira, D, and Rebelo, A. The arrowhead agility test: Reliability, minimum detectable change, and practical applications in soccer players. J Strength Cond Res 34(2): 483–494, 2020—Four independent studies were conducted to examine the utility of the arrowhead agility test (AAT) to measure change of direction (COD) capacity in soccer players, specifically, (a) intersession reliability and minimum detectable change (n = 24); (b) power-dependent abilities associated with AAT performance (n = 56); and (c) fatigue sensitivity (n = 20); differences between competitive ...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

How to Improve Change-of-Direction Speed in Junior Team Sport Athletes—Horizontal, Vertical, Maximal, or Explosive Strength Training?
Keller, S, Koob, A, Corak, D, von Schöning, V, and Born, DP. How to improve change-of-direction speed in junior team sport athletes—Horizontal, vertical, maximal, or explosive strength training? J Strength Cond Res 34(2): 473–482, 2020—The purpose of the study was to compare the effects of 4 different training methods on change-of-direction (COD) speed in junior team sport athletes. Specifically, we investigated whether horizontal load training incorporating lateral acceleration and deceleration would induce superior performance adaptations with respect to COD speed, compared with common vertically o...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Sprint Training on a Treadmill vs. Overground Results in Modality-Specific Impact on Sprint Performance but Similar Positive Improvement in Body Composition in Young Adults
Dorgo, S, Perales, JJ, Boyle, JB, Hausselle, J, and Montalvo, S. Sprint training on a treadmill vs. overground results in modality-specific impact on sprint performance but similar positive improvement in body composition in young adults. J Strength Cond Res 34(2): 463–472, 2020—The effects of different sprint training modalities on body composition are not yet known, and the effectiveness of using motorized treadmills for sprint training is yet to be assessed accurately. The following study investigated the effects of motorized treadmill and overground training on sprint performance and body composition. Sixty...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Influence of Menthol on Recovery From Exercise-Induced Muscle Damage
This study assessed the influence of menthol, a cold receptor agonist, on recovery from exercise-induced muscle damage (EIMD). Forty-seven healthy males were allocated to a Control (CON, n = 18), Placebo (P, n = 14), or 4.0% Menthol (M, n = 15) condition. Participants were familiarized with a testing battery (TB) including: perception of lower-body muscle soreness, hip flexion/abduction range of motion, vertical jump (VJ), and the agility T-test. Muscle damage was induced on day 1 using 40 × 15-m sprints with a 5-m deceleration zone. The TB immediately followed this and was repeated once-daily for 5 days. Over this t...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research