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

Effect of Acute Bouts of Volume-Matched High-Intensity Resistance Training Protocols on Blood Glucose Levels
Monroe, JC, Naugle, KM, and Naugle, KE. Effect of acute bouts of volume-matched high-intensity resistance training protocols on blood glucose levels. J Strength Cond Res 34(2): 445–450, 2020—Resistance exercise has the capability to alter glucose metabolism in healthy adults; however, to what extent single sessions of varying intensities of resistance exercise affect capillary glucose levels is not completely understood. The purpose of this study was to compare the effect of different resistance training intensities on capillary blood glucose levels in healthy adults. Thirteen resistance-trained men (age 24.4 &...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Test-Retest Reliability Between Free Weight and Machine-Based Movement Velocities
Miller, RM, Freitas, EDS, Heishman, AD, Koziol, KJ, Galletti, BAR, Kaur, J, and Bemben, MG. Test-retest reliability between free weight and machine-based movement velocities. J Strength Cond Res 34(2): 440–444, 2020—Several devices are available to measure muscular power through velocity measurement, including the Tendo FitroDyne. The ability for such devices to produce consistent results is still questioned, and the reproducibility of measurement between free weight and machine exercise has yet to be examined. Therefore, the aim of this investigation was to determine the test-retest reliability for barbell vel...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Yoga Breathing Techniques Have No Impact on Isokinetic and Isoinertial Power
Wooten, SV, Cherup, N, Mazzei, N, Patel, S, Mooney, K, Rafiq, A, and Signorile, JF. Yoga breathing techniques have no impact on isokinetic and isoinertial power. J Strength Cond Res 34(2): 430–439, 2020—As an exercise discipline, yoga incorporates breathing (pranayama) and posture (asana) techniques to facilitate improvements in flexibility, strength, and meditation. Both techniques have been used to enhance muscular strength and power output. The purpose of this study was to determine the effects of various yoga breathing techniques on lower-limb power output. Thirty-two individuals (15 men and 17 women) parti...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Physiological Responses of a Jaw-Repositioning Custom-Made Mouthguard on Airway and Their Effects on Athletic Performance
Martins, RS, Girouard, P, Elliott, E, and Mekary, S. Physiological responses of a jaw repositioning custom-made mouthguard on airway and their effects on athletic performance. J Strength Cond Res 34(2): 422–429, 2020—Advanced dental techniques such as jaw-repositioning have shown to increase lower body muscular power such as vertical jump, but its effects on acceleration and speed have not been studied. Similarly, jaw repositioning is commonly used to increase airways volume and ventilation in a special population (i.e., obstructive sleep apnea); however, its ergogenic effects on aerobic performance have yet no...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Physical Fitness and Anthropometric Values Among Lithuanian Primary School Children: Population-Based Cross-Sectional Study
Emeljanovas, A, Mieziene, B, Cesnaitiene, VJ, Fjortoft, I, and Kjønniksen, L. Physical fitness and anthropometric values among Lithuanian primary school children: population-based cross-sectional study. J Strength Cond Res 34(2): 414–421, 2020—The purpose of the current study was to derive representative reference scores on anthropometric measures and test scores for the musculoskeletal, motor, and cardiorespiratory fitness of Lithuanian primary school children according to age and sex. This cross-sectional design study included 3,456 Lithuanian first- to fourth-grade children from age 6 to 10 years. Phy...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of Seasonal Training Load on Performance and Illness Symptoms in Water Polo
Brisola, GMP, Claus, GM, Dutra, YM, Malta, ES, de Poli, RAB, Esco, MR, and Zagatto, AM. Effects of seasonal training load on performance and illness symptoms in water polo. J Strength Cond Res 34(2): 406–413, 2020—The purpose of the study was to describe the training load distribution of a young female water polo team in different cycles of the season and verify its subsequent effects on specific fitness measured by the repeated sprints ability (RSA) test, aerobic endurance measured by the lactate minimum test, incidence and severity of upper respiratory tract infection (URTI) symptoms, and muscle damage marker...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Changes in Torque-Angle Profiles of the Hamstrings and Hamstrings-to-Quadriceps Ratio After Two Hamstring Strengthening Exercise Interventions in Female Hockey Players
Delextrat, A, Bateman, J, Ross, C, Harman, J, Davis, L, Vanrenterghem, J, and Cohen, DD. Changes in torque-angle profiles of the hamstrings and hamstrings-to-quadriceps ratio after two hamstring strengthening exercise interventions in female hockey players. J Strength Cond Res 34(2): 396–405, 2020—The aim of this study was to compare the effects of 2 hamstring strengthening interventions (Nordic hamstrings [NHE] vs. eccentric leg curl [ELC]) on the hamstring torque-angle profiles and functional hamstrings-to-quadriceps ratio (Hecc:Qcon) in female hockey players. Female university-level players were randomly all...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Sweat Loss and Fluid Intake of Female Varsity Ice Hockey Players During On-Ice Practices and Games
Bigg, JL, Gamble, ASD, Vermeulen, TF, Bigg, LM, and Spriet, LL. Sweat loss and fluid intake of female varsity ice hockey players during on-ice practices and games. J Strength Cond Res 34(2): 389–395, 2020—Sweat losses of ∼1.5–2% body mass (BM) during exercise impairs athletic performance in stop and go sports such as ice hockey. The study examined the pre-exercise hydration status, sweat loss, fluid and carbohydrate (CHO) intake, and sodium balance of female hockey players. Twenty-four female varsity hockey players were tested during 2 practices and 4 games. Data analyses were performed using a level ...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Relationship Among Biological Maturation, Physical Characteristics, and Motor Abilities in Youth Elite Soccer Players
Itoh, R and Hirose, N. Relationship among biological maturation, physical characteristics, and motor abilities in youth elite soccer players. J Strength Cond Res 34(2): 382–388, 2020—Studies investigating skeletal maturity and motor abilities in youth Asian elite soccer players are lacking. We aimed to investigate the cross-sectional relationship among skeletal age (SA), physical characteristics, and motor abilities in youth elite soccer players. Skeletal age is commonly used to estimate the maturity status of youth athletes using a hand-wrist radiograph. We enrolled 49 youth elite male soccer players (12.7 &pl...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Contextual Factors Influencing External and Internal Training Loads in Collegiate Men's Soccer
This study investigated factors influencing training loads (TL) in collegiate men's soccer. Total distance, high-speed running distance (>14.4 km·h−1), high-intensity heart-rate zone duration (HI HRZ,>70% heart rate relative to maximum), and session rating of perceived exertion were assessed daily from 107 male soccer players competing for 5 National Collegiate Athletics Association Division I teams. Differences between athlete role (starter and reserve), position (defender, midfielder, and forward), season phase (preseason, in-season, and postseason), days relative to match (MD-1 to MD-5+), days between...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Using an Inertial Device (WIMU PRO) to Quantify Neuromuscular Load in Running: Reliability, Convergent Validity, and Influence of Type of Surface and Device Location
This study tested (a) the reliability and validity of WIMU PRO accelerometers to measure PlayerLoad (PL) and (b) the influence of speed, inertial device location, and type of surface where the incremental test is performed. Twenty resistance-trained men (age: 27.32 ± 6.65 years; height: 1.74 ± 0.03 m; body mass: 68.96 ± 4.37 kg; and body mass index: 22.76 ± 1.11 kg·m−2) volunteered to participate in the study that lasted 5 weeks. Four progressive incremental tests were performed in treadmill and athletic track conditions. External load variable (PL) and physiological variables (hear...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Change in Lactate, Ammonia, and Hypoxanthine Concentrations in a 1-Year Training Cycle in Highly Trained Athletes: Applying Biomarkers as Tools to Assess Training Status
Włodarczyk, M, Kusy, K, Słomińska, E, Krasiński, Z, and Zieliński, J. Change in lactate, ammonia, and hypoxanthine concentrations in a 1-year training cycle in highly trained athletes: applying biomarkers as tools to assess training status. J Strength Cond Res 34(2): 355–364, 2020—The aim was to determine changes in biomarker (LA, NH3, purine metabolites) blood concentration during graded exercise and recovery throughout an annual training cycle in highly trained athletes of different training profiles. The study included 12 sprinters (SP, 21–30 years), 11 triathletes (TR, 20–31 years), 12 futs...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Can Backward Sled Towing Potentiate Sprint Performance?
The objectives of this study were to determine whether backward sled towing can elicit a postactivation potentiation response to enhance forward 5-m sprint performance and to determine whether sled loading through a reduction in velocity can elicit an improvement in 5-m sprint performance. A randomized design was used to examine the effects of forward and backward sled tow loading of 35 and 55% reduction of individual's maximal velocity (rVelmean) on 5-m sprint performance. Eighteen well-trained male subjects performed 4 intervention sessions (55% rVelmean backward; 55% rVelmean forward; 35% rVelmean backward; and 35% rVel...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Comparison of the Effects of Eccentric, Concentric, and Eccentric-Concentric Isotonic Resistance Training at Two Velocities on Strength and Muscle Hypertrophy
Ünlü, G, Çevikol, C, and Melekoğlu, T. Comparison of the effects of eccentric, concentric, and eccentric-concentric isotonic resistance training at two velocities on strength and muscle hypertrophy. J Strength Cond Res 34(2): 337–344, 2020—The aim of this study was to compare the effects of concentric, eccentric, and eccentric-concentric isotonic resistance training at both fast and slow velocities to determine whether contraction modality affects muscle strength and hypertrophy. Forty-one young, healthy males (mean age 21.1 ± 1.8 years; height 178.9 ± 6.1 cm; body mass 70.5 &plu...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Restricted Unilateral Ankle Dorsiflexion Movement Increases Interlimb Vertical Force Asymmetries in Bilateral Bodyweight Squatting
Crowe, MA, Bampouras, TM, Small, K, and Howe, LP. Restricted unilateral ankle dorsiflexion movement increases interlimb vertical force asymmetries in bilateral bodyweight squatting. J Strength Cond Res 34(2): 332–336, 2020—The purpose of this study was to investigate the effect of unilateral restrictions in ankle-dorsiflexion range of motion (DF-ROM) on interlimb vertical ground reaction force (vGRF) asymmetries. Twenty healthy and physically active volunteers (age 23 ± 3 years; height 1.72 ± 0.1 m; mass 74.9 ± 20.3 kg) performed 3 barefoot bodyweight squats (control condition) and with a 1...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Analysis of Freestyle Swimming Sprint Start Performance After Maximal Strength or Vertical Jump Training in Competitive Female and Male Junior Swimmers
Born, DP, Stöggl, T, Petrov, A, Burkhardt, D, Lüthy, F, and Romann, M. Analysis of freestyle swimming sprint start performance after maximal strength or vertical jump training in competitive female and male junior swimmers. J Strength Cond Res 34(2): 323–331, 2020—To investigate the freestyle swimming sprint start performance before and after 6 weeks of maximal strength compared with vertical jump training. With a between-group repeated-measure design, 21 junior swimmers (12 female and 9 male) competing in national and international championships performed 2 weekly sessions of either maximal strength ...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Acute Neuromuscular and Hormonal Responses to Different Exercise Loadings Followed by a Sauna
Rissanen, JA, Häkkinen, A, Laukkanen, J, Kraemer, WJ, and Häkkinen, K. Acute neuromuscular and hormonal responses to different exercise loadings followed by a sauna. J Strength Cond Res 34(2): 313–322, 2020—The purpose of this study was to investigate acute responses of endurance (E + SA), strength (S + SA), and combined endurance and strength exercise (C + SA) followed by a traditional sauna bath (70° C, 18% relative humidity) on neuromuscular performance and serum hormone concentrations. Twenty-seven recreationally physically active men who were experienced with taking a sauna participated in th...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Relationship Between Bench Press Strength and Punch Performance in Male Professional Boxers
This study investigated the relationship between punching performance and the velocity at which different loads were lifted during the bench press (BP) exercise in 12 professional boxers (age = 22.6 ± 4 years; height = 177.7 ± 5 cm; body mass 70.6 ± 6.43 kg; years of boxing experience = 6.5 ± 3.5 years; weight class = from light to super welterweight). To determine the maximal punching velocity (PVmax) during both rear arm (RA) and lead arm (LA) punching, an accelerometer (Crossbow; Willow Technologies, Sussex, United Kingdom) was placed inside the boxing glove while executing 3 jabs at a maxima...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Effect of Onset Threshold on Kinetic and Kinematic Variables of a Weightlifting Derivative Containing a First and Second Pull
This study sought to determine the effect of different movement onset thresholds on both the reliability and absolute values of performance variables during a weightlifting derivative containing both a first and second pull. Fourteen men (age: 25.21 ± 4.14 years; body mass: 81.1 ± 11.4 kg; and 1 repetition maximum [1RM] power clean: 1.0 ± 0.2 kg·kg−1) participated in this study. Subjects performed the snatch-grip pull with 70% of their power clean 1RM, commencing from the mid-shank, while isolated on a force platform. Two trials were performed enabling within-session reliability of depende...
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Original Research Source Type: research

Dr. Mike Greenwood: A Life of Coaching and Science
No abstract available (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - January 28, 2020 Category: Sports Medicine Tags: Editorial Source Type: research

Author's Response
No abstract available (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Manuscript Clarification Source Type: research

Manuscript Clarification for “Use of Mobile Applications to Collect Data in Sport, Health, and Exercise Science: A Narrative Review”
No abstract available (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Manuscript Clarification Source Type: research

Abstracts
No abstract available (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Abstracts Source Type: research

Hamstring-to-Quadriceps Torque Ratios of Professional Male Soccer Players: A Systematic Review
Baroni, BM, Ruas, CV, Ribeiro-Alvares, JB, and Pinto, RS. Hamstring-to-quadriceps torque ratios of professional male soccer players: A systematic review. J Strength Cond Res 34(1): 281–293, 2020—The goal of this review was to determine the isokinetic hamstring-to-quadriceps (H/Q) torque ratios of professional male soccer players. Systematic searches were independently carried out by 2 researchers in 7 electronic databases. Only studies with teams from the first or second national leagues were included. From these studies, we extracted the players' H/Q conventional (concentric/concentric) and/or functional (ecce...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Brief Review Source Type: research

Effects of Physical Exercise on the Expression of MicroRNAs: A Systematic Review
Silva, FCd, Iop, RdR, Andrade, A, Costa, VP, Gutierres Filho, PJB, and Silva, Rd. Effects of physical exercise on the expression of microRNAs: A systematic review 34(1): 270–280, 2020—Studies have detected changes in the expression of miRNAs after physical exercise, which brings new insight into the molecular control of adaptation to exercise. Therefore, the objective of the current systematic review of experimental and quasiexperimental studies published in the past 10 years was to assess evidence related to acute effects, chronic effects, and both acute and chronic effects of physical exercise on miRNA expres...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Brief Review Source Type: research

Reliability of Zephyr BioHarness Respiratory Rate at Rest, During the Modified Canadian Aerobic Fitness Test and Recovery
Nazari, G and MacDermid, JC. Reliability of Zephyr BioHarness respiratory rate at rest, during the modified Canadian Aerobic Fitness Test and recovery. J Strength Cond Res 34(1): 264–269, 2020—Technological innovations have led to the development of wearable physiological monitoring devices, such as the Zephyr BioHarness (ZB). It is necessary to establish the measurement properties of a device and to determine its reliability parameters, before its utilization. The purpose of current study was to determine the test-retest reliability of ZB respiratory rate variable at rest, during the modified Canadian Aerobic ...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Research Note Source Type: research

Minimal Detectable Change Thresholds and Responsiveness of Zephyr Bioharness and Fitbit Charge Devices
Nazari, G and MacDermid, JC. Minimal detectable change thresholds and responsiveness of zephyr bioharness and Fitbit Charge devices. J Strength Cond Res 34(1): 257–263, 2020—The aim of the current study was to define the minimal detectable change (MDC) thresholds for Zephyr Bioharness (ZB) and Fitbit Charge Heart Rate (FC-HR) variables and to establish the internal responsiveness of ZB and FC-HR devices in terms of their HR, respiratory rate variables, and number of steps taken variables, in a healthy sample of men and women at resting, submaximal activity and throughout recovery phases. A total of sixty partic...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Continuous Moderate-Intensity but Not High-Intensity Interval Training Improves Immune Function Biomarkers in Healthy Young Men
This study aimed to compare the effects of 2 training regimes; high-intensity interval training (HIIT) and moderate-intensity continuous training (MCT) performed at the same external load on hematological biomarkers in active young men. Sixteen men aged 18–20 years were randomly assigned to HIIT or MCT group. Aerobic capacity and hematological biomarkers were assessed before and after 9 weeks of interventions. At baseline, aerobic and hematological parameters were similar for the 2 groups. After intervention, no significant change was observed in maximal aerobic velocity and estimated VO2max in both groups. Leukocyte...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of Far-Infrared Emitting Ceramic Materials on Recovery During 2-Week Preseason of Elite Futsal Players
Nunes, RFH, Cidral-Filho, FJ, Flores, LJF, Nakamura, FY, Rodriguez, HFM, Bobinski, F, De Sousa, A, Petronilho, F, Danielski, LG, Martins, MM, Martins, DF, and Guglielmo, LGA. Effects of far-infrared emitting ceramic materials on recovery during 2-week preseason of elite futsal players. J Strength Cond Res 34(1): 235–248, 2020—We investigated the effects of far-infrared emitting ceramic materials (cFIR) during overnight sleep on neuromuscular, biochemical and perceptual markers in futsal players. Twenty athletes performed a 2-week preseason training program and during sleep wore bioceramic (BIO; n = 10) or place...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Methods of Monitoring Training Load and Their Association With Changes Across Fitness Measures in Hurling Players
Malone, S, Hughes, B, Collins, K, and Akubat, I. Methods of monitoring training load and their association with changes across fitness measures in hurling players. J Strength Cond Res 34(1): 225–234, 2020—The aim of the current investigation was to assess the dose-response relationship for various methods of monitoring training load (TL) and changes in aerobic and anaerobic fitness in hurling players. Training and match load measures were collected from 30 hurling players (speed at different blood lactate [vLT, vOBLA], maximal oxygen uptake [VO2max], speed at VO2max [vVO2max], peak treadmill velocity [PTV] runn...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Pacing Profiles and Competitive Performance of Elite Female 400-m Freestyle Swimmers
The objective of this study was to determine relationships between pacing parameters and competitive performance of elite female 400-m freestyle swimmers. Publicly available websites provided 50-m split and final times for 381 swims of 20 elite female swimmers in over 150 national and international competitions between 2004 and 2016. Most pacing profiles displayed negative quadratic curvature, with the fifth of the 8 laps being the median slowest. The mean times for the first and last laps were faster than predicted by the quadratic by 5.6 and 1.9%, respectively, and lap-to-lap variability was 0.65%. Scatter plots of each ...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Physical Characteristics of Youth Elite Golfers and Their Relationship With Driver Clubhead Speed
This study demonstrated relationships between CHS and body mass and upper-, lower-, and full-body concentric dominant power exercises. This study could aid in the development of training interventions for youth golfers. (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Multiple Repeated-Sprint Ability Test With Four Changes of Direction for Badminton Players (Part 2): Predicting Skill Level With Anthropometry, Strength, Shuttlecock, and Displacement Velocity
Phomsoupha, M and Laffaye, G. Multiple repeated-sprint ability test with four changes of direction for badminton players (part 2): predicting skill level with anthropometry, strength, shuttlecock, and displacement velocity. J Strength Cond Res 34(1): 203–211, 2020—The goal of this study was: (a) to assess general and specific lower and upper limb force, shuttlecock velocity, displacement ability, and the anthropometric characteristics of badminton players at 5 skill levels, and (b) to predict individual players' number of points. We divided 83 participants into groups of novice (n = 15), intermediate (n = 16), ...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Impact of Physical Performance and Anthropometric Characteristics on Serve Velocity in Elite Junior Tennis Players
This study aimed to investigate the impact of physical performance components and anthropometric characteristics on serve velocity (SV) in elite junior tennis players depending on the sex and age group. A sample of the best 1,019 (male = 625, female = 394) junior squad tennis players of the German Tennis Federation participated in the study involving complex anthropometric measurements (body height, body mass, sitting height, and arm span) and physical tests (e.g., SV, medicine ball throws [MBTs], hand grip strength, push-ups, back extension, countermovement jumps [CMJs], horizontal jumps, 20-m sprint, and tennis-specific ...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Evaluation of Strength and Conditioning Measures With Game Success in Division I Collegiate Volleyball: A Retrospective Study
Bunn, JA, Ryan, GA, Button, GR, and, and Zhang, S. Evaluation of strength and conditioning measures with game success in Division I collegiate volleyball: A retrospective study. J Strength Cond Res 34(1): 183–191, 2020—The purpose of this study was to retrospectively assess relationships between strength and conditioning (SC) measures and game performance in Division I volleyball. Five years of SC and game data were collected from 1 women's Division I collegiate team, n = 76. Strength and conditioning measures included T-drill, 18.3 m sprint, back squat, hang clean, vertical jump, and broad jump. All game and S...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Match Activities in Basketball Games: Comparison Between Different Competitive Levels
This study examined the (a) differences in the activity demands of official basketball games between different competitive levels (from elite to amateur levels) among a large cohort of adult male players and (b) match-to-match variations of basketball physical demands. Video-based time-motion analysis (TMA) was performed to assess the players' physical activity among 136 players. Match-to-match variations were determined analyzing 2 consecutive matches of the same level on 35 players. The frequency of occurrence (n per minutes) and the duration in percentage of playing time were calculated for high-intensity activity (HIA)...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Prioritizing Physical Determinants of International Elite Pole Vaulting Performance
This study investigated the relationships between pole vault height, approach speed, sprint-speed potential, and indicators of both explosive and reactive strength in 20 international female pole vaulters. Furthermore, changes in step characteristics between flying sprints and approach runs were analyzed. Data were collected during and after an international pole vault competition. The correlations between approach speed and vault height, between sprint speed and approach speed, and between explosive strength indicators and sprint speed were large or very large. However, the correlation between reactive strength and sprint...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Original Research Source Type: research