Short-Term Resistance Training Improves Cardiac Autonomic Modulation and Blood Pressure in Hypertensive Older Women: A Randomized Controlled Trial
Oliveira-Dantas, FF, Brasileiro-Santos, MdS, Thomas, SG, Silva, AS, Silva, DC, Browne, RAV, Farias-Junior, LF, Costa, EC, and Santos, AdC. Short-term resistance training improves cardiac autonomic modulation and blood pressure in hypertensive older women: a randomized controlled trial. J Strength Cond Res 34(1): 37–45, 2020—This randomized controlled trial investigated the efficacy of short-term resistance training (RT) on cardiac autonomic modulation and peripheral hemodynamic parameters in hypertensive older women. Twenty-five hypertensive older women who were insufficiently active (64.7 ± 4.7 years) p...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Can a Standardized Visual Assessment of Squatting Technique and Core Stability Predict Injury?
This study examined whether a standardized visual assessment of squatting technique and core stability can predict injury. Male adolescent and collegiate Gaelic players (n = 627) were assessed using the alternative core/trunk stability push-up test and a developed scoring system for the overhead squat and single-leg squat (SLS) that examined both overall impression and segmental criteria. A single summative score from the overall impression scores of all 3 tests was calculated. Sustained injuries were examined over a season. Results indicated that the single summative score did not predict those that sustained a lower-extr...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Kinematic Differences in Shoulder Roll and Hip Roll at Different Front Crawl Speeds in National Level Swimmers
This study aimed to quantify the range and velocity of hip roll, shoulder roll, and torso twist (produced by differences in the relative angle between shoulder roll and hip roll) in front crawl at different swimming speeds. Longitudinal torso kinematics was compared between sprint and 400-m pace front crawl using 3D kinematics of 13 elite Scottish front crawl specialists. The range (sprint: 78.1°; 400 m: 61.3°) and velocity of torso twist (sprint: 166.3°·s−1; 400 m: 96.9°·s−1) were greater at sprint than 400-m pace. These differences were attributed to reductions in hip roll (sprin...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of Personal Protective Equipment on the Performance of Federal Highway Policemen in Physical Fitness Tests
Marins, EF, Cabistany, L, Bartel, C, Dawes, J, and Del Vecchio, FB. Effects of personal protective equipment on the performance of Federal Highway Policemen in physical fitness tests. J Strength Cond Res 34(1): 11–19, 2020—Personal protective equipment (PPE), worn by police officers, provides protection and can modify physiological and performance responses during physical efforts. Physiological, perceptual, and physical responses were compared with PPE (WPPE) and without PPE (NPPE) among the Brazilian Federal Highway Policemen (FHP). Nineteen (n = 19) FHP completed 2 experimental trials: NPPE and WPPE (load = ...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Comparison of the Electromyographic Activity of the Trunk and Rectus Femoris Muscles During Traditional Crunch and Exercise Using the 5-Minute Shaper Device
This study aimed to compare the electromyographic (EMG) activity of the upper and lower rectus abdominis, external oblique abdominis, erector spinae, and rectus femoris (RF) muscles during traditional crunch and exercise using the 5-minute Shaper device. A convenience sample of 15 healthy men (mean ± SD; age: 23.65 ± 4.49 years, body fat percentage: 14.26 ± 3.56%) was selected. All men regularly participated in physical activity. Electromyographic data were collected for 5 repetitions of each abdominal exercise (traditional crunch and exercise using the 5-minute Shaper device at beginner, intermediate,...
Source: Journal of Strength and Conditioning Research - December 28, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Author's Response
No abstract available (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Manuscript Clarification Source Type: research

Manuscript Clarification for Ischemic Preconditioning Improves Strength Endurance Performance
No abstract available (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Manuscript Clarification Source Type: research

Polarized vs. Threshold Training Intensity Distribution on Endurance Sport Performance: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
The objective of this review was to systematically search the literature to identify and analyze data from randomized controlled trials that compare the effects of a polarized training model (POL) vs. a threshold training model (THR) on measurements of sport performance in endurance athletes. This systematic review and meta-analysis is registered with PROSPERO (CRD42016050942). The literature search was performed on November 6, 2016 and included SPORTDiscus (1800–present), CINAHL Complete (1981–present), and Medline with Full Text (1946–present). Studies were selected if they included: random allocation, ...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Brief Review Source Type: research

Movement Demands of Rugby Sevens in Men and Women: A Systematic Review and Meta-Analysis
Ball, S, Halaki, M, and Orr, R. Movement demands of rugby sevens in men and women: A systematic review and meta-analysis. J Strength Cond Res 33(12): 3475–3490, 2019—Global positioning systems (GPS) provide comprehensive information of player movement demands in rugby 7's. Although studies have investigated the use of GPS within many field-based team sports, the application of GPS within rugby 7's remains unclear. The aim of this review was to evaluate the movement demands and conduct a meta-analysis on comparable GPS measures to assess player movement in rugby 7's. A systematic search of electronic databases M...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Brief Review Source Type: research

Match Demands, Anthropometric Characteristics, and Physical Qualities of Female Rugby Sevens Athletes: A Systematic Review
Sella, FS, McMaster, DT, Beaven, CM, Gill, ND, and Hébert-Losier, K. Match demands, anthropometric characteristics, and physical qualities of female rugby sevens athletes: A systematic review. J Strength Cond Res 33(12): 3463–3474, 2019—Since the inclusion of rugby sevens in the 2016 Olympic Games, the popularity of women's rugby sevens has grown rapidly worldwide. This systematic review aimed to summarize the scientific literature addressing the match demands, anthropometric characteristics, and physical qualities of female rugby sevens athletes and to highlight differences between competition levels an...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Brief Review Source Type: research

A Systematic Review of Golf Warm-ups: Behaviors, Injury, and Performance
Ehlert, A and Wilson, PB. A systematic review of golf warm-ups: behaviors, injury, and performance. J Strength Cond Res 33(12): 3444–3462, 2019—Previous literature has demonstrated that warm-ups have the potential to increase physical performance and reduce risk of injury. Warm-ups before golf may have a similar result, but a systematic evaluation of their effects in golf is currently lacking. Three electronic databases (PubMed, SPORTDiscus, and Web of Science) were systematically searched to address 3 primary research questions: (a) What are the current warm-up behaviors of golfers?; (b) Is there an associatio...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Brief Review Source Type: research

Reliability of the OptoJump Next System for Measuring Temporal Values in Elite Racewalking
Hanley, B and Tucker, CB. Reliability of the OptoJump Next system for measuring temporal values in elite racewalking. J Strength Cond Res 33(12): 3438–3443, 2019—Racewalking is an Olympic event where athletes are not permitted a visible loss of contact, with the result that competitors try to minimize flight times. The accuracy of measurements taken during testing is dependent on valid and reliable systems to determine temporal values. The aim of the study was to compare different methodologies used to measure contact and flight times in overground and treadmill racewalking. Eighteen racewalkers completed overg...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Technical Report Source Type: research

Tracking of Time-Dependent Changes in Muscle Hardness After a Full Marathon
Inami, T, Nakagawa, K, Yonezu, T, Fukano, M, Higashihara, A, Iizuka, S, Abe, T, and Narita, T. Tracking of time-dependent changes in muscle hardness after a full marathon. J Strength Cond Res 33(12): 3431–3437, 2019—We sought to identify changes in individual muscle hardness after a full marathon and to track time-dependent changes using ultrasound strain elastography (SE). Twenty-one collegiate marathon runners were recruited. Muscle hardness (i.e., strain ratio, SR) was measured using SE for the rectus femoris (RF), vastus lateralis (VL), biceps femoris (BF) long head, tibialis anterior (TA), gastrocnemius me...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Research Note Source Type: research

Do Fast Older Runners Pace Differently From Fast Younger Runners in the “New York City Marathon”?
Nikolaidis, PT and Knechtle, B. Do fast older runners pace differently from fast younger runners in the “New York City Marathon”? J Strength Cond Res 33(12): 3423–3430, 2019—Although pacing strategies in the marathon and generally in endurance running have been well studied with regard to the effects of age group and performance level, little is known for their interaction. Thus, the aim of this was to examine whether fast runners of different age differ for pacing. Finishers (women, n = 117,595; men, n = 180,487) in the “New York City” Marathon between 2006 and 2016 were analyzed in 5-y...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Activity Profiles in U17, U20, and Senior Women's Brazilian National Soccer Teams During International Competitions: Are There Meaningful Differences?
Ramos, GP, Nakamura, FY, Penna, EM, Wilke, CF, Pereira, LA, Loturco, I, Capelli, L, Mahseredjian, F, Silami-Garcia, E, and Coimbra, CC. Activity profiles in U17, U20, and senior women's Brazilian national soccer teams during international competitions: are there meaningful differences? J Strength Cond Res 33(12): 3414–3422, 2019—The aim of this study was to compare locomotor activity profiles of Brazilian top-class female soccer players competing at distinct age brackets (under 17 [U17], under [U20], and senior). External match load of 14 U17, 14 U20, and 17 senior female soccer players competing in 6–7 f...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Relationship Between Repeated Sprint Ability, Aerobic Capacity, Intermittent Endurance, and Heart Rate Recovery in Youth Soccer Players
Rodríguez-Fernández, A, Sanchez-Sanchez, J, Ramirez-Campillo, R, Nakamura, FY, Rodríguez-Marroyo, JA, and Villa-Vicente, JG. Relationship between repeated sprint ability, aerobic capacity, intermittent endurance, and heart rate recovery in youth soccer players. J Strength Cond Res 33(12): 3406–3413, 2019—To investigate the relationship between repeated sprint ability (RSA) and several aerobic and anaerobic-related soccer-performance indicators, 45 youth soccer players (age 16.8 ± 0.1 years) were classified into “high” (HAF) or “low” aerobic fitness (LAF) (VO2m...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Ecological Validity and Reliability of an Age-Adapted Endurance Field Test in Young Male Soccer Players
Castagna, C, Krustrup, P, D'Ottavio, S, Pollastro, C, Bernardini, A, and Araújo Póvoas, SC. Ecological validity and reliability of an age-adapted endurance field test in young male soccer players. J Strength Cond Res 33(12): 3400–3405, 2019—The purpose of this study was to examine the reliability and the association with relevant match activities (ecological validity) of an age-adapted field test for intermittent high-intensity endurance known as Yo-Yo intermittent recovery level 1 children's test (YYIR1C) in young male soccer players. Twenty-eight young male outfield soccer players (age 11.1 &plu...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Training Load, Physical Performance, Biochemical Markers, and Psychological Stress During a Short Preparatory Period in Brazilian Elite Male Volleyball Players
In conclusion, a short PP in volleyball leads to increased TL, CK level, and psychological stress. Training load was related with the increase of CK, suggesting muscle damage without increased physical performance. (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Comparison of Static and Dynamic Balance at Different Levels of Sport Competition in Professional and Junior Elite Soccer Players
Jadczak, Ł, Grygorowicz, M, Dzudziński, W, and Śliwowski, R. Comparison of static and dynamic balance at different levels of sport competition in professional and junior elite soccer players. J Strength Cond Res 33(12): 3384–3391, 2019—The purpose of this study was to compare body balance control and balance recovery strategies of professional football players, representing various sports levels in static (eyes open, eyes closed) and dynamic conditions, both on the dominant and nondominant leg. Three groups of professional and junior elite soccer players were investigated: a PRO group (n = 52), a U-21 group ...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Deceleration, Acceleration, and Impacts Are Strong Contributors to Muscle Damage in Professional Australian Football
Gastin, PB, Hunkin, SL, Fahrner, B, and Robertson, S. Deceleration, acceleration, and impacts are strong contributors to muscle damage in professional Australian football. J Strength Cond Res 33(12): 3374–3383, 2019—The purpose of this study was to investigate the relationships between serum creatine kinase [CK], an indirect marker of muscle damage, and specific indices of match load in elite Australian football. Twenty-six professional players were assessed during a competitive Australian Football League (AFL) season. [CK] was collected 24–36 hours before match and 34–40 hours after match during 8 ...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Subjective Wellness, Acute: Chronic Workloads, and Injury Risk in College Football
In this study, one season of workload and wellness data from 42 collegiate football players were retrospectively analyzed. Daily 7:21 day exponentially weighted moving average (EWMA) ACWRs were calculated, and z-score fluctuations (“normal,” “better,” and “worse”) in sleep, soreness, energy, and overall wellness were assessed relative to the previous day ACWRs and considered as an interactive effect on the risk of noncontact injury within 0–3 days. Fifty-five noncontact injuries were observed, and injury risks were very likely higher when ACWRs were 2 SDs above (relative risk [RR]:...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Validity of Foot-To-Foot Bioelectrical Impedance for Estimating Body Composition in NCAA Division I Male Athletes: A 3-Compartment Model Comparison
Nickerson, BS, Snarr, RL, and Ryan, GA. Validity of foot-to-foot bioelectrical impedance for estimating body composition in NCAA Division I male athletes: A 3-compartment model comparison. J Strength Cond Res 33(12): 3361–3366, 2019—The purpose of this study was to validate single-frequency foot-to-foot bioelectrical impedance analysis (FF-BIA) against a 3-compartment (3C) model in NCAA Division I male athletes. Thirty-three athletes (football = 19, baseball = 8, basketball = 3, and cheerleading = 3) had body fat percentages (BF%) and fat-free mass (FFM) estimated using a 3C model and FF-BIA. The criterion 3C m...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Echo Intensity Reliability for the Analysis of Different Muscle Areas in Athletes
Lanferdini, FJ, Manganelli, BF, Lopez, P, Klein, KD, Cadore, EL, and Vaz, MA. Echo intensity reliability for the analysis of different muscle areas in athletes. J Strength Cond Res 33(12): 3353–3360, 2019—Skeletal muscles' echo intensity (EI) is used as a parameter to evaluate muscle damage and muscle quality after exercise or training. However, recent muscle EI studies have used regions of interest (ROIs) of different sizes for assessing muscle damage and muscle quality, which may lead to different results if the different ROIs from the same muscle are not reliable. Although a maximum rectangular ROI (RET-ROI)...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

A Single Dose of Oral ATP Supplementation Improves Performance and Physiological Response During Lower Body Resistance Exercise in Recreational Resistance-Trained Males
Freitas, MC, Cholewa, JM, Gerosa-Neto, J, Gonçalves, DC, Caperuto, EC, Lira, FS, and Rossi, FE. A single dose of oral ATP supplementation improves performance and physiological response during lower body resistance exercise in recreational resistance-trained males. J Strength Cond Res 33(12): 3345–3352, 2019—The aim of this study was to investigate the acute effect of adenosine-5'-triphosphate (ATP) supplementation on performance and physiological responses during resistance exercise in recreationally resistance-trained males. Eleven men (age = 27.5 ± 5.5 years, mass = 83.4 ± 9.8 kg, height...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of a Hip Flexor Stretching Program on Running Kinematics in Individuals With Limited Passive Hip Extension
Mettler, JH, Shapiro, R, and Pohl, MB. Effects of a hip flexor stretching program on running kinematics in individuals with limited passive hip extension. J Strength Cond Res 33(12): 3338–3344, 2019—Tightness of the hip flexor muscle group may theoretically contribute to altered kinematics of the lumbo-pelvic-hip (LPH) complex during dynamic movements. Therefore, the purpose of this study was to analyze the effects of a 3-week home-based stretching program on passive hip extension and sagittal plane kinematics of the LPH complex when running. Twenty healthy subjects with limited passive hip extension underwent ...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Ischemic Preconditioning Improves Strength Endurance Performance
Carvalho, L and Barroso, R. Ischemic preconditioning improves strength endurance performance. J Strength Cond Res 33(12): 3332–3337, 2019—Ischemic preconditioning (IPC) has been used to improve performances in aerobic and anaerobic activities. However, a few studies aimed at observing the effects of IPC on resistance training. The purpose of this study is to examine the effects of IPC on the number of repetitions performed during high-load resistance training. We also aimed at investigating blood lactate concentration and muscle activation in an attempt to understand the physiological mechanisms that may be cau...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Comparison of Lactate and Electromyographical Thresholds After an Exercise Bout
Snarr, RL, Esco, MR, Tolusso, DV, Hallmark, AV, Earley, RL, Higginbotham, JC, Fedewa, MV, and Bishop, P. Comparison of lactate and electromyographical thresholds after an exercise bout. J Strength Cond Res 33(12): 3322–3331, 2019—The electromyographical threshold (EMGT) has been previously validated as a means to predict the work rate at which lactate threshold (LT) occurs. The reliability of these measures has yet to be examined after a bout of exercise. The purpose was to determine the agreement between electromyography (EMG) and LT after a 30-minute bout of steady-state aerobic exercise. Participants complet...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of Short-Term In-Season Weightlifting Training on the Muscle Strength, Peak Power, Sprint Performance, and Ball-Throwing Velocity of Male Handball Players
This study analyzed the effects of in-season weightlifting training, conducted biweekly for 12 weeks. Twenty-two male handball players were divided into experimental (age: 20.3 ± 0.5 years, height: 1.85 ± 0.04 m, and body mass: 86.3 ± 9.4 kg) and control (age: 20.1 ± 0.5 years, height: 1.81 ± 0.05 m, and body mass: 83.9 ± 10.3 kg) groups, and performance was assessed before and after the intervention. Peak power was determined by a cycle ergometer force-velocity test, a vertical squat jump, and a countermovement jump. Measures of 1 repetition maximal strength included bench press, ...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Single-Leg Roman Chair Hold Is More Effective Than the Nordic Hamstring Curl in Improving Hamstring Strength-Endurance in Gaelic Footballers With Previous Hamstring Injury
This study investigated the effectiveness of the single-leg Roman hold and Nordic hamstring curl in improving hamstring strength-endurance. Twelve Gaelic footballers (mean ± SD age, height, and mass were 25.17 ± 3.46 years, 179.25 ± 5.88 cm, 85.75 ± 4.75 kg, respectively) with a history of hamstring injury were randomized into 2 groups that performed 6 weeks of either Nordic hamstring curl or single-leg Roman chair hold training. The single-leg hamstring bridge (SLHB) was measured before and after intervention. The Roman chair group showed a very likely moderate magnitude improvement on SLHB per...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Relative Age Effect in Collegiate Soccer: Influence of Nationality, Playing Position, and Class
Hurley, E, Comstock, BA, Haile, L, and Beyer, KS. Relative age effect in collegiate soccer: influence of nationality, playing position, and class. J Strength Cond Res 33(12): 3295–3301, 2019—The purpose of this study was to evaluate the existence of relative age effects (RAEs) in collegiate soccer. In addition, the impact of nationality, position, class, and National Collegiate Athletic Association (NCAA) tournament qualification status on the prevalence of RAEs was assessed. Birth dates from male NCAA Division I soccer athletes (n = 4,082) from the 2017/2018 season were categorized into quarters based on calen...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

A 28-Day Carbohydrate-Restricted Diet Improves Markers of Cardiometabolic Health and Performance in Professional Firefighters
Waldman, HS, Smith, JW, Lamberth, J, Fountain, BJ, and McAllister, MJ. A 28-day carbohydrate-restricted diet improves markers of cardiometabolic health and performance in professional firefighters. J Strength Cond Res 33(12): 3284–3294, 2019—We investigated the effects of a 4-week ad-libitum, nonketogenic, carbohydrate-restricted ( (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Absolute and Allometrically Scaled Lower-Limb Strength Differences Between Children With Overweight/Obesity and Typical Weight Children
Theis, N, Le Warne, M, Morrison, SC, Drechsler, W, and Mahaffey, R. Absolute and allometrically scaled lower-limb strength differences between children with overweight/obesity and typical weight children. J Strength Cond Res 33(12): 3276–3283, 2019—The purpose of this study was to compare isometric and isokinetic hip, knee, and ankle strength in children with overweight/obesity (OWB) and typical weight (TW) of age 6–12 years. Absolute torque and torque allometrically scaled to body mass and fat-free mass were derived to allow for comparison of strength irrespective of body size. Using a cross-sectional de...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Validity and Reliability of the Rear Foot Elevated Split Squat 5 Repetition Maximum to Determine Unilateral Leg Strength Symmetry
Helme, M, Bishop, C, Emmonds, S, and Low, C. Validity and reliability of the rear foot elevated split squat 5 repetition maximum to determine unilateral leg strength symmetry. J Strength Cond Res 33(12): 3269–3275, 2019—The purpose of this study was to examine the validity and reliability of the rear foot elevated split squat (RFESS) 5 repetition maximum (5RM) test as a field method for measuring unilateral leg strength symmetry. As a validated method of testing symmetry, the RFESS 5RM may be used by strength and conditioning coaches and sports medicine staff to measure the presence of imbalances with minimal e...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Effect of Work: Rest Ratio on Cycling Performance Following Sprint Interval Training: A Randomized Control Trial
Lloyd Jones, MC, Morris, MG, and Jakeman, JR. Effect of work: Rest ratio on cycling performance following sprint interval training: A randomized control trial. J Strength Cond Res 33(12): 3263–3268, 2019—Sprint interval training (SIT) has been shown to improve performance measures in a range of individuals, and it is understood that different responses can be elicited from different training protocols. However, consideration of changes in work to rest ratios could offer important insight into optimizing training programs. The purpose of this study was to investigate the effect of 3 different work to rest ratios...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Effect of Altering Body Posture and Barbell Position on the Within-Session Reliability and Magnitude of Force-Time Curve Characteristics in the Isometric Midthigh Pull
This study investigated the effect of altering body posture and barbell position on the reliability and magnitude of force-time characteristics generated during the IMTP. Seventeen strength-power athletes (n = 11 males, height: 177.5 ± 7.0 cm, body mass: 90.0 ± 14.1 kg, age: 30.6 ± 10.4 years; n = 6 females, height: 165.8 ± 11.4 cm; body mass: 66.4 ± 13.9 kg, age: 30.8 ± 8.7 years) with greater than 6 months of training experience in the clean (1 repetition maximum: 118.5 ± 20.6 kg, 77.5 ± 10.4 kg) volunteered to undertake the experimental protocol. Subjects performed...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Validity and Test-Retest Reliability of the 1080 Quantum System for Bench Press Exercise
This study assessed the validity and reliability of the 1080 Quantum (1080Q) during the bench press exercise. Twenty-seven resistance-trained men (28 ± 4 years; body mass 88.9 ± 12.8 kg; 1 repetition maximum [1RM] bench press 94.8 ± 10.7 kg) completed 2 test-retest sessions, separated by 1 week. In each session, subjects performed single repetitions at 30, 40, 50, 60, 70, and 80% of their bench press 1RM. Mean velocity (Vmean), peak velocity (Vpeak), mean force (Fmean), peak force (Fpeak), mean power (Pmean), and peak power (Ppeak) were simultaneously assessed using the 1080Q Synchro and a linear posit...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Comparison of Myoelectric Activity During a Suspension-Based and Traditional Split Squat
Miller, WM, Barnes, JT, Sofo, SS, and Wagganer, JD. Comparison of myoelectric activity during a suspension-based and traditional split squat. J Strength Cond Res 33(12): 3236–3241, 2019—Over several decades, traditional resistance training has incorporated body-mass suspension training (SPT), for example, Total-Body Resistance Exercise (TRX); however, very little research has been completed investigating the effects of lower body SPT. Therefore, the purpose of this study was to assess sex differences in myoelectric activity via electromyography while performing a stable (i.e., bench) traditional split squat (TS...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of Combined Resistance Training and Weightlifting on Motor Skill Performance of Adolescent Male Athletes
Pichardo, AW, Oliver, JL, Harrison, CB, Maulder, PS, Lloyd, RS, and Kandoi, R. Effects of combined resistance training and weightlifting on motor skill performance of adolescent male athletes. J Strength Cond Res 33(12): 3226–3235, 2019—Resistance training and weightlifting are regarded as safe and effective training methods for youth. However, no studies have examined the effects of a year-long resistance training program using weightlifting movements on strength, speed, or power. Therefore, the purpose of this study was to determine the long-term effects of combined resistance training (traditional strength t...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Retired Elite Athletes' Physical Activity, Physiological, and Psychosocial Outcomes During Single- and Double-Player Exergaming
McDonough, DJ, Pope, ZC, Zeng, N, Lee, JE, and Gao, Z. Retired elite athletes' physical activity, physiological, and psychosocial outcomes during single- and double-player exergaming. J Strength Cond Res 33(12): 3220–3225, 2019—Elite athletes (i.e., athletes who play sport professionally) are a population who commonly exceed recommended physical activity (PA) guidelines and have higher health statuses compared with the general population. However, elite athletes transitioning into retirement often become physically inactive given they no longer require long hours of training and competition, and their physiolog...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Kinematic Differences Between the Front and Back Squat and Conventional and Sumo Deadlift
fferences between the front and back squat and conventional and sumo deadlift. J Strength Cond Res 33(12): 3213–3219, 2019—The average concentric velocity (ACV) of a resistance exercise movement is inversely related to the load lifted. Previous work suggests that different resistance exercises differ in ACV at the same relative load. Currently, there is limited evidence to determine whether the style of exercise (e.g., front or back squat [BS]; sumo-style or conventional-style deadlift) also affects the load-velocity profile or other kinematic variables such as the peak concentric velocity (PCV) and linear disp...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Investigating “A Consensus of Uninformed Dogma”: C.H. McCloy and Strength Training Research at the University of Iowa in the Mid-Twentieth Century
Shurley, JP. Investigating “A Consensus of Uninformed Dogma”: C.H. McCloy and Strength Training Research at the University of Iowa in the Mid-Twentieth Century. J Strength Cond Res 33(12): 3201–3212, 2019—Into the 1960s, many coaches advised their athletes to avoid weight training, fearing that lifting weights would result in their becoming stiff, slow, and “muscle-bound.” By the early 1970s, however, some teams had begun hiring specialists to devise and supervise strength and conditioning programs for their athletes. This paradigm shift in the understanding of the relationship between s...
Source: Journal of Strength and Conditioning Research - November 26, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Physiological and Tactical On-court Demands of Water Polo
Botonis, PG, Toubekis, AG, and Platanou, TI. Physiological and tactical on-court demands of water polo. J Strength Cond Res 33(11): 3188–3199, 2019—The purpose of the present review is to provide a quantification of the specific game's activities performed by elite water polo players and a comprehensive overview of the physiological requirements reflecting physical and tactical on-court demands in water polo. Game analysis demonstrates that various swimming movements occur throughout a match play, although approximately 50% of these are recorded in horizontal body position. The various offensive and defensive t...
Source: Journal of Strength and Conditioning Research - October 23, 2019 Category: Sports Medicine Tags: Brief Review Source Type: research

Effects of Hip Abductor Muscles Exercises on Pain and Function in Patients With Patellofemoral Pain: A Systematic Review and Meta-Analysis
Rogan, S, Haehni, M, Luijckx, E, Dealer, J, Reuteler, S, and Taeymans, J. Effects of hip abductor muscles exercises on pain and function in patients with patellofemoral pain: A systematic review and meta-analysis. J Strength Cond Res 33(11): 3174–3187, 2019—This systematic review and meta-analysis considered the effects of hip strengthening (i.e., abductor and external rotator muscles) vs. no hip strengthening on pain and of hip strengthening combined with knee strengthening vs. knee strengthening (i.e., quadriceps muscles) alone on pain and functional status in patients with patellofemoral pain (PFP). Eleven, ...
Source: Journal of Strength and Conditioning Research - October 23, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Reliability, Usefulness, and Factorial Validity of Change-of-direction Speed Tests in Adolescent Basketball Players
Stojanović, E, Aksović, N, Stojiljković, N, Stanković, R, Scanlan, AT, and Milanović, Z. Reliability, usefulness, and factorial validity of change-of-direction speed tests in adolescent basketball players. J Strength Cond Res 33(11): 3162–3173, 2019—The purposes of this study were to (1) determine the reliability, usefulness, and factorial validity of change-of-direction speed (CODS) tests in adolescent basketball players and (2) evaluate positional differences in test performances. Elite, adolescent male basketball players (n = 53; 17.3 ± 1.0 years) completed 6 CODS tests: “Lane Arrow Closeou...
Source: Journal of Strength and Conditioning Research - October 23, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Efficacy of a Goal Setting and Implementation Planning Intervention on Firefighters' Cardiorespiratory Fitness
Bycura, DK, Dmitrieva, NO, Santos, AC, Waugh, KL, and Ritchey, KM. Efficacy of a Goal Setting and Implementation Planning Intervention on Firefighters' Cardiorespiratory Fitness. J Strength Cond Res 33(11): 3151–3161, 2019—The purpose of this study was to assess the effectiveness of a goal setting and implementation planning (GSIP) intervention on cardiorespiratory fitness among firefighters. Male career firefighters (N = 20) from a large municipal fire department were assigned to an intervention arm (n = 12) or passive control arm (n = 8) of a 14-week study involving cardiorespiratory exercise. The interventio...
Source: Journal of Strength and Conditioning Research - October 23, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Strength Testing After Anterior Cruciate Ligament Reconstruction: A Prospective Cohort Study Investigating Overlap of Tests
In conclusion, there is little room for omission of individual strength testing protocol components because of the lack of overlap between tests. Isometric, eccentric, and concentric tests may all provide unique information and all, therefore, should be considered for inclusion. (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - October 23, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Comparison of the Effects of Endurance Training on Alternate Days and on Consecutive 4 Days Each Week for 8 Weeks on the Abundance of PGC-1α, CaMKII, NRF-1, mtTFA, and COXIV Proteins in Rat Skeletal Muscle
Qiu, J, Huang, L, Davie, AJ, and Zhou, S. Comparison of the effects of endurance training on alternate days and on consecutive 4 days each week for 8 weeks on the abundance of PGC-1α, CaMKII, NRF-1, mtTFA, and COXIV proteins in rat skeletal muscle. J Strength Cond Res 33(11): 3136–3144, 2019—The aim of this study was to compare the effects of 2 training protocols, training on alternate days (A) or on consecutive 4 days followed by 3 days of rest in each week (C) for 8 weeks, on selected proteins involved in the biogenesis and function of mitochondria in skeletal muscle. Eighty male Sprague Dawley rats wer...
Source: Journal of Strength and Conditioning Research - October 23, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Upper Respiratory Tract Infection and Mucosal Immunity in Young Ice Hockey Players During the Pretournament Training Period
In conclusion, the tapering period positively affects the mucosal immune function, especially sIgA1 and sIgA2 concentrations, with no significant change in the frequency of URTI in young ice hockey players. (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - October 23, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Physiological and Sport-Specific Comparison Between Division I and Division II Italian Male Field Hockey Players
Bartolomei, S, Nigro, F, Gubellini, L, Ciacci, S, Merni, F, Treno, F, Cortesi, M, and Semprini, G. Physiological and sport-specific comparison between Division I and Division II Italian male field hockey players. J Strength Cond Res 33(11): 3123–3128, 2019—The purpose of this study was to compare the anthropometric and performance profiles of Division I (D1) and Division II (D2) Italian field hockey players. Fifteen DI players and 15 D2 players (age = 25.4 ± 5.2 years; body mass = 78.5 ± 9.0 kg; and body height = 179.6 ± 7.8 cm) were assessed on one occasion for anthropometry, body composit...
Source: Journal of Strength and Conditioning Research - October 23, 2019 Category: Sports Medicine Tags: Original Research Source Type: research

Changes in Player Activity Profiles After the 2015 FIH Rule Changes in Elite Women's Hockey
McMahon, GE and Kennedy, RA. Changes in player activity profiles after the 2015 FIH rule changes in elite women's hockey. J Strength Cond Res 33(11): 3114–3122, 2019—The aim of this study was to compare the player activity profiles of elite international women's hockey players before (2014) and after (2015) the 2015 the International Hockey Federation (FIH) match rule changes at team and positional levels. The match activity profiles (n = 400) of 19 female hockey players (age 23 ± 4 years, mass 63.6 ± 5.5 kg, VO2max 57 ± 6 ml·kg−1·min−1 in 2014, 58 ± 6 ml&mi...
Source: Journal of Strength and Conditioning Research - October 23, 2019 Category: Sports Medicine Tags: Original Research Source Type: research