Examination of a Multi-ingredient Preworkout Supplement on Total Volume of Resistance Exercise and Subsequent Strength and Power Performance
This study examined the acute effects of a multi-ingredient preworkout supplement on (a) total-, lower-, and upper-body volume of resistance exercise and (b) the subsequent lower-body strength (isokinetic leg extension and flexion), lower-body power (vertical jump [VJ] height), upper-body power (bench throw velocity [BTv]), and cycle ergometry performance (critical power and anaerobic work capacity). Twelve men completed baseline strength and power measures before 2 experimental visits, supplement (SUP) and placebo (PL). The experimental visits involved a fatiguing cycling protocol 30 minutes after ingestion of the SUP or ...
Source: Journal of Strength and Conditioning Research - May 23, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Anthropometric and Physiological Characteristics of Brazilian Jiu-Jitsu Athletes: Erratum
No abstract available (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Erratum Source Type: research

Gender- and Muscle-Specific Responses During Fatiguing Exercise
Hill, EC, Housh, TJ, Smith, CM, Schmidt, RJ, and Johnson, GO. Gender- and muscle-specific responses during fatiguing exercise. J Strength Cond Res 32(5): 1471–1478, 2018—The purpose of the present investigation was to examine potential gender-related differences in electromyographic (EMG) and mechanomyographic (MMG) responses during submaximal, concentric, isokinetic, forearm flexion muscle contractions. Twelve men and 12 women performed concentric peak torque trials before (pretest) and after (posttest) a fatiguing exercise bout that consisted of 50 submaximal (65% of concentric peak torque), concentric, isoki...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Effect of Resistance Training on Blood Pressure and Autonomic Responses in Treated Hypertensives
This study evaluated the effect of resistance training (RT) on heart rate variability (HRV) and on blood pressure (BP) responses to acute and short-term exposure in treated hypertensive (HT) subjects. Twenty-one men participated in the study, 8 HT under drug treatment regimen and achieving adequate BP control before inclusion and 13 normotensive (NT). The RT protocol consisted of 12 sessions with eight exercises (leg extension, leg press, leg curl, bench press, seated row, triceps push-down, seated calf flexion, and seated arm curl) performed for two sets of 15–20 repetitions with 50% of one repetition maximum with 2...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Five-Kilometer Time Trial Reliability of a Nonmotorized Treadmill and Comparison of Physiological and Perceptual Responses vs. a Motorized Treadmill
This study examined the reliability of running performance across 3 nonmotorized treadmill (NMT) 5-km time trials (TTs) and physiological, gait, and perceptual differences at a 5-km pace for both NMT and motorized treadmills (MTs). Ten male runners experienced in road racing who had never run on an NMT completed 3 TT to establish personal best 5-km pace. In a later session, participants ran at this pace for 5 minutes on the NMT while metabolic, gait, and perceptual measures were recorded and then ran at outdoor 5-km personal best pace on an MT at 1% grade (counter-balanced crossover design). Intraclass correlation (ICC = 0...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Seasonal Variations of Bone Metabolism and Bone Mineral Density in Collegiate Alpine Skiers
This study investigated the seasonal variations in bone metabolism, mineral density, and physical characteristics in collegiate alpine skiers. Twelve male subjects (20.6 ± 1.5 years) were evaluated for body composition, bone mineral density (BMD), serum levels of osteocalcin (OC), bone alkaline phosphatase (BAP), tartrate-resistant acid phosphatase 5b (TRACP-5b), parathormone, and 25-hydroxy vitamin D. We also measured the knee extensor and flexor strength, maximal power, and vertical jump. Measurements were conducted in the preseason period (T1), competitive period (T2), end-of-season period (T3), and resting perio...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

A Comparison of Load-Velocity and Load-Power Relationships Between Well-Trained Young and Middle-Aged Males During Three Popular Resistance Exercises
This study examined the load-velocity and load-power relationships among 20 young (age 21.0 ± 1.6 years) and 20 middle-aged (age 42.6 ± 6.7 years) resistance-trained males. Participants performed 3 repetitions of bench press, squat, and bent-over-row across a range of loads corresponding to 20–80% of 1 repetition maximum (1RM). Analysis revealed effects (p (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Effect of Short-term Coenzyme Q10 Supplementation and Precooling on Serum Endogenous Antioxidant Enzymes of Elite Swimmers
This study aimed to investigate the effect of the use of a 2-week precooling strategy and supplementation coenzyme Q10 (CoQ10) on superoxide dismutase (SOD), catalase (CAT), and serum glutathione peroxidase (GPx) in elite, adolescent swimmers during heavy and regular trainings and recording of freestyle swimming. Thirty-six healthy males (mean ± SD; age: 17.5 ± 1.1 years, body fat content: 14.55 ± 1.75%) were randomly selected and divided into 4 groups of CoQ10 (300 mg·d−1), precooling (immersion in the water at 18 ± 0.5° C), supplementation with precooling, and control, each wi...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of Two Combined Exercise Designs Associated With High-Fat Meal Consumption on Postprandial Lipemia, Insulinemia, and Oxidative Stress
Farinha, JB, Macedo, CEO, Rodrigues-Krause, J, Krüger, RL, Boeno, FP, Macedo, RCO, Queiroz, JN, Teixeira, BC, and Reischak-Oliveira, A. Effects of two combined exercise designs associated with high-fat meal consumption on postprandial lipemia, insulinemia, and oxidative stress. J Strength Cond Res 32(5): 1422–1430, 2018—Impaired postprandial lipemia (PPL) response after the consumption of a high-fat meal (HFM) is linked to diabetes, oxidative stress, and cardiovascular events. The aim of this study was to investigate lipid and glucose metabolism and oxidative stress responses of 2 different combined exerci...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Equity of Physical Characteristics Between Adolescent Males and Females Participating in Single- or Mixed-Sex Sport
Krause, LM, Naughton, GA, Benson, AC, and Tibbert, S. Equity of physical characteristics between adolescent males and females participating in single- or mixed-sex sport. J Strength Cond Res 32(5): 1415–1421, 2018—Policies on single- or mixed-sex junior sports participation continue to be challenged publically and legally. Often challenges relate to perceptions of size and performance variability between adolescent males and females, yet the evidence base behind these challenges lacks recent review and rigor. Physical performance was compared between males and females from 2 groups of younger ( (Source: Journal...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Analysis of the Effect Size of Overweight in Muscular Strength Tests Among Adolescents: Reference Values According to Sex, Age, and Body Mass Index
Martínez-López, EJ, De La Torre-Cruz, M, Suárez-Manzano, S, and Ruiz-Ariza, A. Analysis of the effect size of overweight in muscular strength tests among adolescents: reference values according to sex, age, and body mass index. J Strength Cond Res 32(5): 1404–1414, 2018—The aim of this paper is to quantify the effect size of overweight on the results of muscular strength tests in adolescents and to report percentile tables based on sex, age, and body mass index (BMI). The study hypothesized that the effect size obtained from the difference between normal-weight and overweight youth would be...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Aerobic Exercise Preconception and During Pregnancy Enhances Oxidative Capacity in the Hindlimb Muscles of Mice Offspring
Liu, J, Lee, I, Feng, H-Z, Galen, SS, Hüttemann, PP, Perkins, GA, Jin, J-P, Hüttemann, M, and Malek, MH. Aerobic exercise preconception and during pregnancy enhances oxidative capacity in the hindlimb muscles of mice offspring. J Strength Cond Res 32(5): 1391–1403, 2018—Little is known about the effect of maternal exercise on offspring skeletal muscle health. The purpose of this study, therefore, was to determine whether maternal exercise (preconception and during pregnancy) alters offspring skeletal muscle capillarity and mitochondrial biogenesis. We hypothesized that offspring from exercised dams wo...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Warm-Up Exercises May Not Be So Important for Enhancing Submaximal Running Performance
Takizawa, K, Yamaguchi, T, and Shibata, K. Warm-up exercises may not be so important for enhancing submaximal running performance. J Strength Cond Res 32(5): 1383–1390, 2018—The purpose of this study was to determine an appropriate warm-up intensity for enhancing performance in submaximal running at 90% vV[Combining Dot Above]O2max (it assumes 3,000–5,000 m in track events). Seven trained male university athletes took part in this study (age: 21.3 ± 2.1 years, height: 169.3 ± 4.7 cm, body mass: 58.4 ± 5.6 kg, V[Combining Dot Above]O2max: 73.33 ± 5.46 ml·kg−1·...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Aerobic Exercise Supplemented With Muscular Endurance Training Improves Onset of Blood Lactate Accumulation
Farrell III, JW, Lantis, DJ, Ade, CJ, Cantrell, GS, and Larson, RD. Aerobic exercise supplemented with muscular endurance training improves onset of blood lactate accumulation. J Strength Cond Res 32(5): 1376–1382, 2018—Studies have shown that when aerobic exercise is supplemented with muscular endurance training metabolic adaptions occur that result in the delay of the onset of blood lactate accumulation (OBLA). However, previous studies have not explored any submaximal cardiorespiratory adaptations that may result from this training protocol. The aim of the current investigation was to evaluate the effect of ...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Short-Term Heat Acclimation and Precooling, Independently and Combined, Improve 5-km Time Trial Performance in the Heat
This study investigated the effect of short-term HA (STHA) combined with mixed methods PC, on endurance running performance and directly compared PC and HA. Nine amateur trained runners completed 5-km treadmill time trials (TTs) in the heat (32° C, 60% relative humidity) under 4 conditions; no intervention (CON), PC, short-term HA (5 days—HA) and STHA with PC (HA + PC). Mean (±SD) performance times were; CON 1,476 (173) seconds, PC 1,421 (146) seconds, HA 1,378 (116) seconds and HA + PC 1,373 (121) seconds. This equated to the following improvements versus CON; PC −3.7%, HA −6.6% and HA + PC &m...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Monitoring Resistance Exercise Intensity Using Ratings of Perceived Exertion in Previously Untrained Patients With Prostate Cancer Undergoing Androgen Deprivation Therapy
Fairman, CM, LaFountain, RL, Lucas, AR, and Focht, BC. Monitoring resistance exercise intensity using ratings of perceived exertion (RPE) in previously untrained patients with prostate cancer undergoing androgen deprivation therapy. J Strength Cond Res 32(5): 1360–1365, 2018—Exercise has been shown to be safe and effective for patients with prostate cancer (PrCa). The monitoring of resistance exercise (RE) intensity is an emerging area of interest in RE prescription. Rating of perceived exertion (RPE) is one of the most commonly used methods but has not yet been validated in this population. Thus, the purpose o...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Estimation of Repetitions to Failure for Monitoring Resistance Exercise Intensity: Building a Case for Application
Hackett, DA, Cobley, SP, and Halaki, M. Estimation of repetitions to failure for monitoring resistance exercise intensity: Building a case for application. J Strength Cond Res 32(5): 1352–1359, 2018—The purpose of this study was to (a) examine the accuracy of Estimated Repetitions to Failure (ERF) during resistance exercise between 2 sessions and (b) compare ERF to rating of perceived exertion (RPE) for determining proximity to momentary failure. Forty-eight adults with recreational resistance training experience performed 3 sets of 10 repetitions at 70% one-repetition maximum (1RM) and 80% 1RM for the chest pr...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Decrements in Neuromuscular Performance and Increases in Creatine Kinase Impact Training Outputs in Elite Soccer Players
Malone, S, Mendes, B, Hughes, B, Roe, M, Devenney, S, Collins, K, and Owen, A. Decrements in neuromuscular performance and increases in creatine kinase impact training outputs in elite soccer players. J Strength Cond Res 32(5): 1342–1351, 2018—The aim of the current investigation was to understand the impact of pretraining neuromuscular performance and creatine kinase (CK) status on subsequent training performance in elite soccer players. Thirty soccer players (age: 25.3 ± 3.1 years; height: 183 ± 7 cm; mass: 72 ± 7 kg) were involved in this observational study. Each morning before training...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Modulation of Isometric Quadriceps Strength in Soccer Players With Transcranial Direct Current Stimulation: A Crossover Study
Vargas, VZ, Baptista, AF, Pereira, GOC, Pochini, AC, Ejnisman, B, Santos, MB, João, SMA, and Hazime, FA. Modulation of isometric quadriceps strength in soccer players with transcranial direct current stimulation: a crossover study. J Strength Cond Res 32(5): 1336–1341, 2018—The aim of this study was to evaluate the effect of transcranial direct current stimulation (tDCS) on the maximum isometric muscle contraction (MVIC) of the knee extensors in soccer players at the preprofessional level. Twenty female soccer players aged 15–17 years (mean = 16.1; SD = 0.9) with 5.2 ± 2.6 years of training ...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Competition Load Described by Objective and Subjective Methods During a Surfing Championship
Fernández-Gamboa, I, Yanci, J, Granados, C, Freemyer, B, and Cámara, J. Competition load described by objective and subjective methods during a surfing championship. J Strength Cond Res 32(5): 1329–1335, 2018—The aims of this study were to describe the competition load of surfers during a single heat through objective and subjective methods and to analyze the relationship between objective and subjective methods with the judges' score. Ten competitive surfers were fitted with a global positioning system (GPS) during a competitive heat. The GPS was synchronized with a chronometer and a stationary v...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

The Relationship Between the Push Off Ground Reaction Force and Ball Speed in High School Baseball Pitchers
Oyama, S and Myers, JB. The relationship between the push off ground reaction force and ball speed in high school baseball pitchers. J Strength Cond Res 32(5): 1324–1328, 2018—Baseball pitching is a sequential movement that requires transfer of momentum from the lower extremity to the throwing arm. Therefore, the ground reaction force (GRF) during push off is suggested to play a role in production of ball speed. The purpose of this study was to investigate the correlation between GRF characteristics during push off and ball speed in high school baseball pitchers. A total of 52 pitchers performed fast pitches fr...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Organized Chaos in Late Specialization Team Sports: Weekly Training Loads of Elite Adolescent Rugby Union Players
Phibbs, PJ, Jones, B, Roe, G, Read, DB, Darrall-Jones, J, Weakley, J, Rock, A, and Till, K. Organized chaos in late specialization team sports: weekly training loads of elite adolescent rugby union players. J Strength Cond Res 32(5): 1316–1323, 2018—The aim of this study was to quantify the mean weekly training load (TL) of elite adolescent rugby union players participating in multiple teams and examine the differences between playing positions. Twenty elite male adolescent rugby union players (17.4 ± 0.7 years) were recruited from a regional academy and categorized by playing position: forwards (n = 10)...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

ACTN3 Genotype in Professional Sport Climbers
Ginszt, M, Michalak-Wojnowska, M, Gawda, P, Wojcierowska-Litwin, M, Korszeń-Pilecka, I, Kusztelak, M, Muda, R, Filip, AA, and Majcher, P. ACTN3 genotype in professional sport climbers. J Strength Cond Res 32(5): 1311–1315, 2018—The functional RR genotype of the alpha-actinin-3 (ACTN3) gene has been reported to be associated with elite sprint/power athlete status. Although large and rapidly increasing number of studies have investigated the associations between the ACTN3 genotypes and athletic performance in various sport disciplines, there is a lack of studies on the genetic predisposition in sport climbing, w...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Analysis of High-Intensity Skating in Top-Class Ice Hockey Match-Play in Relation to Training Status and Muscle Damage
In conclusion, ice hockey is a multiple-sprint sport that provokes fatigue in the latter half of a game. Forwards perform more intense skating than defensemen. Moreover, high-intensity game activities during top-class ice hockey are correlated with cardiovascular loading during a submaximal skating test. Taken together, training of elite ice-hockey players should improve the ability for repeated high-intensity skating, and testing should include the YYIR1-IHSUB test as an indicator for ice-hockey–specific physical match performance. (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Relationship Between Physiologic Tests, Body Composition Changes, and On-Ice Playing Time in Canadian Collegiate Hockey Players
Delisle-Houde, P, Chiarlitti, NA, Reid, RER, and Andersen, RE. Relationship between physiologic tests, body composition changes, and on-ice playing time in canadian collegiate hockey players. J Strength Cond Res 32(5): 1297–1302, 2018—Hockey player's body composition and physical fitness are suggested to influence coaching decisions regarding on-ice playing time. The purpose of this study was to explore the relationship between seasonal body composition changes, off-ice preseason testing, and on-ice metrics. Twenty-one Canadian collegiate hockey players (22.70 ± 1.30 years old, 181.0 ± 5.92 cm, 86...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Anthropometric and Athletic Performance Combine Test Results Among Positions Within Grade Levels of High School–Aged American Football Players
Leutzinger, TJ, Gillen, ZM, Miramonti, AM, McKay, BD, Mendez, AI, and Cramer, JT. Anthropometric and athletic performance combine test results among positions within grade levels of high school–aged American football players. J Strength Cond Res 32(5): 1288–1296, 2018—The purpose of this study was to investigate differences among player positions at 3 grade levels in elite, collegiate-prospective American football players. Participants' data (n = 7,160) were analyzed for this study (mean height [Ht] ± SD = 178 ± 7 cm, mass [Bm] = 86 ± 19 kg). Data were obtained from 12 different high ...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Noninvasive Assessment of Internal and External Player Load: Implications for Optimizing Athletic Performance
Heishman, AD, Curtis, MA, Saliba, E, Hornett, RJ, Malin, SK, and Weltman, AL. Noninvasive assessment of internal and external player load: implications for optimizing athletic performance. J Strength Cond Res 32(5): 1280–1287, 2018—Few data exist that assess athlete tracking and monitoring for the development of strategies to optimize performance and reduce fatigue in elite athletes. The purpose of the present study was to assess the efficacy of external load and internal stress monitoring as assessment tools for examining a performance index of fatigue. A retrospective analysis was performed on data collected ...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Mean Velocity vs. Mean Propulsive Velocity vs. Peak Velocity: Which Variable Determines Bench Press Relative Load With Higher Reliability?
This study aimed to compare between 3 velocity variables (mean velocity [MV], mean propulsive velocity [MPV], and peak velocity [PV]): (a) the linearity of the load-velocity relationship, (b) the accuracy of general regression equations to predict relative load (%1RM), and (c) the between-session reliability of the velocity attained at each percentage of the 1-repetition maximum (%1RM). The full load-velocity relationship of 30 men was evaluated by means of linear regression models in the concentric-only and eccentric-concentric bench press throw (BPT) variants performed with a Smith machine. The 2 sessions of each BPT var...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Effect of Different Training Methods on Stride Parameters in Speed Maintenance Phase of 100-m Sprint Running
In conclusion, although both training methods resulted in an increase in running time and RV, Com training method was more prominently effective method in improving RV, and this improvement was originated from the positive changes in SL during the speed maintaining phase. (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Four Weeks of Nordic Hamstring Exercise Reduce Muscle Injury Risk Factors in Young Adults
In conclusion, a short-term NHE training program (4 weeks; 8 training sessions) counteracts multiple hamstring injury risk factors in physically active young adults. (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Evaluation of Muscle Mechanical Capacities Through the Two-Load Method: Optimization of the Load Selection
Pérez-Castilla, A, Jaric, S, Feriche, B, Padial, P, and García-Ramos, A. Evaluation of muscle mechanical capacities through the 2-load method: Optimization of the load selection. J Strength Cond Res 32(5): 1245–1253, 2018—Recent research has revealed that the force-velocity relationship obtained from the “2-load method” (i.e., functional movements tested against just 2 external loads) could be a feasible method for the selective assessment of muscle force, velocity, and power-producing capacities. The study investigated the reliability and concurrent validity of the outcomes of the 2-l...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Different Patterns in Muscular Strength and Hypertrophy Adaptations in Untrained Individuals Undergoing Nonperiodized and Periodized Strength Regimens
In conclusion, our results demonstrated similar training-induced adaptations after 12 weeks of NP and periodized regimens. However, our findings suggest that in the latter half of the study (i.e., after the initial 6 weeks), the periodized regimens elicited greater rates of muscular adaptations compared with NP regimens. Strength coaches and practitioners should be aware that periodized regimens might be advantageous at latter stages of training even for untrained individuals. (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Compensatory Muscle Activation During Unstable Overhead Squat Using a Water-filled Training Tube
Glass, SC, and Albert, RW. Compensatory muscle activation during unstable overhead squat using a water-filled training tube. J Strength Cond Res 32(5): 1230–1237, 2018—The purpose of this study was to assess compensatory muscle activation of core and support muscle during an overhead squat using a water-filled training tube. Eleven experienced weightlifting (age = 20.10 ± 0.99, mass 89.17 ± 6.88 kg) men completed 3, 30-second trials of an overhead squat using an 11.4 kg tube that was partially filled with water. A central valve allowed 3 conditions of water movement: 50% open, 100% open, and a sta...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Kinetic Analysis of Horizontal Plyometric Exercise Intensity
This study also sought to assess sex differences in the intensity progression of these exercises. Ten men and 10 women served as subjects. The subjects performed a variety of plyometric exercises including the double-leg hop, standing long jump, single-leg standing long jump, bounding, skipping, power skipping, cone hops, and 45.72-cm hurdle hops. Subjects also performed the countermovement jump for comparison. All plyometric exercises were evaluated using a force platform. Dependent variables included the landing rate of force development and landing ground reaction forces for each exercise in the vertical, frontal, and s...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Sport-Specific Repeated Sprint Training Improves Punching Ability and Upper-Body Aerobic Power in Experienced Amateur Boxers
This study explored the effects of 4-week sport-specific sprint interval training on punch characteristics and endurance capacity in boxers. Experienced male amateur boxers (n = 18) participated in this 4-week training study and were divided into an experimental group (EG) and a control group (CG) (n = 9 per group). Both groups completed standard low-intensity training. The EG also completed 3 rounds (14 sets of 3-second all-out punching with a 10-second rest) of a simulated fight using a punching bag with a 1-minute rest between rounds 3 times per week, whereas the CG performed the same 3 rounds of a simulated fight at lo...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Training Volume, Not Frequency, Indicative of Maximal Strength Adaptations to Resistance Training
Colquhoun, RJ, Gai, CM, Aguilar, D, Bove, D, Dolan, J, Vargas, A, Couvillion, K, Jenkins, NDM, and Campbell, BI. Training volume, not frequency, indicative of maximal strength adaptations to resistance training. J Strength Cond Res 32(5): 1207–1213, 2018—To compare the effects of a high versus a moderate training frequency on maximal strength and body composition. Twenty-eight young, healthy resistance-trained men were randomly assigned to either: 3× per week (3×; n = 16) or 6× per week (6×; n = 12). Dependent variables (DVs) assessed at baseline and after the 6-week training interventio...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Acute Cardiometabolic Responses to a Novel Training Rope Protocol in Children
Faigenbaum, AD, Kang, J, Ratamess, NA, Farrell, A, Golda, S, Stranieri, A, Coe, J, and Bush, JA. Acute cardiometabolic responses to a novel training rope protocol in children. J Strength Cond Res 32(5): 1197–1206, 2018—The purpose of this study was to quantify the acute cardiometabolic responses to a novel training rope (TR) protocol in children. Fifteen boys (10.6 ± 1.4 years) were tested for peak oxygen uptake (V[Combining Dot Above]O2) on a treadmill and subsequently (2–7 days later) performed a progressive 10-minute protocol of 5 TR exercises (EX): EX1: standing side-to-side waves, EX2: seated ...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Tapering Practices of Strongman Athletes
This study provides the first empirical evidence of how strongman athletes taper for strongman competitions. Strongman athletes (n = 454) (mean ± SD: 33.2 ± 8.0 years, 178.1 ± 10.6 cm, 108.6 ± 27.9 kg, 12.6 ± 8.9 years general resistance training, 5.3 ± 5.0 years strongman implement training) completed a self-reported 4-page internet survey on tapering practices. Analysis by sex (male and female), age (≤30 and>30 years), body mass (≤105 and>105 kg), and competitive standard (local/regional amateur, national amateur and professional) was conducted. Eighty-seven percent (...
Source: Journal of Strength and Conditioning Research - April 25, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Authors’ Response
No abstract available (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - March 28, 2018 Category: Sports Medicine Tags: Manuscript Clarification Source Type: research

Effect of Compression Garments on Controlled Force Output After Heel-Rise Exercise
Kato, E, Nakamura, M, and Takahashi, H. Effect of compression garments on controlled force output after heel-rise exercise. J Strength Cond Res 32(4): 1174–1179, 2018—The purpose of this study was to elucidate the effects of compression garments (CG) on controlled force output after strenuous exercise. Sixteen healthy volunteers completed trials both with CG and without CG (control trial: CON) on 2 separate, random days which were at least 1 month apart. Both trials required participants to perform heel-rise exercises from maximal dorsiflexion to maximal plantar flexion 20 times with a single leg. The subjects ...
Source: Journal of Strength and Conditioning Research - March 28, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

The Relationship of Core Strength and Activation and Performance on Three Functional Movement Screens
In conclusion, performance on the 3 screens is predicted by core strength, even when accounting for “accessory” strength variables. Furthermore, it seems the screens elicit wide-ranging activation of core muscles. Although more investigation is needed, these screens, collectively, seem to be a good assessment of core strength. (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - March 28, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Phase Characteristics of the Countermovement Jump Force-Time Curve: A Comparison of Athletes by Jumping Ability
Sole, CJ, Mizuguchi, S, Sato, K, Moir, GL, and Stone, MH. Phase characteristics of the countermovement jump force-time curve: a comparison of athletes by jumping ability. J Strength Cond Res 32(4): 1155–1165, 2018—The purpose of this study was to compare the phase characteristics of the countermovement jump (CMJ) force-time (F-t) curve between athletes based on jumping ability. An initial sample of one-hundred fifty Division-I collegiate athletes were ranked based on CMJ height. Three performance groups were then formed by taking the top, middle, and lower 30 athletes (15 men and 15 women) from the sample. Phas...
Source: Journal of Strength and Conditioning Research - March 28, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Descriptive Profile of Lumbopelvic Control in Collegiate Baseball Pitchers
Laudner, K, Wong, R, Latal, J, and Meister, K. Descriptive profile of lumbopelvic control in collegiate baseball pitchers. J Strength Cond Res 32(4): 1150–1154, 2018—Throwing a baseball requires the transmission of forces generated in the lower extremity, through the trunk, then to the upper extremity, and ultimately out through the ball. Disruptions in this kinetic chain, specifically in lumbopelvic control, have been associated with decreased pitching performance and increased risk of injury. The purpose of this study was to establish normative data of lumbopelvic control among collegiate baseball pitchers. D...
Source: Journal of Strength and Conditioning Research - March 28, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Game Responses During Young Padel Match Play: Age and Sex Comparisons
García-Benítez, S, Courel-Ibáñez, J, Pérez-Bilbao, T, and Felipe, JL. Game responses during young padel match play: age and sex comparisons. J Strength Cond Res 32(4): 1144–1149, 2018—The purpose of this study was to assess match activity profile and temporal structure in U-16 and U-18 male and female padel players from the 2014 Spanish Youth National Championship. A total of 1,670 rallies from 12 matches were recorded through systematic observation. Variables pertaining to game and point duration, rest interval time, number of strokes per rally (SR), and match total duration ...
Source: Journal of Strength and Conditioning Research - March 28, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

An Evaluation of Time-Trial–Based Predictions of VO2max and Recommended Training Paces for Collegiate and Recreational Runners
Scudamore, EM, Barry, VW, and Coons, JM. An Evaluation of time-trial–based predictions of V[Combining Dot Above]O2max and recommended training paces for collegiate and recreational runners. J Strength Cond Res 32(4): 1137–1143, 2018—The purpose of the current study was to determine the accuracy of Jack Daniels' VDOT Running Calculator for the prediction of V[Combining Dot Above]O2max, and recommendations of interval and training paces (pIN and pTH) in samples of National Collegiate Athletic Association Division 1 track athletes (ATH, n = 11) and recreational runners (REC; n = 9). Predicted variable data w...
Source: Journal of Strength and Conditioning Research - March 28, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

The Age of Peak Marathon Performance in Cross-Country Skiing—The “Engadin Ski Marathon”
Knechtle, B and Nikolaidis, PT. The age of peak marathon performance in cross-country skiing—the “Engadin Ski Marathon.” J Strength Cond Res 32(4): 1131–1136, 2018—The age of the best endurance performance has been well investigated in flat city running marathons. However, we have no knowledge about the age of peak marathon performance in cross-country skiing, which would be of great practical value for athletes and coaches. Therefore, the aim of the present study was to examine the age of peak marathon performance in cross-country skiing. Participants were 162,991 men and 34,833 women competi...
Source: Journal of Strength and Conditioning Research - March 28, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Increased Leg Bone Mineral Density and Content During the Initial Years of College Sport
Scerpella, JJ, Buehring, B, Hetzel, SJ, and Heiderscheit, BC. Increased leg bone mineral density and content during the initial years of college sport. J Strength Cond Res 32(4): 1123–1130, 2018—Bone mineral density (BMD) and bone mineral content (BMC) data are useful parameters for evaluating how training practices promote bone health. We used dual-energy X-ray absorptiometry (DXA) to longitudinally assess sport-specific growth in leg and total body BMD/BMC over the initial 2 years of collegiate training. Eighty-five Division 1 collegiate basketball, hockey, and soccer athletes (50 males and 35 females; age 19...
Source: Journal of Strength and Conditioning Research - March 28, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Position-Specific Acceleration and Deceleration Profiles in Elite Youth and Senior Soccer Players
In conclusion, differences in the number and distribution of accelerations and decelerations appeared between player positions, which is of importance when monitoring training and match loads and when prescribing specific training exercises. Furthermore, youth players performed as much high-intensity activities as senior players, indicating that this is not a discriminating physiological parameter between these players. (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - March 28, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Relationship Between Skating Economy and Performance During a Repeated-Shift Test in Elite and Subelite Ice Hockey Players
Lamoureux, NR, Tomkinson, GR, Peterson, BJ, and Fitzgerald, JS. Relationship between skating economy and performance during a repeated-shift test in elite and subelite ice hockey players. J Strength Cond Res 32(4): 1109–1113, 2018—The purpose of this study was to determine the importance of skating economy to fatigue during repeated high-intensity efforts of a simulated ice hockey shift. Forty-five collegiate and Junior A male ice hockey players (aged 18–24 years) performed a continuous graded exercise test using a skate treadmill. Breath-by-breath data for oxygen consumption (V[Combining Dot Above]O2) an...
Source: Journal of Strength and Conditioning Research - March 28, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Effect of External Loading on Force and Power Production During Plyometric Push-ups
Hinshaw, TJ, Stephenson, ML, Sha, Z, and Dai, B. Effect of external loading on force and power production during plyometric push-ups. J Strength Cond Res 32(4): 1099–1108, 2018—One common exercise to train upper-body strength and power is the push-up. Training at the loads that would produce the greatest power is an effective way to increase peak power. The purpose of the current study was to quantify the changes in peak force, peak power, and peak velocity among a modified plyometric push-up and plyometric push-ups with or without external loading in physically active young adults. Eighteen male and 17 female ...
Source: Journal of Strength and Conditioning Research - March 28, 2018 Category: Sports Medicine Tags: Original Research Source Type: research