Heart Rate Variability and Training Load Among National Collegiate Athletic Association Division 1 College Football Players Throughout Spring Camp
Flatt, AA, Esco, MR, Allen, JR, Robinson, JB, Earley, RL, Fedewa, MV, Bragg, A, Keith, CM, and Wingo, JE. Heart rate variability and training load among National Collegiate Athletic Association Division 1 college football players throughout spring camp. J Strength Cond Res 32(11): 3127–3134, 2018—The purpose of this study was to determine whether recovery of cardiac-autonomic activity to baseline occurs between consecutive-day training sessions among positional groups of a collegiate football team during Spring camp. A secondary aim was to evaluate relationships between chronic (i.e., 4-week) heart rate variabi...
Source: Journal of Strength and Conditioning Research - November 1, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Stature, Body Mass, and Body Mass Index in High School American Football Players: Appropriate Determinants of Obesity Prevalence?
Mendez, AI, Miramonti, AA, Gillen, ZM, McKay, BD, Leutzinger, TJ, and Cramer, JT. Stature, body mass, and BMI in high school american football players: Appropriate determinants of obesity prevalence? J Strength Cond Res 32(11): 3119–3126, 2018—The purpose of this study was to evaluate stature (HT), mass (BM), body mass index (BMI), and obesity prevalence based on BMI categories in a large sample (n = 7,175) of high school American football players enrolled as freshmen, sophomores, or juniors. Players were categorized by their positions: offensive linemen (OLs), defensive linemen (DLs), tight end, defensive end,...
Source: Journal of Strength and Conditioning Research - November 1, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Performance of Future Elite Players at the National Football League Scouting Combine
Hedlund, DP. Performance of future elite players at the NFL scouting combine. J Strength Cond Res 32(11): 3112–3118, 2018—The purpose of this study is to examine players' physical and performance measures taken at the National Football League (NFL) Scouting Combine and compare these with their future performance in the NFL. From 2002 to 2016, 3 types of player data (N = 5,506) were collected from secondary data sources. Results of players earned on various NFL Scouting Combine drills and measurements (e.g., height, body mass, 40-yard dash time, vertical jump, bench press repetitions, shuttle run time, and 3-con...
Source: Journal of Strength and Conditioning Research - November 1, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of a 15-Day Low Carbohydrate, High-Fat Diet in Resistance-Trained Men
This study examined the effects of a 15-day isocaloric low carbohydrate (50% E) (LCHF) diet on physiological and metabolic alterations in resistance-trained (RT) men. College-aged RT men (n = 11) completed 4 V[Combining Dot Above]O2max tests using treadmill every 5 days during the 15-day trial. Blood was drawn intravenously pre-exercise across each experimental trial for insulin, cortisol, and glucose. Pulmonary data were collected and substrate oxidation (OXI) was calculated during exercise. Body mass decreased (p (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - November 1, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Can Caffeine Intake Improve Neuromuscular and Technical-Tactical Performance During Judo Matches?
This study aimed to verify the effect of caffeine intake on blood lactate concentrations and neuromuscular and technical-tactical performance during simulated judo matches. Fourteen male judo athletes received capsules containing caffeine or placebo and were evaluated in both conditions. Before the baseline and 1 hour after the caffeine/placebo intake, athletes performed the countermovement jump (CMJ) test, handgrip strength, judogi grip strength test (JGST), and blood samples were collected. Subsequently, the athletes were submitted to three 5-minute matches with 15-minute intervals. All neuromuscular tests were performed...
Source: Journal of Strength and Conditioning Research - November 1, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Acute Effect of Citrulline Malate Supplementation on Upper-Body Resistance Exercise Performance in Recreationally Resistance-Trained Men
Gonzalez, AM, Spitz, RW, Ghigiarelli, JJ, Sell, KM, and Mangine, GT. Acute effect of citrulline malate supplementation on upper-body resistance exercise performance in recreationally resistance-trained men. J Strength Cond Res 32(11): 3088–3094, 2018—To investigate the effect of citrulline malate (CM) supplementation on upper-body resistance exercise performance, 12 recreationally resistance-trained men (21.4 ± 1.6 years; 163.0 ± 46.2 cm; 85.0 ± 12.4 kg) underwent 2 testing sessions administered in a randomized, double-blind fashion. During each visit, participants were provided either 8 g ...
Source: Journal of Strength and Conditioning Research - November 1, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Pacing Strategy of a Full Ironman Overall Female Winner on a Course With Major Elevation Changes
Pryor, JL, Adams, WM, Huggins, RA, Belval, LN, Pryor, RR, and Casa, DJ. Pacing strategy of a full Ironman overall female winner on a course with major elevation changes. J Strength Cond Res 32(11): 3080–3087, 2018—The purpose of this study was to use a mixed-methods design to describe the pacing strategy of the overall female winner of a 226.3-km Ironman triathlon. During the race, the triathlete wore a global positioning system and heart rate (HR)-enabled watch and rode a bike outfitted with a power and cadence meter. High-frequency (every km) analyses of mean values, mean absolute percent error (MAPE), and no...
Source: Journal of Strength and Conditioning Research - November 1, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Sex Differences in Mechanical Properties of the Achilles Tendon: Longitudinal Response to Repetitive Loading Exercise
Lepley, AS, Joseph, MF, Daigle, NR, Digiacomo, JE, Galer, J, Rock, E, Rosier, SB, and Sureja, PB. Sex differences in mechanical properties of the Achilles tendon: Longitudinal response to repetitive loading exercise. J Strength Cond Res 32(11): 3070–3079, 2018—Sex differences have been observed in the mechanical properties of the Achilles tendon, which may help to explain the increased risk of injury in men. However, the response and recovery of tendon mechanics to repetitive loading exercise, as well as sex-dependent responses, are not well understood. The purpose of our study was to compare Achilles tendon me...
Source: Journal of Strength and Conditioning Research - November 1, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Higher Quadriceps Roller Massage Forces Do Not Amplify Range-of-Motion Increases nor Impair Strength and Jump Performance
Grabow, L, Young, JD, Alcock, LR, Quigley, PJ, Byrne, JM, Granacher, U, Škarabot, J, and Behm, DG. Higher quadriceps roller massage forces do not amplify range-of-motion increases nor impair strength and jump performance. J Strength Cond Res 32(11): 3059–3069, 2018—Roller massage (RM) has been reported to increase range of motion (ROM) without subsequent performance decrements. However, the effects of different rolling forces have not been examined. The purpose of this study was to compare the effects of sham (RMsham), moderate (RMmod), and high (RMhigh) RM forces, calculated relative to the individuals'...
Source: Journal of Strength and Conditioning Research - November 1, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Comparison of Sprint Interval and Endurance Training in Team Sport Athletes
Kelly, DT, Tobin, C, Egan, B, Carren, AM, O'Connor, PL, McCaffrey, N, and Moyna, NM. Comparison of sprint interval and endurance training in team sport athletes. J Strength Cond Res 32(11): 3051–3058, 2018—High-volume endurance training (ET) has traditionally been used to improve aerobic capacity but is extremely time-consuming in contrast to low-volume short-duration sprint interval training (SIT) that improves maximal oxygen uptake (V[Combining Dot Above]O2max) to a similar extent. Few studies have compared the effects of SIT vs. ET using running-based protocols, or in team sport athletes. Club level male Gae...
Source: Journal of Strength and Conditioning Research - November 1, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of Plyometric and Resistance Training on Muscle Strength, Explosiveness, and Neuromuscular Function in Young Adolescent Soccer Players
In conclusion, 8-week free-weight resistance and plyometric training resulted in significant improvements in muscle strength and jump performance. Training resulted in similar muscle hypertrophy in the 2 training modes, with no clear differences in muscle performance. Plyometric training was more effective in improving jump performance, whereas free-weight RT was more advantageous in improving peak torque, where the stretch reflex was not involved. (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - November 1, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Characteristics of a National Level Female Weightlifter Peaking for Competition: A Case Study
This study investigated physiological and performance changes of a national-level 69 kg female weightlifter after 3 competition phases over a 28-week training period. The athlete first trained for a regional championship (weeks 1–12), followed by a local competition (weeks 13–23) and the national championship (weeks 24–28). Body mass, vastus lateralis cross-sectional area (CSA), and unloaded and loaded squat jump performance were assessed weekly during each 4-week competition phase. Serum biomarkers and dynamic midthigh pulls were assessed before and after each competition phase. Weightlifting performance...
Source: Journal of Strength and Conditioning Research - November 1, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Range of Motion Adaptations in Powerlifters
Gadomski, SJ, Ratamess, NA, and Cutrufello, PT. Range of motion adaptations in powerlifters. J Strength Cond Res 32(11): 3020–3028, 2018—The aim of this study was to investigate range of motion (ROM) and training patterns in powerlifters. Upper- and lower-extremity passive ROMs were assessed through goniometry in 15 male powerlifters (35.3 ± 13.7 years) and 15 age-matched controls (34.9 ± 14.6 years). The Apley scratch test and modified Thomas test were used to assess ROM across multiple joints. Training frequency, stretching frequency, and exercise selection were recorded using questionnaires. Pa...
Source: Journal of Strength and Conditioning Research - November 1, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Relationships Between Height, Arm Length, and Leg Length on the Mechanics of the Conventional and High-Handle Hexagonal Bar Deadlift
Lockie, RG, Moreno, MR, Orjalo, AJ, Lazar, A, Liu, TM, Stage, AA, Birmingham-Babauta, SA, Stokes, JJ, Giuliano, DV, Risso, FG, Davis, DL, and Callaghan, SJ. Relationships between height, arm length, and leg length on the mechanics of the conventional and high-handle hexagonal bar deadlift. J Strength Cond Res 32(11): 3011–3019, 2018—The study investigated relationships between arm length (AL) and leg length (LL) and conventional deadlift (CD) and high-handle hexagonal bar deadlift (HHBD) mechanics. Twenty-three resistance-trained subjects (14 men and 9 women) completed a 1 repetition maximum CD and HHBD. A line...
Source: Journal of Strength and Conditioning Research - November 1, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Divergent Blood Pressure Response After High-Intensity Interval Exercise: A Signal of Delayed Recovery?
The objective of this commentary is to highlight potential factors influential to the adaptation of high-intensity exercise. Herein, we present a rationale supporting the contention that elevated systolic blood pressure, after a bout of high-intensity exercise, may be indicative of delayed/incomplete recovery. Relative to type I skeletal muscle fibers, the unique cellular/vascular characteristics of type II muscle fibers may necessitate longer recovery periods, especially when exposed to repeated high-intensity efforts (i.e., intervals). In addition to the noted race disparities in cardiometabolic disease risk, including h...
Source: Journal of Strength and Conditioning Research - November 1, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

In Memoriam: Dr. Terry Todd (1938–2018) Pioneering Powerlifter, Writer, Sport Promoter, and Historian Who Changed the Cultural Paradigm for Strength
No abstract available (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - November 1, 2018 Category: Sports Medicine Tags: Memoriam Source Type: research

Relationship Between Change of Direction, Speed, and Power in Male and Female National Olympic Team Handball Athletes
Pereira, LA, Nimphius, S, Kobal, R, Kitamura, K, Turisco, LAL, Orsi, RC, Cal Abad, CC, and Loturco, I. Relationship between change of direction, speed, and power in male and female National Olympic Team handball athletes. J Strength Cond Res 32(10): 2987–2994, 2018—The aims of this study were to (a) assess the relationship between selected speed- and power-related abilities (determined by 20-m sprint, unloaded countermovement jump [CMJ] and squat jump [SJ], and loaded jump squat [JS]) and performance in 2 distinct change of direction (COD) protocols (Zigzag test and T-test) and (b) determine the magnitude of di...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Research Note Source Type: research

Influence of Muscle Quality on the Differences in Strength From Slow to Fast Velocities in Career Firefighters
Gerstner, GR, Giuliani, HK, Mota, JA, and Ryan, ED. Influence of muscle quality on the differences in strength from slow to fast velocities in career firefighters. J Strength Cond Res 32(10): 2982–2986, 2018—The purpose of this study was to examine the relationship between ultrasound-derived muscle quality and the %decrease in peak torque (PT) from slow to fast velocities in career firefighters. Thirty-nine male career firefighters (mean ± SD: age = 36.90 ± 6.87 years; stature = 180.93 ± 6.98 cm; mass = 109.30 ± 20.57 kg; and body mass index [BMI] = 33.24 ± 4.95 kg·m&mi...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Research Note Source Type: research

Effect of High-Dose, Short-Duration β-Alanine Supplementation on Circulating IL-10 Concentrations During Intense Military Training
This study examined the effect of β-alanine as a potential anti-inflammatory agent during intense military training. Twenty soldiers (20.1 ± 0.6 years) from an elite combat unit were randomly assigned to either a β-Alanine (BA) or placebo (PL) group. Soldiers were provided with 12 g·d−1 of either BA or PL for 7 days between 2 intensive periods of navigational training and restricted sleep. During the initial training period, soldiers navigated on average 27.8 km·d−1 with ∼50% of their body mass in their packs for 5 days. Soldiers returned to base and began a 7-day supplementat...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Research Note Source Type: research

Acute Hypotension After Moderate-Intensity Handgrip Exercise in Hypertensive Elderly People
Souza, LR, Vicente, JB, Melo, GR, Moraes, VC, Olher, RR, Sousa, IC, Peruchi, LH, Neves, RV, Rosa, TS, Ferreira, AP, and Moraes, MR. Acute hypotension after moderate-intensity handgrip exercise in hypertensive elderly people. J Strength Cond Res 32(10): 2971–2977, 2018—Isometric handgrip (IHG) training is effective in reducing blood pressure (BP), but little is known about the occurrence of acute hypotension by postisometric exercise hypotension (PIEH) and the underlying mechanisms. Ten sedentary hypertensive elderly people (7 women and 3 men) individuals, with a mean age of 73.2 ± 2.2 years and systolic ...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Influence of Acute Concurrent Exercise Performed in Public Fitness Facilities on Ambulatory Blood Pressure Among Older Adults in Rio de Janeiro City
Cordeiro, R, Monteiro, W, Cunha, F, Pescatello, LS, and Farinatti, P. Influence of acute concurrent exercise performed in public fitness facilities on ambulatory blood pressure among older adults in Rio de Janeiro city. J Strength Cond Res 32(10): 2962–2970, 2018—The project “Third-Age Academies’” (TAAs) is a public policy providing supervised physical activities to over 40,000 seniors at open-access facilities (squares etc.) in Rio de Janeiro, Brazil. We investigated whether TAA concurrent exercise circuit induced postexercise hypotension (PEH) in individuals older than 60 years. Blood pressu...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Physiological and Biomechanical Responses to an Acute Bout of High Kicking in Dancers
Rice, PE, Gurchiek, RD, and McBride, JM. Physiological and biomechanical responses to an acute bout of high kicking in dancers. J Strength Cond Res 32(10): 2954–2961, 2018—High-kick precision competitive dance involves the integration of kicking inline, jumping, and turning during a 3-minute routine and causes a disturbance to both aerobic and anaerobic systems. However, no known study has quantified the effect of a hick-kick–specific protocol on blood lactate (BL), heart rate (HR), and countermovement jump (CMJ) performance. A group of adolescent high-kick dancers (n = 20; age = 15.0 ± 1.8 years; ...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Physiological Responses to and Athlete and Coach Perceptions of Exertion During Small-Sided Basketball Games
This study describes heart rate (HR) responses during different small-sided games (SSGs) in junior basketball players and identifies the level of agreement between athlete and coach perceptions of internal training load calculated using the in-task rating of perceived exertion (RPE) method. Over a 6-week period, 12 male junior basketball players, who played in the Spanish national under-18 League, played 7 games of one-a-side (1v1), 6 games of 2-a-side (2v2), 8 games of 5-a-side (5v5), and 5 games of superiority (3v2) situations. During 1v1, 2v2, 5v5, and 3v2, peak HRs were 90.27 ± 3.37%, 92.68 ± 3.29%, 92.01...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Workloads of Competitive Surfing: Work-to-Relief Ratios, Surf-Break Demands, and Updated Analysis
Farley, ORL, Secomb, JL, Raymond, ER, Lundgren, LE, Ferrier, BK, Abbiss, CR, and Sheppard, JM. Workloads of competitive surfing: work-to-relief ratios, surf-break demands, and updated analysis. J Strength Cond Res 32(10): 2939–2948, 2018—The study provides an in-depth descriptive and quantitative time-motion analysis of competitive surfing, using Global Positioning System (GPS) units and video synchronization, which serves to extend upon the results of Farley, Harris, and Kilding (Journal of Strength and Conditioning Research, 26, 7 [2012]). In addition, comparisons between locations and surfers competing in th...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Frequency Speed of Kick Test Performance Comparison Between Female Taekwondo Athletes of Different Competitive Levels
Santos, JFS and Franchini, E. Frequency speed of kick test performance comparison between female taekwondo athletes of different competitive levels. J Strength Cond Res 32(10): 2934–2938, 2018—Construct validity is a desirable characteristic in any performance test to differentiate athletes. However, no taekwondo-specific test was investigated with this purpose. The purpose of this study was to compare female taekwondo athletes grouped in different competitive levels. Forty-two female taekwondo athletes divided into International/National (median [interquartile range]; n = 21, age: 20 [18–25] years; body ...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

The Match Heart Rate and Running Profile of Elite Under-21 Hurlers During Competitive Match-Play
Young, D, Mourot, L, Beato, M, and Coratella, G. The match heart rate and running profile of elite under-21 hurlers during competitive match-play. J Strength Cond Res 32(10): 2925–2933, 2018—The aims of the current study were to examine the physical and physiological demands of elite under-21 male hurling match-play across halves of play and between positions. Global positioning systems (10 Hz) and heart rate (HR) monitors were used to collect data from 95 players during 10 games. Total distance (TD), relative speed, high-speed running (HSR), sprint distance, total sprints, and mean length of sprint was 6,688 &...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Running Intensities in Elite Youth Soccer by Age and Position
Duthie, GM, Thornton, HR, Delaney, JA, Connolly, DR, and Serpiello, FR. Running intensities in elite youth soccer by age and position. J Strength Cond Res 32(10): 2918–2924, 2018—The purpose of this investigation was to examine differences between the peak running speed, acceleration, and metabolic power of elite youth soccer across a range of age levels by position. Ninety-six elite junior soccer players were assessed between 2015 and 2017. Ninety-six elite junior soccer players (at time of match: age, 15.8 ± 0.9 years; body mass, 69.1 ± 8.0 kg) were assessed during 61 games within the 2015, 2016...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Match Demands of National Collegiate Athletic Association Division I Men's Soccer
This study aimed to profile positional movement characteristics of National Collegiate Athletic Association (NCAA) Division I male soccer players. Eighteen Division I male soccer players were monitored using global positioning systems, inertial movement, and heart rate (HR) technology during 24 matches over a full competitive season (N = 235 observations). Positional groups were classified as either a forward (F), center midfielder (CM), wide midfielder (WM), or defender (D). Movement was profiled by locomotor (walking [0–7.19 km·h−1], jogging [7.20–14.39 km·h−1], running [14.40–...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Laboratory-Based Physical and Physiological Test Results That Serve as Predictors of Male, Amateur Road Cyclists' Performance Levels
Coetzee, B, and Malan, D. Laboratory-based physical and physiological test results that serve as predictors of male, amateur road cyclists' performance levels. J Strength Cond Res 32(10): 2897–2906, 2018—The purposes of this study were first, to determine the practical significant differences of laboratory-based physical and physiological test results between a selected group of successful and less successful amateur, male road cyclists from Africa; and second, to determine the significance, adequacy, accurateness, and usefulness of laboratory-based physical and physiological test results to serve as predictors...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Examining the Influence of Exercise Intensity and Hydration on Gastrointestinal Temperature in Collegiate Football Players
DeMartini-Nolan, JK, Martschinske, JL, Casa, DJ, Lopez, RM, Stearns, RL, Ganio, MS, and Coris, E. Examining the influence of exercise intensity and hydration on gastrointestinal temperature in collegiate football players. J Strength Cond Res 32(10): 2888–2896, 2018—Debate exists regarding the influence of intensity and hydration on body temperature during American football. The purpose of this study was to observe body core temperature responses with changes in intensity and hydration. Twenty-nine male football players (age = 21 ± 1 year, height = 187 ± 9 cm, mass = 110.1 ± 23.5 kg, body ma...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Efficacy of Hot Yoga as a Heat Stress Technique for Enhancing Plasma Volume and Cardiovascular Performance in Elite Female Field Hockey Players
Perrotta, AS, White, MD, Koehle, MS, Taunton, JE, and Warburton, DER. Efficacy of hot yoga as a heat stress technique for enhancing plasma volume and cardiovascular performance in elite female field hockey players. J Strength Cond Res 32(10): 2878–2887, 2018—This investigation examined the efficacy of hot yoga as an alternative heat stress technique for enhancing plasma volume percentage (PV%) and cardiovascular performance. Ten international caliber female field hockey players completed six 60-minute hot yoga sessions using permissive dehydration over 6 days, followed by a 6-day national team camp. Changes in ...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Consumption of a 5-mg Melatonin Supplement Does Not Affect 32.2-km Cycling Time Trial Performance
Brandenberger, KJ, Ingalls, CP, Rupp, JC, and Doyle, JA. Consumption of a 5-mg melatonin supplement does not affect 32.2-km cycling time trial performance. J Strength Cond Res 32(10): 2872–2877, 2018—Some studies suggest that exogenous melatonin supplementation may improve athletic performance in hot humid environments because of its precooling effect. However, melatonin is also consumed as a sleep aid for its depressive effects on the central nervous system (CNS), which may hinder performance. Therefore, this study was conducted to determine whether consuming a 5-mg supplement of melatonin would affect perform...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Effect of Caffeine Supplementation on Quadriceps Performance After Eccentric Exercise
This study examined the effect of caffeine supplementation on uninjured and injured muscle. Eight men and women (N = 16) who were physically active individuals participated in this study (age: 24.3 ± 4.3 years; height: 173.0 ± 7.0 cm, mass: 75.2 ± 11.5 kg; body fat: 18.2 ± 15.9%). One leg was assessed under uninjured and injured (100 eccentric quadriceps contractions) conditions after caffeine supplementation (6 mg·kg−1), with the other leg assessed under both conditions after placebo supplementation. Compared with the placebo, caffeine increased peak isokinetic torque by 6.8 &plusm...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

The Perceived Psychological Responsibilities of a Strength and Conditioning Coach
Radcliffe, JN, Comfort, P, and Fawcett, T. The perceived psychological responsibilities of a strength and conditioning coach. J Strength Cond Res 32(10): 2853–2862, 2016—Research is limited in exploring the specific psychology-oriented responsibilities of the strength and conditioning professional. The present research explored the psychological responsibilities adopted by accredited strength and conditioning coaches. Participants comprised 10 coaches working within the United Kingdom, 3 within the United States, and 5 within Australia offering a cross-section of experience from various sport disciplines and ed...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

An Eighteen-Minute Submaximal Exercise Test to Assess Cardiac Fitness in Response to Aerobic Training
Romagnoli, M, Alis, R, Sanchis-Gomar, F, Lippi, G, and Arduini, A. An 18-minute submaximal exercise test to assess cardiac fitness in response to aerobic training. J Strength Cond Res 32(10): 2846–2852, 2018—We aimed to evaluate the utility of a submaximal heart rate recovery (HRR) test to monitor changes in cardiac fitness after aerobic training. Twenty healthy subjects were assigned to a control (n = 10) or a training (n = 10) group. Subjects in the training group performed 8 weeks of bicycle training, followed by 8 weeks of detraining. Heart rate recovery was assessed after exercises at 65% and 80% HRmax. Th...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Novel Technologies Found to be Valid and Reliable for the Measurement of Vertical Jump Height With Jump-and-Reach Testing
Brooks, ER, Benson, AC, and Bruce, LM. Novel technologies found to be valid and reliable for the measurement of vertical jump height with jump-and-reach testing. J Strength Cond Res 32(10): 2838–2845, 2018—Vertical jump testing is used by coaches and athletes across many sports and disciplines to assess lower-body power and neuromuscular fatigue. A range of devices are available to measure jump height, with recent innovations attempting to improve portability, usability, and accessibility. New devices should be evaluated for their effectiveness and dependability in specific tests before being adopted. The purpo...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Validity and Reliability of Global Positioning System Units (STATSports Viper) for Measuring Distance and Peak Speed in Sports
Beato, M, Devereux, G, and Stiff, A. Validity and reliability of global positioning system units (STATSports Viper) for measuring distance and peak speed in sports. J Strength Cond Res 32(10): 2831–2837, 2018—Previous evidence has proven that large variability exists in the accuracy of different brands of global positioning systems (GPS). Therefore, any GPS model should be validated independently, and the results of a specific brand cannot be extended to others. The aim of this study is to assess the validity and reliability of GPS units (STATSports Viper) for measuring distance and peak speed in sports. Twenty...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Cardiac Autonomic and Blood Pressure Responses to an Acute Foam Rolling Session
This study evaluated the effects of an acute session of FR exercise on heart rate variability (HRV) and BP responses in healthy individuals. Fifteen (M = 8, F = 7) healthy subjects completed either an FR or nonexercise control trial in randomized order. Heart rate variability and BP measurements were collected at baseline, 10, and 30 minutes after each trial. There were significant increases (p (Source: Journal of Strength and Conditioning Research)
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Low Energy Availability, Plasma Lipids, and Hormonal Profiles of Recreational Athletes
This study describes the lipid levels, hormonal profiles, and nutrient intakes of recreationally active adults at risk of LEA compared with those not at risk. Thirty-eight women who meet or exceed the New Zealand guidelines for physical activity participated. Each participant completed an online questionnaire including the Low Energy Availability in Females questionnaire (LEAF-Q), demographic questions, and daily exercise to determine energy expenditure. Participants also provided a weighed 3-day diet record, a blood sample analyzed for total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein choles...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Photobiomodulation Therapy on Physiological and Performance Parameters During Running Tests: Dose–Response Effects
This study was aimed at verifying effects of photobiomodulation therapy (PBMT) with different energy doses (15, 30, and 60 J per site) on physiological and performance parameters during running tests. Fifteen male recreational runners participated in a crossover, randomized, double-blind, and placebo-controlled trial. They performed testing protocol in 5 sessions with different treatments: control, placebo, and PBMT with 15, 30, or 60 J per site (14 sites in each lower limb). Physiological and performance variables were assessed during submaximal (at 8 and 9 km·h−1) and maximal running tests. Photobiomodulatio...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Mixed Session Periodization as a New Approach for Strength, Power, Functional Performance, and Body Composition Enhancement in Aging Adults
Berzerra, ES, Orssatto, LBR, Moura, BM, Willardson, JM, Simão, R, and Moro, ARP. Mixed session periodization as a new approach for strength, power, functional performance, and body composition enhancement in aging adults. J Strength Cond Res 32(10): 2795–2806, 2018—The purpose of this study was to compare the effects of mixed session periodization (MSP) vs. traditional periodization (TP) on strength, power, functional performance, and body composition in aging adults. Forty-five healthy aging adults were randomly divided into 3 groups: MSP, TP, and Control. Subjects were tested before the intervention fo...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Test-Retest Reliability and Concurrent Validity of Athletic Performance Combine Tests in 6–15-Year-Old Male Athletes
Gillen, ZM, Miramonti, AA, McKay, BD, Leutzinger, TJ, and Cramer, JT. Test-retest reliability and concurrent validity of athletic performance combine tests in 6–15-year-old male athletes. J Strength Cond Res 32(10): 2783–2794, 2018—Athletic performance combine tests are used by high school, collegiate, and professional American football programs to evaluate performance; however, limited evidence is available on performance combine test results in youth athletes. The purposes of this study were to report test-retest reliability statistics and evaluate concurrent validity among combine performance tests in ...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Individual and Combined Influence of ACE and ACTN3 Genes on Muscle Phenotypes in Polish Athletes
Orysiak, J, Mazur-Różycka, J, Busko, K, Gajewski, J, Szczepanska, B, and Malczewska-Lenczowska, J. Individual and combined influence of ACE and ACTN3 genes on muscle phenotypes in polish athletes. J Strength Cond Res 32(10): 2776–2782, 2018—The aim of this study was to examine the association between angiotensin-converting enzyme (ACE) and α-actinin-3 (ACTN3) genes, independently or in combination, and muscle strength and power in male and female athletes. The study involved 398 young male (n = 266) and female (n = 132) athletes representing various sport disciplines (ice hockey, canoeing, swimmin...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Muscle Activation Patterns of Lower-Body Musculature Among 3 Traditional Lower-Body Exercises in Trained Women
Korak, JA, Paquette, MR, Fuller, DK, Caputo, JL, and Coons, JM. Muscle activation patterns of lower-body musculature among 3 traditional lower-body exercises in trained women. J Strength Cond Res 32(10): 2770–2775, 2018—The deadlift and back and front squats are common multijoint, lower-body resistance exercises that target similar musculature. To our knowledge, muscle activity measured using surface electromyography has never been analyzed among these 3 exercises. Furthermore, most literature examining this topic has included male participants creating a void in the literature for the female population. Knowle...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of 12-Week Resistance Training on Sprint and Jump Performances in Competitive Adolescent Rugby Union Players
Harries, SK, Lubans, DR, Buxton, A, MacDougall, THJ, and Callister, R. Effects of 12-week resistance training on sprint and jump performances in competitive adolescent rugby union players. J Strength Cond Res 32(10): 2762–2769, 2018—Sprint performance is an important characteristic for success in many sports, including rugby union. Resistance training is used to increase muscular fitness (i.e., strength, endurance, and power) and may also be effective for improving sprint and jump performances. The aims of this study were to examine the effects of resistance training using 2 different periodized programs (linea...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Effects of Accentuated Eccentric Loading on Muscle Properties, Strength, Power, and Speed in Resistance-Trained Rugby Players
Douglas, J, Pearson, S, Ross, A, and McGuigan, M. Effects of accentuated eccentric loading on muscle properties, strength, power, and speed in resistance-trained rugby players. J Strength Cond Res 32(10): 2750–2761, 2018—The purpose of this study was to determine the effects of slow and fast tempo resistance training incorporating accentuated eccentric loading (AEL) compared with traditional resistance training (TRT) in trained rugby players. Fourteen subjects (19.4 ± 0.8 years, 1.82 ± 0.05 m, 97.0 ± 11.6 kg, and relative back squat 1 repetition maximum [1RM]: 1.71 ± 0.24 kg·B...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

A Comparison of the Effects of Short-Term Plyometric and Resistance Training on Lower-Body Muscular Performance
Whitehead, MT, Scheett, TP, McGuigan, MR, and Martin, AV. A comparison of the effects of short-term plyometric and resistance training on lower-body muscular performance. J Strength Cond Res 32(10): 2743–2749, 2018—The purpose of this study was to compare effects of short-term plyometric and resistance training on lower-body muscular performance. A convenience sample of 30 male subjects aged 21.3 ± 1.8 years (height, 177.3 ± 9.4 cm; mass, 80.0 ± 2.6 kg; body fat, 16.1 ± 1.2%) participated in this investigation. Participants were grouped, and they participated in progressive plyometri...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Whole-Body High-Intensity Interval Training Induce Similar Cardiorespiratory Adaptations Compared With Traditional High-Intensity Interval Training and Moderate-Intensity Continuous Training in Healthy Men
Schaun, GZ, Pinto, SS, Silva, MR, Dolinski, DB, and Alberton, CL. Sixteen weeks of whole-body high-intensity interval training induce similar cardiorespiratory responses compared with traditional high-intensity interval training and moderate-intensity continuous training in healthy men. J Strength Cond Res 32(10): 2730–2742, 2018—Low-volume high-intensity interval training (HIIT) protocols that use the body weight as resistance could be an interesting and inexpensive alternative to traditional ergometer-based high-intensity interval training (HIIT-T) and moderate-intensity continuous training (MICT). Therefore,...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Warm-up Optimizes Postural Control but Requires Some Minutes of Recovery
Paillard, T, Kadri, MA, Nouar, MB, and Noé, F. Warm-up optimizes postural control but requires some minutes of recovery. J Strength Cond Res 32(10): 2725–2729, 2018—The aim was to compare monopedal postural control between the dominant leg (D-Leg) and the nondominant leg (ND-Leg) in pre– and post–warm-up conditions. Thirty healthy male sports science students were evaluated before and after a warm-up exercise (12 minutes of pedaling with an incremental effort on a cycle ergometer with a controlled workload). Monopodal postural control was assessed for the D- and ND-Legs before and immediately...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research

Eight-Week Battle Rope Training Improves Multiple Physical Fitness Dimensions and Shooting Accuracy in Collegiate Basketball Players
This study investigated whether battle rope (BR) training enhances multiple physical fitness dimensions, including aerobic capacity (AC), upper-body anaerobic power (AnP), upper-body and lower-body power, agility, and core muscle endurance, and shooting accuracy in basketball players and compared its effects with those of regular training (shuttle run [SR]). Thirty male collegiate basketball players were randomly assigned to the BR or SR groups (n = 15 per group). Both groups received 8-week interval training for 3 sessions per week; the protocol consisted of the same number of sets, exercise time, and rest interval time. ...
Source: Journal of Strength and Conditioning Research - September 22, 2018 Category: Sports Medicine Tags: Original Research Source Type: research