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β-Alanine is one of the more popular sport supplements used by strength/power athletes today. The popularity of β-alanine stems from its ability to enhance intracellular muscle-buffering capacity thereby delaying fatigue during high-intensity exercise by increasing muscle carnosine content. Recent evidence also suggests that elevated carnosine levels may enhance cognitive performance and increase resiliency to stress. These benefits are thought to result from carnosine's potential role as an antioxidant. This review will discuss these new findings including recent investigations examining β-alanine supplementation and increased resiliency to posttraumatic stress and mild traumatic brain injury. This review will focus on the physiology of carnosine, the effect of β-alanine ingestion on carnosine elevations, and the potential ergogenic benefits it has for competitive and tactical athletes.

Background Guanidinoacetic acid (GAA), a natural precursor of creatine, is a new promising dietary supplement, yet its performance-enhancing effect, if any, has yet to be established. The purpose of this pilot study was to evaluate the effects of supplemental GAA on muscle strength, anaerobic performance, and aerobic performance in healthy men and women. Method The study enrolled 48 young participants (age, 22.3 ± 1.5 years; height, 176.4 ± 10.0 cm; weight, 71.9 ± 14.3 kg), who received oral doses of GAA (1.2, 2.4, or 4.8 g/d) for 6 weeks in a randomized, double-blind, placebo-controlled trials. Results Significant differences were observed between treatment groups for handgrip strength among participants receiving 1.2 g of GAA per day and 2.4 g of GAA per day, as compared with placebo ( P < 0.05). In addition, muscle endurance expressed as the change from baseline in repetitions performed in the bench press exercise was significantly greater in the 1.2 g/d dose of GAA ( P = 0.01) and the 4.8 g/d dose ( P = 0.01) compared with placebo. No dose-response differences were found between trials. Conclusions Results from this preliminary study indicate that supplemental GAA ingested in young individuals can improve exercise performance, even at low doses (1.2 g/d).

In January 2012, the National Athletic Trainers' Association, along with the National Strength and Conditioning Association, convened a meeting in Colorado Springs, Colorado. Its purpose was to hold an interdisciplinary forum and gather input to address sudden death in collegiate conditioning sessions. Based on these discussions, a writing group drafted the following recommendations. To date, these best practices have been endorsed by the American College of Emergency Physicians, American College of Sports Medicine, American Medical Society for Sports Medicine, American Osteopathic Academy of Sports Medicine, Canadian Athletic Therapists' Association, Collegiate Strength and Conditioning Coaches association, Gatorade Sports Science Institute, Korey Stringer Institute, National Academy of Sports Medicine, National Athletic Trainers' Association, and National Strength and Conditioning Association. Other reviewers and meeting participants are listed with the professional organizations they represent at the end of this article. Maximizing strength and conditioning sessions has become fundamental to sport. The right combination of strength, speed, cardiorespiratory fitness, and other components of athletic capacity can complement skill and enhance performance for all athletes. A sound and effective training program that relies on scientific principles of exercise physiology and biomechanics intended to produce outcomes that are sensitive and specific to the sport should be the goals. Unfortunately, the athlete's development, health, and safety are sometimes overshadowed by a culture that values making athletes tough, instilling discipline, and focusing on success at all costs. This ill-conceived philosophy has been a contributor to the alarming increase in collegiate athlete deaths and serious injuries during conditioning sessions. A total of 21 National Collegiate Athletic Association (NCAA) football players have died during conditioning workouts since 2000.1 The 3 most common causes of the fatalities were (in order) exercise-related sudden death associated with sickle cell trait (SCT), exertional heat stroke, and cardiac conditions.1 Seventy-five percent of the fatalities (n = 16) were Division I football players. Also, the incidence of exertional rhabdomyolysis in collegiate athletes appears to be increasing. Excesses in strength training and conditioning—workouts that are too novel, too much, too soon, or too intense (or a combination of these)—have a strong connection to exertional rhabdomyolysis. Introducing full-intensity workouts too quickly is especially high risk: 11 of the 21 deaths occurred during day 1 or day 2 workouts. Rule changes enacted in 2003 related to heat acclimatization procedures during August football practices have been extremely effective. In the NCAA Division I Football Bowl Subdivision, no player died from practicing or playing in a game between 2000 and 2011. However, conditioning workouts continue to be a catalyst for catastrophic outcomes. It is imperative that similar guidelines be implemented to improve the safety of conditioning sessions. This consensus statement provides specific conditioning recommendations with the intent of ending conditioning-related morbidity and deaths of collegiate athletes.

The effect of altitude on soccer game activity profiles was retrospectively examined in six NCAA Division I female soccer players. Comparisons were made between two matches played at sea level (SL) and one match played at a moderate altitude (1839 m). A 10-Hz global positioning system device was used to measure distance and velocity. The rate of total distance capacity (TDC) and high intensity running (HIR) as well as percent of time at HIR were evaluated. Significant differences were seen in the distance rate (120.55 ± 8.26 m·min-1 versus 105.77 ± 10.19 m·min-1) and the HIR rate (27.65 ± 9.25 m·min-1 versus 25.07 ± 7.66 m·min-1) between SL and altitude, respectively. The percent of time at HIR was not significantly different (p = 0.064), yet tended to be greater at SL (10.4 ± 3.3%) than at altitude (9.1 ± 2.2%). Results indicate that teams residing at SL and competing at a moderate altitude may have a reduced ability in distance covered and a high intensity run rate.

The amount of training days lost to injury during military training has highlighted the need to identify a screening tool to predict injury. One hundred and fifty-eight female soldiers from the Combat Fitness Instructor Course (CFIC) of the Israel Defense Forces volunteered to participate in this study. All soldiers were free of orthopedic and neurologic conditions for at least one month before the study. All participants performed a battery of measurements during the first week of the course. Measures included anthropometric, functional movement screen (FMS), power performances (counter movement jump [CMJ], drop jump, single leg triple hop jump [SLTH], 10-m sprint) and a 2K run. Injury data was collected throughout the 3 month course. Median tests were used to compare between injured/non-injured soldiers. Chi-square and/or logistic regression analysis was used to examine the association between various predictors and injury. Percent body fat [%BF] was higher (p = 0.04), distance for SLTH was less for both left and right legs (p = 0.029, p = 0.047 respectively) and 2K run was slower (p =0.044) in injured compared to non-injured soldiers. No differences between groups were noted in total FMS score, however more zero scores in one or more movement pattern were found in the injured group (51.35 % vs. 30.5% p=0.0293). Only %BF, 2K run and SLTH distance were significant predictors of injury (p = 0.05, p = 0.02, p =0.016 respectively). The results of this study indicated that the FMS total score is not a predictor of injury in female soldiers in a CFIC. We found that %BF, SLTH, 2K run time, 10 meter sprint time and zero scores differentiated between injured and non-injured soldiers. In addition, %BF, 2K run and SLTH were each found to be separate predictors of injury. Further research is needed to determine threshold scores that predict injury.

During sustained high-intensity military training or simulated combat exercises, significant decreases in physical performance measures are often seen. The use of dietary supplements is becoming increasingly popular among military personnel, with more than half of the US soldiers deployed or garrisoned reported to using dietary supplements. β-Alanine is a popular supplement used primarily by strength and power athletes to enhance performance, as well as training aimed at improving muscle growth, strength and power. However, there is limited research examining the efficacy of β-alanine in soldiers conducting operationally relevant tasks. The gains brought about by β-alanine use by selected competitive athletes appears to be relevant also for certain physiological demands common to military personnel during part of their training program. Medical and health personnel within the military are expected to extrapolate and implement relevant knowledge and doctrine from research performed on other population groups. The evidence supporting the use of β-alanine in competitive and recreational athletic populations suggests that similar benefits would also be observed among tactical athletes. However, recent studies in military personnel have provided direct evidence supporting the use of β-alanine supplementation for enhancing combat-specific performance. This appears to be most relevant for high-intensity activities lasting 60-300 s. Further, limited evidence has recently been presented suggesting that β-alanine supplementation may enhance cognitive function and promote resiliency during highly stressful situations.

The purpose of this study was to investigate the effects of short term resistance exercise on neuromuscular fatigue threshold (PWCFT), strength, functional performance, and body composition in older adults. Twenty-three participants (71.2 ± 6.0 yr) were randomly assigned to 6 weeks of resistance exercise (EXE) or control (CONT). A submaximal cycle ergometer test, physical working capacity at fatigue threshold, was used to determine PWCFT. Strength was assessed with predicted leg extension 1-RM and functional performance with time to complete 5 chair rises (CHAIR) and walk an 8-ft course (WALK). PWCFT, 1-RM and CHAIR significantly (p

To examine the efficacy of l-alanyl-l-glutamine ingestion with a commercially available sports drink compared to the sports drink only on time to exhaustion and physiological measures during prolonged endurance exercise.Twelve endurance-trained men (23.5 ± 3.7 years; 175.5 ± 5.4 cm; 70.7 ± 7.6 kg) performed 4 trials, each consisting of a 1-hour treadmill run at 75% VO2peak followed by a run to exhaustion at 90% VO2peak. One trial consisted of no hydration (NHY), another required ingestion of only a sports drink (ED), and 2 trials required ingestion of a low dose (LD; 300 mg·500 ml(-1)) and high dose (HD) of l-alanyl-l-glutamine (1 g·500 ml(-1)) added to the sports drink. During the fluid ingestion trials, 250 ml was consumed every 15 minutes. Plasma glutamine, glucose, electrolytes, and osmolality were measured prior to the run (PRE) and at 30, 45, and 60 minutes. VO2, respiratory quotient (RQ), and heart rate (HR) were measured every 15 minutes.Time to exhaustion was significantly longer during the LD and HD trials compared to NHY. No differences were noted in time to exhaustion between ED and NHY. Plasma glutamine concentrations were significantly elevated at 45 minutes in LD and HD trials and remained elevated at 60 minutes during HD. Sodium concentrations increased from the beginning of exercise and remained stable for the duration of the 1-hour run. At 60 minutes, plasma sodium was significantly lower in all trials compared to NHY.Results indicated that ingestion of the alanine-glutamine dipeptide at either the low or high dose significantly improved time to exhaustion during high-intensity exercise compared to a no-hydration trial.

To evaluate the time course of EMG frequency changes during a three-minute maximal effort cycling test (3MT) session and to examine which parameter between mean (MNF) and median (MDF) frequency is more suitable for evaluation of changes in neuromuscular function throughout a 3MT. Eighteen recreationally-active men volunteered to participate in this study. Maximum voluntary contraction (MVC) was measured using a dynamometer to determine maximal EMG frequency of the vastus lateralis (VL) of the kicking leg during isometric knee extension. A maximal oxygen consumption test (VO2peak) on a cycle ergometer was performed to establish the appropriate load profile for the 3MT which was completed after a period of at least 48 hours. MNF, MDF and power output (PO) values were measured at 10-second epochs throughout the duration of the 3MT. Repeated measures analysis of variance was used to compare the changes in EMG frequency, relative to maximal values from the MVC, and change in PO during the testing procedure. MNF, Root Mean Square (RMS), and PO significantly decreased during the 3MT, while MDF did not change significantly. Statistically, EMG frequency and PO decreased at first and remained constant in response to the 3MT, which may be reflective of differing patterns of muscle fiber type fatigue throughout the testing session. Due to decreased variability, changes in neuromuscular function during this protocol may be better evaluated using MNF than MDF.

This study compared caffeine pharmacokinetics, glycerol concentrations, metabolic rate, and performance measures following ingestion of a time-release caffeine containing supplement (TR-CAF) versus a regular caffeine capsule (CAF) and a placebo (PL). Following a double-blind, placebo-controlled, randomized, cross-over design, ten males (25.9 ± 3.2 y) who regularly consume caffeine ingested capsules containing either TR-CAF, CAF, or PL. Blood draws and performance measures occurred at every hour over an 8-hour period. Plasma caffeine concentrations were significantly greater (p < 0.05) in CAF compared to TR-CAF during hours 2-5 and significantly greater (p = 0.042) in TR-CAF compared to CAF at hour 8. There were no significant differences between trials in glycerol concentrations (p = 0.86) or metabolic measures (p = 0.17-0.91). Physical reaction time was significantly improved for CAF at hour 5 (p=0.01) compared to PL. Average upper body reaction time was significantly improved for CAF and TR-CAF during hours 1-4 (p = 0.04 and p = 0.01, respectively) and over the 8-hour period (p = 0.04 and p = 0.001, respectively) compared to PL. Average upper body reaction time was also significantly improved for TR-CAF compared to PL during hours 5-8 (p = 0.004). TR-CAF and CAF showed distinct pharmacokinetics yielding modest effects on reaction time, yet did not alter glycerol concentration, metabolic measures, or other performance measures.

Purpose:During the competitive soccer season, women’s intercollegiate matches are typically played on Friday evenings and Sunday afternoons. The efficacy of a 42-h recovery period is not well understood. This investigation was conducted to determine performance differences between Friday and Sunday matches during a competitive season.Methods:Ten NCAA Division I female soccer players (20.5 ± 1.0 y, 166.6 ± 5.1 cm, 61.1 ± 5.8 kg) were monitored with 10-Hz GPS devices across 8 weekends with matches played on Friday evenings and Sunday afternoons. The players were outside backs, midfielders, and forwards. All players had to participate in a minimum of 45 min/match to be included in the study. Average minutes played, total distance covered, total distance of high-intensity running (HIR) (defined as running at a velocity equal to or exceeding 3.61 m/s for longer than 1 s), the number of HIR efforts, and the number of sprints were calculated for each match. Data for Friday vs Sunday matches were averaged and then compared using dependent t tests.Results:No differences were seen in minutes played, distance rate, or number of sprints between Friday and Sunday matches. A significant (P = .017) decrease in rate of HIR between Friday (25.37 ± 7.22 m/min) and Sunday matches (22.90 ± 5.70 m/min) was seen. In addition, there was a trend toward a difference (P = .073) in the number of efforts of HIR between Friday (138.41 ± 36.43) and Sunday (126.92 ± 31.31).Conclusions:NCAA Division I female soccer players cover less distance of HIR in games played less than 48 h after another game. This could be due to various factors such as dehydration, glycogen depletion, or muscle damage.

Context:Resistance training is a common form of exercise for competitive and recreational athletes. Enhancing recovery from resistance training may improve the muscle-remodeling processes, stimulating a faster return to peak performance.Objective:To examine the effects of 2 different recovery modalities, neuromuscular electrical stimulation (NMES) and cold-water immersion (CWI), on performance and biochemical and ultrasonographic measures.Participants:Thirty resistance-trained men (23.1 ± 2.9 y, 175.2 ± 7.1 cm, 82.1 ± 8.4 kg) were randomly assigned to NMES, CWI, or control (CON).Design and Setting:All participants completed a high-volume lower-body resistance-training workout on d 1 and returned to the human performance laboratory 24 (24H) and 48 h (48H) postexercise for follow-up testing.Measures:Blood samples were obtained preexercise (PRE) and immediately (IP), 30 min (30P), 24 h (24H), and 48 h (48H) post. Subjects were examined for performance changes in the squat exercise (total repetitions and average power per repetition), biomarkers of inflammation, and changes in cross-sectional area and echo intensity (EI) of the rectus femoris (RF) and vastus lateralis muscles.Results:No differences between groups were observed in the number of repetitions (P = .250; power: P = .663). Inferential-based analysis indicated that increases in C-reactive protein concentrations were likely increased by a greater magnitude after CWI compared with CON, while NMES possibly decreased more than CON from IP to 24H. Increases in interleukin-10 concentrations between IP and 30P were likely greater in CWI than NMES but not different from CON. Inferential-based analysis of RF EI indicated a likely decrease for CWI between IP and 48H. No other differences between groups were noted in any other muscle-architecture measures.Conclusions:Results indicated that CWI induced greater increases in pro- and anti-inflammatory markers, while decreasing RF EI, suggesting that CWI may be effective in enhancing short-term muscle recovery after high-volume bouts of resistance exercise.

Bartolomei, S, Hoffman, JR, Stout, JR, and Merni, F. Effect of lower-body resistance training on upper-body strength adaptation in trained men. J Strength Cond Res 32(1): 13-18, 2018-The aim of this study was to examine the effect of 2 different lower-body strength training schemes on upper-body adaptations to resistance training. Twenty resistance-trained men (4.25 ± 1.6 years of experience) were randomly assigned to either a high intensity (HI; n = 9; age = 24.9 ± 2.9 years; body mass = 88.7 ± 17.2 kg; height = 177.0 ± 5.6 cm) or a mixed high volume and HI resistance training program (MP; n = 11; age = 26.0 ± 4.7 years; body mass = 82.8 ± 9.1 kg; height = 177.54 ± 5.9 cm). High-intensity group followed a HI training for both upper and lower body (4-5 reps at 88%-90% of 1 repetition maximum (1RM)), whereas the MP group performed high-volume training sessions focused on muscle hypertrophy for lower body (10-12 reps at 65%-70% of 1-RM) and a HI protocol for the upper body. Maximal strength and power testing occurred before and after the 6-week training program. Analysis of covariance was used to compare performance measures between the groups. Greater increases in MP groups compared with HI groups were observed for bench press 1RM (p = 0.007), bench press power at 50% of 1RM (p = 0.011), and for arm muscle area (p = 0.046). Significant difference between the 2 groups at posttest were also observed for fat mass (p = 0.009). Results indicated that training programs focused on lower-body muscle hypertrophy and maximal strength for upper body can stimulate greater strength and power gains in the upper body compared with HI resistance training programs for both the upper and lower body.

Purpose To evaluate the effects of moderate normobaric hypoxia on the parameters of the work-time relationship in the upper body. Methods Twenty-one recreationally active men completed a graded exercise test in both normobaric hypoxia (H) and normoxia (N) to exhaustion on an arm ergometer to determine VO2peak and peak power output (PPO). Each participant completed four constant work-rate (CWR) arm-cranking tests at 90–120% PPO in both environmental conditions. Linear regression was used to estimate critical power (CP) and anaerobic working capacity (AWC) via work-time relationship during the CWR tests. Results H significantly reduced VO2peak (N: 2.34 ± 0.34 L vs. H: 2.27 ± 0.34 L, p = 0.041), PPO (N: 125.29 ± 17.98 W vs. H: 121.11 ± 17.98 W, p = 0.001), and CP (N: 90.22 ± 12.88 W vs. H: 85.26 ± 9.64 W, p = 0.042), but had no effect on AWC (N: 9.16 ± 2.81 kJ vs. H: 8.75 ± 3.23 kJ, p = 0.600). Discussion Moderate normobaric hypoxia appears to reduce CP in the upper body but has a variable effect on AWC.

Tumor necrosis factor-alpha (TNF-α) has been shown to be implicated in both muscle regeneration and muscle wasting. However, it remains unclear whether TNF-α is responsible for the age-related losses in muscle size and function. Also, due to the high clearance rate of TNF-α from circulation, analyzing the circulating levels of soluble TNF-α receptors 1 and 2 (STNFR1 and STNFR2) may provide a better indication of inflammatory events. The aim of this study was to examine changes in circulating concentrations of TNF-α, STNFR1, and STNFR2 following acute eccentric exercise in young (YA) and middle-aged (MA) men.Nine YA (N=9, 21.8±2.2y, 179.5±4.9cm, 91.2±12.2kg, 21.8±4.3% body fat) and ten MA (N=10, 47.0±4.4y, 176.8±7.6cm; 96.0±21.5kg, 25.4±5.3% body fat) men completed an acute muscle damaging protocol (MDP). Blood samples were obtained at baseline (BL), immediately (IP), 30-minute (30P), 60-minute (60P), 120-minute (120P), 24-hour (24H), and 48-hour (48H) post-MDP. Lower body performance was assessed via isokinetic dynamometer at BL, IP, 120P, 24H, and 48H.YA displayed higher values of peak torque (p=0.023) and mean torque (p=0.036) at BL. No significant group differences were observed for markers of muscle damage or TNF-α. Plasma concentrations of TNF-α were unchanged following MDP. STNFR1 concentrations were significantly higher in the YA group compared to MA (p=0.036). Significant time effects were observed for STNFR1 (p0.001) and STNFR2 (p=0.001). With both groups combined, serum STNFR1 was decreased at 30P (p=0.001), while STNFR2 was decreased at 30P (p=0.008), 60P (p=0.003), and 120P (p=0.002) relative to BL.The pro-inflammatory response to muscle damage does not appear to decline at middle age when individuals are recreationally trained. However, young men showed significantly higher serum STNFR1 concentrations than middle age men. This may suggest that natural inhibitors of TNF-α decline as early as middle age.

β-Alanine (BA) supplementation results in elevated intramuscular carnosine content, enhancing buffering capacity during intense exercise. Although men have greater muscle carnosine content than women, elevations still appear to occur despite high baseline levels. Recent research has suggested that BA supplementation may also reduce muscle l-histidine. Thus, the purpose of this investigation was to compare 28 days of BA (6 g·d-1) supplementation in men and women on performance and muscle carnosine, l-histidine, and BA. We hypothesized that supplementation would result in similar elevations in carnosine and performance between sexes and decrease l-histidine. Twenty-six men and women were assigned either BA or placebo (PLA). At baseline, a trend toward greater carnosine (P = .069) was observed in men, and intramuscular BA content was significantly (P ≤ .05) greater in men. Statistical analysis was performed using magnitude-based inferences. Changes in muscle carnosine were likely and very likely greater after BA supplementation compared with PLA in men and women, respectively, but changes were unclear between sexes (mean sex difference: 2.50 ± 4.30 mmol·kg-1 ww). The attenuation of exercise fatigue was likely greater in BA compared with PLA, but the change was unclear between sexes (mean sex difference: 14.0 ± 39.0 Nm). Changes in muscle BA following supplementation was unclear in men, likely elevated in women, but unclear between sexes (mean sex difference: 0.03 ± 0.42 mmol·kg-1 ww). Changes in muscle l-histidine were unclear in men and women, and unclear between sexes (mean sex difference: 0.09 ± 0.13 mmol·kg-1 ww). In conclusion, BA supplementation increased muscle carnosine and attenuated fatigue in men and women similarly but did not reduce muscle l-histidine.

Heart rate deflection point (HRDP) can be determined through different mathematical-modeling procedures, such as bi-segmental linear regression (2SEG) or maximal distance model (Dmax). The purpose was to compare heart rate (HR) and oxygen consumption (VO2) at HRDP when using 2SEG and Dmax, and to examine their relationships with respiratory compensation point (RCP) and running performance. Nineteen participants completed a graded exercise test (GXT), to determine HRDP and RCP, and a 5km treadmill time trial (5Ktime). No differences were found in HR or VO2 when comparing HRDP2SEG, HRDPDmax, and RCP. Strong correlations were found between HRDP2SEG, HRDPDmax, and RCP when using HR and VO2. No relationships were found between 5Ktime and HR at HRDP or RCP; however, strong relationships were found with VO2. While 2SEG and Dmax may be interchangeable in determining HRDP, VO2 at HRDP and RCP yielded stronger relationships to 5Ktime than HR. Therefore, VO2 at HRDP may be a better predictor of running performance than HR.

BACKGROUND Intramyocellular triacylglycerol (IMTG) is utilized as metabolic fuel during exercise and is linked to insulin resistance, but the long-term effect of weight loss strategies on IMTG among participants with abdominal fat, remain unclear. METHODS In an 18-month trial, sedentary participants with abdominal fat/dyslipidemia were randomized to either a low-fat (LF) or Mediterranean/low-carbohydrate (MED/LC) diet (including 28g·day-1 of walnuts). After 6-months, the participants were re-randomized to moderate intense physical activity (PA+) or non-physical activity (PA-). Magnetic resonance imaging (MRI) was used to quantify changes of IMTG, abdominal sub-depots, hepatic and intermuscular fats. RESULTS Across the 277 participants [86% men, age = 48 years, body-mass-index (BMI) = 31kg/m2, visceral fat = 33%] 86% completed the 18-m trial. At baseline, women had higher IMTG than men (3.4% vs. 2.3%, p

Attenuating TNFα/TNFr1 signaling in monocytes has been proposed as a means of mitigating inflammation. The purpose of this study was to examine the effects of a milk protein supplement on TNFα and monocyte TNFr1 expression. Ten resistance-trained men (24.7 ± 3.4 years; 90.1 ± 11.3 kg; 176.0 ± 4.9 cm) ingested supplement (SUPP) or placebo (PL) immediately post-exercise in a randomized, cross-over design. Blood samples were obtained at baseline (BL), immediately (IP), 30-min (30P), 1-h (1H), 2-h (2H), and 5-h (5H) post-exercise to assess plasma concentrations of myoglobin; tumor necrosis factor-alpha (TNFα); and expression of tumor necrosis factor receptor 1 (TNFr1) on classical, intermediate, and non-classical monocytes. Magnitude-based inferences were used to provide inferences on the true effects of SUPP compared to PL. Plasma TNFα concentrations were “likely attenuated” (91.6% likelihood effect) from BL to 30P in the SUPP group compared with PL (d = 0.87; mean effect: 2.3 ± 2.4 pg mL−1). TNFr1 expressions on classical (75.9% likelihood effect) and intermediate (93.0% likelihood effect) monocytes were “likely attenuated” from BL to 2H in the SUPP group compared with PL (d = 0.67; mean effect: 510 ± 670 RFU, and d = 1.05; mean effect: 2500 ± 2300 RFU, respectively). TNFr1 expression on non-classical monocytes was “likely attenuated” (77.6% likelihood effect) from BL to 1H in the SUPP group compared with PL (d = 0.69; mean effect: 330 ± 430 RFU). Ingestion of a milk protein supplement immediately post-exercise appears to attenuate both plasma TNFα concentrations and TNFr1 expression on monocyte subpopulations in resistance-trained men.

Wang, R, Hoffman, JR, Sadres, E, Bartolomei, S, Muddle, TWD, Fukuda, DH, and Stout, JR. Evaluating upper-body strength and power from a single test: the ballistic push-up. J Strength Cond Res 31(5): 1338–1345, 2017—The purpose of this study was to examine the reliability of the ballistic push-up (BPU) exercise and to develop a prediction model for both maximal strength (1 repetition maximum [1RM]) in the bench press exercise and upper-body power. Sixty recreationally active men completed a 1RM bench press and 2 BPU assessments in 3 separate testing sessions. Peak and mean force, peak and mean rate of force development, net impulse, peak velocity, flight time, and peak and mean power were determined. Intraclass correlation coefficients were used to examine the reliability of the BPU. Stepwise linear regression was used to develop 1RM bench press and power prediction equations. Intraclass correlation coefficient's ranged from 0.849 to 0.971 for the BPU measurements. Multiple regression analysis provided the following 1RM bench press prediction equation: 1RM = 0.31 × Mean Force − 1.64 × Body Mass + 0.70 (R2 = 0.837, standard error of the estimate [SEE] = 11 kg); time-based power prediction equation: Peak Power = 11.0 × Body Mass + 2012.3 × Flight Time − 338.0 (R2 = 0.658, SEE = 150 W), Mean Power = 6.7 × Body Mass + 1004.4 × Flight Time − 224.6 (R2 = 0.664, SEE = 82 W); and velocity-based power prediction equation: Peak Power = 8.1 × Body Mass + 818.6 × Peak Velocity − 762.0 (R2 = 0.797, SEE = 115 W); Mean Power = 5.2 × Body Mass + 435.9 × Peak Velocity − 467.7 (R2 = 0.838, SEE = 57 W). The BPU is a reliable test for both upper-body strength and power. Results indicate that the mean force generated from the BPU can be used to predict 1RM bench press, whereas peak velocity and flight time measured during the BPU can be used to predict upper-body power. These findings support the potential use of the BPU as a valid method to evaluate upper-body strength and power.

Wang, R, Hoffman, JR, Sadres, E, Bartolomei, S, Muddle, TWD, Fukuda, DH, and Stout, JR. Effects of different relative loads on power performance during the ballistic push-up. J Strength Cond Res 31(12): 3411-3416, 2017-The purpose of this investigation was to examine the effect of load on force and power performance during a ballistic push-up. Sixty (24.5 ± 4.3 years, 1.75 ± 0.07 m, and 80.8 ± 13.5 kg) recreationally active men who participated in this investigation completed all testing and were included in the data analysis. All participants were required to perform a 1 repetition maximum bench press, and ballistic push-ups without external load (T1), with 10% (T2) and 20% (T3) of their body mass. Ballistic push-ups during T2 and T3 were performed using a weight loaded vest. Peak and mean force, power, as well as net impulse and flight time were determined for each ballistic push-up. Peak and mean force were both significantly greater (p < 0.01) during T3 (1,062 ± 202 and 901 ± 154 N, respectively), than both T2 (1,017 ± 202 and 842 ± 151 N, respectively) and T1 (960 ± 188 and 792 ± 140 N, respectively). Peak and mean power were significantly greater (p < 0.01) during T1 (950 ± 257 and 521 ± 148 W, respectively), than both T2 (872 ± 246 and 485 ± 143 W, respectively) and T3 (814 ± 275 and 485 ± 162 W, respectively). Peak and mean power were greatest during T1, regardless of participants' strength levels. Significant (p < 0.01) greater net impulse and smaller peak velocity and flight time were also noted from T1 to T3. Results of this investigation indicated that maximal power outputs were achieved without the use of an external load when performing the ballistic push-up, regardless of the participants' level of strength.

Position statement The International Society of Sports Nutrition (ISSN) provides an objective and critical review related to the intake of protein for healthy, exercising individuals. Based on the current available literature, the position of the Society is as follows:An acute exercise stimulus, particularly resistance exercise, and protein ingestion both stimulate muscle protein synthesis (MPS) and are synergistic when protein consumption occurs before or after resistance exercise.For building muscle mass and for maintaining muscle mass through a positive muscle protein balance, an overall daily protein intake in the range of 1.4–2.0 g protein/kg body weight/day (g/kg/d) is sufficient for most exercising individuals, a value that falls in line within the Acceptable Macronutrient Distribution Range published by the Institute of Medicine for protein.Higher protein intakes (2.3–3.1 g/kg/d) may be needed to maximize the retention of lean body mass in resistance-trained subjects during hypocaloric periods.There is novel evidence that suggests higher protein intakes (>3.0 g/kg/d) may have positive effects on body composition in resistance-trained individuals (i.e., promote loss of fat mass).Recommendations regarding the optimal protein intake per serving for athletes to maximize MPS are mixed and are dependent upon age and recent resistance exercise stimuli. General recommendations are 0.25 g of a high-quality protein per kg of body weight, or an absolute dose of 20–40 g.Acute protein doses should strive to contain 700–3000 mg of leucine and/or a higher relative leucine content, in addition to a balanced array of the essential amino acids (EAAs).These protein doses should ideally be evenly distributed, every 3–4 h, across the day.The optimal time period during which to ingest protein is likely a matter of individual tolerance, since benefits are derived from pre- or post-workout ingestion; however, the anabolic effect of exercise is long-lasting (at least 24 h), but likely diminishes with increasing time post-exercise.While it is possible for physically active individuals to obtain their daily protein requirements through the consumption of whole foods, supplementation is a practical way of ensuring intake of adequate protein quality and quantity, while minimizing caloric intake, particularly for athletes who typically complete high volumes of training. Rapidly digested proteins that contain high proportions of essential amino acids (EAAs) and adequate leucine, are most effective in stimulating MPS. Different types and quality of protein can affect amino acid bioavailability following protein supplementation. Athletes should consider focusing on whole food sources of protein that contain all of the EAAs (i.e., it is the EAAs that are required to stimulate MPS). Endurance athletes should focus on achieving adequate carbohydrate intake to promote optimal performance; the addition of protein may help to offset muscle damage and promote recovery. Pre-sleep casein protein intake (30–40 g) provides increases in overnight MPS and metabolic rate without influencing lipolysis.

Purpose The purpose of this study was to compare the physiological responses of a high-volume (HV; 8 sets of 10 repetitions) versus high-intensity (HI; 8 sets of 3 repetitions) exercise protocol in resistance-trained men. Methods Twelve men (24.5 ± 4.2 years; 82.3 ± 8.4 kg; 175.2 ± 5.5 cm) with 6.3 ± 3.4 years of resistance training experience performed each protocol in a counterbalanced, randomized order. Performance [counter movement jump peak power (CMJP), isokinetic (ISOK) and isometric leg extension (MVIC), isometric mid-thigh pull (IMTP), and isometric squat (ISQ)] and muscle morphological [cross-sectional area (CSA) of vastus lateralis] assessments were performed at baseline (BL), 30-min (P-30 min), 24-h (P-24 h), 48-h (P-48 h), and 72-h (P-72 h) post-exercise for each testing session. In addition, endocrine (testosterone and cortisol), inflammatory [interleukin-6 (IL-6) and C-reactive protein (CRP)], and markers of muscle damage [creatine kinase (CK), lactate dehydrogenase (LDH), and myoglobin (Mb)] were assessed at the same time points. Results Significantly greater reductions in CMJP (p

The purpose of this study was to examine the effect of β-alanine (BA) ingestion on tissue carnosine levels and the impact such changes would have on combat specific activity. Eighteen soldiers (19.9 ± 0.8 year) from an elite combat unit were randomly assigned to either a BA or placebo (PL) group. Before and following a 30-day supplementation period carnosine content of the gastrocnemius muscle and brain was determined by proton magnetic resonance spectroscopy. During each testing session, participants performed military relevant tasks that included a 2.5 km run, a 1-min sprint, 50-m casualty carry, repeated 30-m sprints with target shooting, and a 2-min serial subtraction test (SST) to assess cognitive function under stressful conditions. A significant elevation (p = 0.048) in muscle carnosine content was noted in BA compared to PL. Changes in muscle carnosine content was correlated to changes in fatigue rate (r = 0.633, p = 0.06). No changes (p = 0.607) were observed in brain carnosine content. Following supplementation, no differences were noted in 2.5 km run, 1-min sprint, repeated sprint, or marksmanship performance, but participants in BA significantly (p = 0.044) improved their time for the 50-m casualty carry and increased their performance (p = 0.022) in the SST compared to PL. In summary, 30-days of BA ingestion can increase muscle carnosine content and improve aspects of military specific performance. Although cognitive performance was significantly greater in participants consuming BA compared to placebo, current study methods were unable to detect any change in brain carnosine levels, thus, the precise mechanism underlying these effects remains elusive.

To determine if unilateral measures of muscle architecture in the rectus femoris (RF) and vastus lateralis (VL) were related to (and predictive of) sprinting speed and unilateral (and bilateral) force (FRC) and power (POW) during a 30 s maximal sprint on the Woodway Curve 3.0 non-motorized treadmill. Twenty-eight healthy, physically active men (n = 14) and women (n = 14) (age = 22.9 ± 2.4 years; body mass = 77.1 ± 16.2 kg; height = 171.6 ± 11.2 cm; body-fa t = 19.4 ± 8.1%) completed one familiarization and one 30-s maximal sprint on the TM to obtain maximal sprinting speed, POW and FRC. Muscle thickness (MT), cross-sectional area (CSA) and echo intensity (ECHO) of the RF and VL in the dominant (DOM; determined by unilateral sprinting power) and non-dominant (ND) legs were measured via ultrasound. Pearson correlations indicated several significant (p < 0.05) relationships between sprinting performance [POW (peak, DOM and ND), FRC (peak, DOM, ND) and sprinting time] and muscle architecture. Stepwise regression indicated that POW(DOM) was predictive of ipsilateral RF (MT and CSA) and VL (CSA and ECHO), while POW(ND) was predictive of ipsilateral RF (MT and CSA) and VL (CSA); sprinting power/force asymmetry was not predictive of architecture asymmetry. Sprinting time was best predicted by peak power and peak force, though muscle quality (ECHO) and the bilateral percent difference in VL (CSA) were strong architectural predictors. Muscle architecture is related to (and predictive of) TM sprinting performance, while unilateral POW is predictive of ipsilateral architecture. However, the extent to which architecture and other factors (i.e. neuromuscular control and sprinting technique) affect TM performance remains unknown.

The purpose of this study was to examine the effect of the L-Alanyl-L-Glutamine dipeptide (AG) on cognitive function and reaction time (RT) following endurance exercise. Twelve male endurance athletes (23.5 ± 3.7 y; 175.5 ± 5.4 cm; 70.7 ± 7.6 kg) performed four trials, each consisting of running on a treadmill at 70% of VO2max for 1h, then at 90% of VO2max until exhaustion. One trial consisted of no hydration (DHY), another required ingestion of only a sports electrolyte drink (ED) and two trials required ingestion of a low dose (LD; 300 mg·500 ml(-1)) and high dose (HD) of AG (1 g·500ml(-1)) added to the ED. Cognitive function and reaction tests were administered pre- and post-exercise. Magnitude based inferences were used to analyze ∆ cognitive function and ∆ reaction test data. Results indicated that DHY had a possible negative effect on number of hits in a 60-sec reaction test compared to LD and HD, while ED appeared to have a negative effect compared to HD. Analysis of lower body quickness indicated that LD and HD were likely improved in comparison to DHY. Performance on the serial subtraction test appeared to be possibly better in ED than DHY, while other comparisons between groups regarding cognitive function were unclear. In conclusion, rehydrating with AG during submaximal exercise may maintain or enhance subsequent RT in upper and lower body activities compared to DHY. These same effects were not apparent when participants consumed ED.

ADAM J. WELLS, MS, DAVID H. FUKUDA, PhD, JAY R. HOFFMAN, PhD, ADAM M. GONZALEZ, MEd,ADAM R. JAJTNER, MS, JEREMY R. TOWNSEND, MS, GERALD T. MANGINE, MEd, MAREN S. FRAGALA, PhD, andJEFFREY R. STOUT, PhDInstitute of Exercise Physiology and Wellness, University of Central Florida (UCF), 4000 Central Florida Blvd Orlando, Florida, 32816,USAAccepted 21 February 2014ABSTRACT: Introduction: Variations in transverse point of mea-sure on the vastus lateralis (VL) may significantly affect therelationship between structure and function. The purpose of thisstudy was to compare changes in muscle architecture at 2commonly used points of measure (VL0 and VL5). Methods:Maximal strength (1-repetition maximum [1RM] barbell squat)and muscle architecture were assessed PRE and POST 15weeks of periodized resistance training. VL0 was 50% of thestraight line distance between the greater trochanter and lateralepicondyle of the femur. VL5 was 5cm medial to VL0. Results:Increases in 1RM strength (3.762.4 kg; P50.004) wereobserved. Changes in muscle thickness (MT) at VL5 were sig-nificantly greater than at VL0 (P50.006). Changes in strengthcorrelated with changes in muscle architecture at VL0 only (MT:r50.561; fascicle length: r50.503). Conclusions: Changes inmuscle architecture appear to occur in a non-homogeneousmanner.

The purpose of this randomized, cross-over design study was to examine the effect of three different muscle potentiation protocols on acute changes in muscle architecture and vertical jump performance. Eleven experienced, resistance trained men (25.2±3.6y) completed three potentiation squat protocols using moderate intensity (MI; 75%, 3 sets x 10 repetitions), high intensity (HI; 90%, 3 sets x 3 repetitions) and 100% (1RM; 1 set x 1repetition) of their 1RM. In addition, all participants completed a control session (CTL) in which no protocol was performed. During each testing session, muscle architecture and vertical jump testing were assessed at baseline (BL), 8min post (8P) and 20min post (20P) workout. Ultrasound measures included cross sectional area (CSA) and pennation angle (PANG) of both the rectus femoris (RF) and vastus lateralis (VL). Following each ultrasound measure, peak vertical jump power (PVJP) and mean (MVJP) power was assessed using an accelerometer. Magnitude based inferences were used to make comparisons between trials. The MI trial resulted in a likely greater increase from BL to 8P and 20P in RF-CSA and VL-CSA, while the HI trial resulted in a likely greater change from BL to 20P in both RF-CSA and VL-CSA. Meanwhile, changes in PVJP and MVJP for the MI trial was likely decreased at BL-8P and BL–20P, while the HI trial was shown to result in a likely or possible decrease compared to CTL at BL-8P and BL–20P, respectively. A likely negative relationship was observed between changes in VL-PANG and MVJP (r = -0.35; p , 0.018) at BL-8P, and between changes in PVJP and RF-CSA (r = -0.37; p , 0.014) at BL–20P. Results of this study were unable to demonstrate any potentiation response from the trials employed, however these protocols did result in acute muscle architectural changes.

The purpose of this study was to determine the relationship between visual tracking speed (VTS) and reaction time (RT) on basketball-specific measures of performance. Twelve professional basketball players were tested before the 2012-13 season. Visual tracking speed was obtained from 1 core session (20 trials) of the multiple object tracking test, whereas RT was measured by fixed- and variable-region choice reaction tests, using a light-based testing device. Performance in VTS and RT was compared with basketball-specific measures of performance (assists [AST]; turnovers [TO]; assist-to-turnover ratio [AST/TO]; steals [STL]) during the regular basketball season. All performance measures were reported per 100 minutes played. Performance differences between backcourt (guards; n = 5) and frontcourt (forward/centers; n = 7) positions were also examined. Relationships were most likely present between VTS and AST (r = 0.78; p < 0.003), STL (r = 0.77; p < 0.003), and AST/TO (r = 0.78; p < 0.003), whereas a likely relationship was also observed with TO (r = 0.49; p < 0.109). Reaction time was not related to any of the basketball-specific performance measures. Backcourt players were most likely to outperform frontcourt players in AST and very likely to do so for VTS, TO, and AST/TO. In conclusion, VTS seems to be related to a basketball player's ability to see and respond to various stimuli on the basketball court that results in more positive plays as reflected by greater number of AST and STL and lower turnovers.

The relationship between PWCFT and common measures used to assess sarcopenia in older adults were examined. Fifty-eight older adults [age: 71.1 ± 6.2 years; body mass index (BMI): 28.0 ± 5.4 kg/m2] completed the testing procedures. Sarcopenia-related body composition was measured by dual-energy X-ray absorptiometry and participants performed a discontinuous cycle ergometry test to determine PWCFT. Functionality assessments included maximal isometric grip strength (GRIP) and sit-to-stand (STS) repetitions in 30 s. Muscle quality (MQ) was defined as GRIP relative to appendicular lean soft tissue (ALM), while skeletal muscle index (SMI) was defined as ALM/height2. Pearson correlations were used to examine the relationships among dependent variables. PWCFT showed significant relationships with ALM (r = 0.57), SMI (r = 0.47), body fat percentage (BF%) (r = −0.50), GRIP (r = 0.49), and STS (r = 0.44). For follow-up analyses, study participants were categorized into low sarcopenia risk (n = 31) or high sarcopenia risk (n = 27) groups by SMI. Sarcopenia risk was associated with PWCFT [odds ratio (OR): 1.051, 95% confidence interval (CI): 1.016–1.087] and STS (OR: 1.305, CI: 1.060–1.607), but not GRIP (OR: 1.098, CI: 0.989–1.218). Using receiver–operator characteristic curve analysis, both PWCFT [area under the curve (AUC): 0.737, CI: 0.608–0.866, optimal cutoff: 37.5 W] and STS (AUC: 0.749, CI: 0.623–0.874, optimal cutoff: 12.5 repetitions) showed discriminative ability with regard to sarcopenia risk. The current data suggest that the neuromuscular fatigue threshold, as measured by PWCFT, is related to measures of body composition and function in older adults.

Exercise routines in which intensity fluctuates, such as Spinning and Treading, are gaining in popularity in fitness industry. However, literature on how this dynamic protocol may affect the exercise metabolism is lacking. The present investigation was undertaken to examine the effect of intensity fluctuation and its magnitude on oxygen uptake and substrate utilization during exercise and recovery. Fifteen men and 15 women were randomly assigned into 1 of the 3 groups consisting of 10 participants of equal gender. Each group performed one of the three 30-minute exercise protocols that yielded the same total power output: (a) cycling at a constant power output of 75 W (P1), (b) cycling with power output alternating between 50 and 100 W every 5 minutes (P2), and (c) cycling with power output alternating between 25 and 125 W every 5 minutes (P3). Each exercise session was followed by a 25-minute recovery. Oxygen uptake (VO2), carbon dioxide production (VCO2), and respiratory exchanged ratio were measured at rest and during exercise and recovery. Rates of carbohydrate (COX) and fat oxidation (FOX) were calculated based on VO2 and VCO2 using the stoichiometric equations. VO2 in ml·kg-1·min-1 did not differ across the 3 protocols during exercise, but was higher (p ≤ 0.05) in P2 (4.92 ± 0.51) or P3 (4.94 ± 0.24) than P1 (4.17 ± 0.19) during recovery. COX in mg·kg-1·min-1 was higher (p ≤ 0.05) in P3 (17.68 ± 1.30) than in P1 (12.22 ± 1.55) or P2 (12.06 ± 1.47) during exercise and higher in P3 (4.17 ± 0.45) than in P1 (2.60 ± 0.36) during recovery. FOX in mg·kg-1·min-1 was lower (p ≤ 0.05) in P3 (2.61 ± 0.47) than in P1 (4.30 ± 0.60) or P2 (4.22 ± 0.47) during exercise but remained similar across the 3 protocols during recovery. These data indicate that intensity fluctuation of sufficient magnitude can alter exercise metabolism independent of the total power output or overall intensity. The 2 variable intensity protocols used in the study (i.e., P2 and P3) are equally effective in augmenting postexercise V[Combining Dot Above]O2, but the protocol with a greater magnitude of fluctuation also elicits greater COX coupled with reduced FOX during exercise.

Introduction Sarcopenia is currently best described as an age-related decline in skeletal muscle mass and function. However, no consensus exists as to how to best quantify muscle function in older adults. The muscle quality index (MQI) was recently recommended as an ideal evidence-based assessment of functional status in older adults. Nevertheless, the usefulness of MQI to assess physical function is limited by whether it is reflective of muscle qualitative changes to an intervention. Thus, the purpose of this investigation was to determine whether MQI changes in response to resistance exercise training and detraining and how such changes correspond to other recommended measures of physical function proposed by suggested definitions of sarcopenia. Methods Twenty-five older adults (70.6 ± 6.1 y; BMI = 28.1 ± 5.4 kg · m− 2) completed a 6-week resistance training program in a wait-list controlled, cross-over design. MQI was determined as power output from timed sit to stand (STS), body mass, and leg length. Gait speed, hand grip strength, get-up-and-go and lean body mass (LBM) were evaluated before and after exercise training and detraining. MQI and functional changes to training and detraining were evaluated with repeated measures ANOVA and clinical interpretations of magnitude based inferences. Results Short term resistance training significantly and clinically improved MQI (203.4 ± 64.31 to 244.3 ± 82.92 W), gait time (1.85 ± 0.36 to 1.66 ± 0.27 s) and sit to stand performance (13.21 ± 2.51 to 11.05 ± 1.58 s). Changes in LBM and hand grip strength were not significant or clinically meaningful. De-training for 6-weeks did not result in significant changes in any measure from post-training performance.

The purpose of this investigation was to determine which physiological assessments best predicted high-intensity running (HIR) performance during a women's collegiate soccer game. A secondary purpose was to examine the relationships among physiological performance measures including muscle architecture on soccer performance (distance covered, HIR, and sprints during the game) during a competitive collegiate women's soccer game. Ten National Collegiate Athletic Association (NCAA) Division I women soccer players performed physiological assessments within a 2-week period before a competitive regulation soccer game performed during the spring season. Testing consisted of height, body mass, ultrasound measurement of dominant (DOMleg), and nondominant leg (NDOMleg) vastus lateralis for muscle thickness (MT) and pennation angle (PA), VO2max, running economy, and Wingate anaerobic test (WAnT) for peak power (PP), mean power (MP), and fatigue rate (FR). During the game, distance run, HIR, and sprints were measured using a 10-Hz global positioning system. Stepwise regression revealed that VO2max, dominant leg thickness, and dominant leg PA were the strongest predictors of HIR distance during the game (R = 0.989, SEE = 115.5 m, p = 0.001). V[Combining Dot Above]O2max was significantly correlated with total distance run (r = 0.831; p = 0.003), HIR (r = 0.755; p = 0.012), WAnTPP (r = -0.737; p = 0.015), WAnTPP·kg (r = -0.706; p = 0.022), and WAnTFR (r = -0.713; p = 0.021). DOMlegMT was significantly correlated with WAnTFR (r = 0.893; p = 0.001). DOMlegPA was significantly correlated with WAnTFR (r = 0.740; p = 0.023). The NDOMlegPA was significantly correlated to peak running velocity (r = 0.781; p = 0.013) and WAnT MP·kg (r = 0.801; p = 0.01). Results of this study indicate that V[Combining Dot Above]O2max and muscle architecture are important characteristics of NCAA Division I women soccer players and may predict HIR distance during a competitive contest.

The inflammatory response to muscle-damaging exercise requires monocyte mobilization and adhesion. Complement receptor type 3 (CR3) and macrophage inflammatory protein (MIP)-1β enables monocyte recruitment, adhesion, and subsequent infiltration into damaged muscle tissue. The purpose of this study was to examine the effects of cold water immersion (CWI) and/or β-hydroxy-β-methylbutyrate free acid (HMB-FA) on CR3 expression and MIP-1β concentration after four sets of up to 10 repetitions of squat, dead lift, and split squat exercises at 70–80% 1-repetition maximum. Thirty-nine resistance-trained men (22.2 ± 2.5 yr) were randomly divided into four groups: 1) placebo (PL), 2) HMB-FA, 3) HMB-FA-CWI, and 4) PL-CWI. The HMB-FA groups ingested 3 g/day, and CWI groups were submersed into 10–12°C water for 10 min after exercise. Blood was sampled at baseline (PRE), immediately post- (IP), 30 min post- (30P), 24 h post- (24P), and 48 h post (48P)-exercise. Circulating MIP-1β was assayed and CR3 expression on CD14+ monocytes was measured by flow cytometry. Without treatment, CR3 expression significantly elevated at 30P compared with other time points ( P = 0.030–0.047). HMB-FA significantly elevated the percentage of monocytes expressing CR3 between IP and 24P ( P = 0.046) and between IP and 48P ( P = 0.046). No time effect was observed for MIP-1β concentration. The recovery modalities showed to attenuate the rise in CR3 following exercise. Additionally, supplementation with HMB-FA significantly elevated the percentage of monocytes expressing CR3 during recovery. Although the time course that inflammatory responses are most beneficial remains to be determined, recovery modalities may alter immune cell mobilization and adhesion mechanisms during tissue recovery.

Bartolomei, S, Hoffman, JR,Merni, F, and Stout, JR. A comparison of traditional and block periodized strength training programs in trained athletes. J Strength Cond Res 28(4): 990–997, 2014— The purpose of this study was to compare 2 different periodization models in strength and power athletes. Twenty-four experienced resistance trained men were randomly assigned to either a block periodization training program (BP; age = 24.2 6 3.1 years, body mass = 78.5 6 11.0 kg, height = 177.6 6 4.9 cm) or to a traditional periodization program (TP; age = 26.2 6 6.0 years, body mass = 80.5 6 13.3 kg, height = 179.2 6 4.6). Participants in both training programs performed 4 training sessions per week. Each training program consisted of the same exercises and same volume of training (total resistance lifted per session). The difference between the groups was in the manipulation of training intensity within each training phase. Strength and power testing occurred before training (PRE) and after 15 weeks (POST) of training. Magnitude-based inferences were used to compare strength and power performance between the groups. Participants in BP were more likely (79.8%) to increase the area under the force-power curve than TP. Participants in BP also demonstrated a likely positive (92.76%) decrease in the load corresponding to maximal power at the bench press compared with TP group, and a possible improvement (;60%) in maximal strength and power in the bench press. No significant changes were noted between groups in lower-body strength or jump power performance after the 15-week training period. Results of this study indicate that BP may enhance upper-body power expression to a greater extent than TP with equal volume; however, no differences were detected for lower-body performance and body composition measures.

Recently, the Dynavision™ D2 Visuomotor Training Device (D2) has emerged as a tool in the assessment of reaction time (RT); however, information regarding the reliability of the D2 have been limited, and to date, reliability data have been limited to non- generalizable samples. Therefore, the purpose of this study was to establish intraclass correlation coefficients (ICC2,1) for the D2 that are generalizable across a population of recreationally active young adults. Forty-two recreationally active men and women (age: 23.41 ± 4.84 years; height: 1.72 ± 0.11 m; mass: 76.62 ± 18.26 Kg) completed 6 trials for three RT tasks of increasing complexity. Each trial was separated by at least 48-hours. A repeated measures ANOVA was used to detect differences in performance across the six trials. Intraclass correlation coefficients (ICC2,1) standard error of measurement (SEM), and minimal differences (MD) were used to determine the reliability of the D2 from the two sessions with the least significant difference score. Moderate to strong reliability was demonstrated for visual RT (ICC2,1: 0.84, SEM: 0.033), and reactive ability in both Mode A and Mode B tasks (Mode A hits: ICC2,1: 0.75, SEM: 5.44; Mode B hits: ICC2,1: 0.73, SEM: 8.57). Motor RT (ICC2,1: 0.63, SEM: 0.035s) showed fair reliability, while average RT per hit for Modes A and B showed moderate reliability (ICC2,1: 0.68, SEM: 0.43 s and ICC2,1: 0.72, SEM: 0.03 s respectively). It appears that one familiarization trial is necessary for the choice reaction time (CRT) task while three familiarization trials are necessary for reactive RT tasks. In conclusion, results indicate that the Dynavision™ D2 is a reliable device to assess neuromuscular reactivity given that an adequate practice is provided. The data presented are generalizable to a population of recreationally active young adults.

Introduction: Muscle morphology and architecture changes in response to 6 weeks of progressive resistance train- ing were examined in healthy older adults. Methods: In this randomized, controlled design, muscle strength, quality, and architecture were evaluated with knee extension, DEXA, and ultrasound, respectively, in 25 older adults. Results: Resistance training resulted in significant increases in strength and muscle quality of 32% and 31%, respectively. Cross-sectional area of the vastus lateralis increased by 7.4% (p � 0.05). Physiological cross-sectional area (PCSA) of the thigh, a composite measure of muscle architecture, was related significantly to strength (r 50.57; p � 0.01) and demonstrated a significant interaction after training (p � 0.05). Change in PCSA of the vastus lateralis was associated with change in strength independent of any other measure. Conclusions: Six weeks of resistance training was effective at increasing strength, muscle quality, and muscle morphology in older adult men and women. Muscle Nerve 49:584-592, 2014

Background N-terminal peptide of procollagen type III (P3NP) and C-terminal agrin fragment (CAF) are circulating biomarkers that are related to lean body mass in older adults. P3NP is a circulating marker reflective of muscular structural remodeling while CAF is a circulating marker of neuromuscular remodeling. As resistance exercise is an established intervention that can effectively improve muscle quality, we sought to evaluate circulating biomarker changes corresponding to a resistance exercise intervention in older adults. Methods Twenty-three older adults (aged 61 to 85 years) were randomized into an intervention (6-week resistance training) or control group. Resting circulating P3NP, CAF, lean body mass (LBM), muscle cross-sectional area (CSA), muscle strength, and muscle quality were determined at baseline and after the intervention or control period by enzyme-linked immunosorbent assay, dual-energy X-ray absorptiometry, ultrasound, leg extension, and relative strength, respectively. Changes in circulating biomarkers and measures of muscle mass and quality were evaluated with repeated-measures analysis of variance; clinical interpretations were made with magnitude-based inferences, and relationships between variables were evaluated with bivariate correlations. Results The short-term resistance exercise intervention was effective at improving muscle quality by 28 % (p

The purpose of this study was to examine the effect of β-hydroxy-β-methylbutyrate-free acid (HMB-FA) and cold-water immersion (CWI) on circulating concentrations of TNF-α and monocyte TNF-α receptor 1 (TNFR1) expression. Forty resistance-trained men (22.3 ± 2.4 yr) were randomized into four groups [placebo (PL), HMB-FA, CWI, and HMB-FA-CWI] and performed an acute, intense exercise protocol (four sets of up to 10 repetitions of the squat, dead lift, and split squat). Participants also performed four sets of up to 10 repetitions of the squat at 24 and 48 h following the initial exercise bout. Blood was sampled before exercise (PRE), immediately postexercise (IP), and 30 min, 24 h, and 48 h postexercise (30P, 24P, and 48P, respectively). Circulating TNF-α was assayed, and TNFR1 expression on CD14+ monocytes was measured by flow cytometry. The exercise protocol significantly elevated TNF-α in only PL ( P = 0.006) and CWI ( P = 0.045) IP. Mean percent changes show that TNF-α significantly increased from PRE to IP for only PL and CWI groups ( P < 0.05), whereas the percent change of TNF-α for HMB-FA and HMB-FA-CWI was not significant. TNFR1 expression was elevated in PL ( P = 0.023) and CWI ( P = 0.02) at 30P compared with PRE, whereas both HMB-FA-treated groups did not increase significantly. In conclusion, HMB-FA attenuated circulating TNF-α IP and TNFR1 expression during recovery compared with PL and CWI. HMB-FA supplementation may attenuate the initial immune response to intense exercise, which may reduce recovery time following intense exercise.

The purpose of this study was to compare starters (S) with nonstarters (NS), on their ability to maintain strength, power, and quickness during a competitive National Basketball Association (NBA) season. Twelve NBA players were assessed at the beginning and end of the competitive season. However, because of trades and injury, only 7 (S = 4, NS = 3) players (28.2 ± 3.4 years; 200.9 ± 9.4 cm; 104.7 ± 13.9 kg; 7.2 ± 1.9% body fat) participated in both testing sessions and underwent analysis. Anthropometric performance (repetitive vertical jump power [VJP], squat power [SQT power], and reaction time) and subjective feelings of energy, focus, alertness, and fatigue were recorded during each testing session. Results were interpreted using magnitude-based statistics to make inferences on true differences between starters and nonstarters using the unequal variances t-statistic. Starters played an average of 27.8 ± 6.9 minutes per game and nonstarters played an average of 11.3 ± 7.0 minutes per game. During the course of the season, changes in VJP indicated that starters were likely to increase VJP ([INCREMENT] = 77.3 ± 78.1 W) compared to nonstarters ([INCREMENT] = -160.0 ± 151.0 W). There also appeared to be a possible beneficial effect on maintaining reaction time in starters ([INCREMENT] = 0.005 ± 0.074 seconds) compared with nonstarters ([INCREMENT] = 0.047 ± 0.073 seconds). In addition, no clear differences in [DELTA]SQT power were seen between starters ([INCREMENT] = 110.8 ± 141.4 W) and nonstarters ([INCREMENT] = 143.5 ± 24.7 W). Changes in subjective feelings of energy indicated that starters were very likely to maintain their energy over the course of a season. It also appeared possible that starters were able to have a more positive response to subjective measures of fatigue and alertness than nonstarters, with only trivial differences between starters and nonstarters in regards to maintaining focus. Results of this study suggest that NBA players may enhance lower-body power, repetitive jump ability, and reaction during a competitive season, which appear to be enhanced with the stimulus of playing time.

The purpose of this study was to investigate age-related changes in anthropometric and performance variables in professional baseball players. Baseball players (n = 1,157) from several professional baseball organizations were categorized into 7 cohorts based upon age. All adolescent athletes were categorized as age group 1 (AG1), whereas the next 5 groups (AG2-AG6) consisted of players 20-22, 23-25, 26-28, 29-31, and 31-34 years, respectively. The final group (AG7) comprised athletes ≥35 years. All performance assessments were part of the athlete's normal preseason training camp testing routine. Field assessments were used to analyze lower-body power, speed, agility, grip strength, and body composition. The players were heaviest between the ages of 29 and 31 (AG5), and their body mass in that age group was 10.1% (p = 0.004) greater than that of AG1. A 7.0% increase (p = 0.000) in lean body mass occurred between AG1 and AG5. No differences in 10-yd sprint times or agility were seen across any age group or position. A 2.0 seconds (p = 0.001) slower run time for the 300-yd shuttle was seen between AG4 and AG5 for all positions combined. Elevations in grip strength were seen at AG4 compared with AG1 (p = 0.001) and AG2 (p = 0.007) for all positions combined. No other differences were noted. Lower-body power was increased for all positions combined from AG1 to AG3 (p = 0.007). This pattern was similar to that observed in position players, but a 12.4% decrease (p = 0.024) in VJMP was seen between AG7 and AG5 in pitchers. Results of this study indicate that lower-body power is maintained in baseball players until the age of 29-31, whereas speed, agility, and grip strength are maintained in players able to play past the age of 35 years. Age-related differences observed in this study suggest that athletes focus on their strength and conditioning programs to extend the length of their professional careers.

Mangine, GT, Hoffman, JR, Gonzalez, AM, Townsend, JR, Wells, AJ, Jajtner, AR, Beyer, KS, Boone, CH, Wang, R, Miramonti, AA, LaMonica, MB, Fukuda, DH, Witta, EL, Ratamess, NA, and Stout, JR. Exercise-induced hormone elevations are related to muscle growth. J Strength Cond Res 31(1): 45-53, 2017-Partial least squares regression structural equation modeling (PLS-SEM) was used to examine relationships between the endocrine response to resistance exercise and muscle hypertrophy in resistance-trained men. Pretesting (PRE) measures of muscle size (thickness and cross-sectional area) of the vastus lateralis and rectus femoris were collected in 26 resistance-trained men. Participants were randomly selected to complete a high-volume (VOL, n = 13, 10-12RM, 1-minute rest) or high-intensity (INT, n = 13, 3-5RM, 3-minute rest) resistance training program. Blood samples were collected at baseline, immediately postexercise, 30-minute, and 60-minute postexercise during weeks 1 (week 1) and 8 (week 8) of training. The hormonal responses (testosterone, growth hormone [22 kD], insulin-like growth factor-1, cortisol, and insulin) to each training session were evaluated using area-under-the-curve (AUC) analyses. Relationships between muscle size (PRE), AUC values (week 1 + week 8) for each hormone, and muscle size (POST) were assessed using a consistent PLS-SEM algorithm and tested for statistical significance (p ≤ 0.05) using a 1,000 samples consistent bootstrapping analysis. Group-wise comparisons for each relationship were assessed through independent t-tests. The model explained 73.4% (p < 0.001) of variance in muscle size at POST. Significant pathways between testosterone and muscle size at PRE (p = 0.043) and muscle size at POST (p = 0.032) were observed. The ability to explain muscle size at POST improved when the model was analyzed by group (INT: R = 0.882; VOL: R = 0.987; p < 0.001). No group differences in modal quality were found. Exercise-induced testosterone elevations, independent of the training programs used in this study, seem to be related to muscle growth.

The purpose of this study was to compare the coadministration of the probiotic

Resistance exercise increases muscle mass by shifting protein balance in favor of protein accretion. Androgens independently alter protein balance, but it is unknown whether androgens alter this measure after resistance exercise. To answer this, male mice were subjected to sham or castration surgery 7–8 wk before undergoing a bout of unilateral, high-frequency, electrically induced muscle contractions in the fasted or refed state. Puromycin was injected 30 min before euthanasia to measure protein synthesis. The tibialis anterior was analyzed 4 h postcontraction. In fasted mice, neither basal nor stimulated rates of protein synthesis were affected by castration despite lower phosphorylation of mechanistic target of rapamycin in complex 1 (mTORC1) substrates [p70S6K1 (Thr389) and 4E-BP1 (Ser65)]. Markers of autophagy (LC3 II/I ratio and p62 protein content) were elevated by castration, and these measures remained elevated above sham values after contractions. Furthermore, in fasted mice, the protein content of Regulated in Development and DNA Damage 1 (REDD1) was correlated with LC3 II/I in noncontracted muscle, whereas phosphorylation of uncoordinated like kinase 1 (ULK1) (Ser757) was correlated with LC3 II/I in the contracted muscle. When mice were refed before contractions, protein synthesis and mTORC1 signaling were not affected by castration in either the noncontracted or contracted muscle. Conversely, markers of autophagy remained elevated in the muscles of refed, castrated mice even after contractions. These data suggest the castration-mediated elevation in baseline autophagy reduces the absolute positive shift in protein balance after muscle contractions in the refed or fasted states. NEW & NOTEWORTHY In the absence of androgens, markers of autophagy were elevated, and these could not be normalized by muscle contractions. In the fasted state, REDD1 was identified as a potential contributor to autophagy in noncontracted muscle, whereas phosphorylation of ULK1 may contribute to this process in the contracted muscle. In the refed state, markers of autophagy remain elevated in both noncontracted and contracted muscles, but the relationship with REDD1 and ULK1 (Ser757) no longer existed.