Mediators of monocyte migration, complement receptor-3 (CR3), and chemokine ligand-4 (CCL4) were measured in response to recovery modalities following resistance exercise. Thirty resistance-trained men (23.1±2.9 y;175.2±7.1 cm;82.1±8.4 kg) were given neuromuscular electric stimulation (NMES), cold water immersion (CWI), or control (CON) treatments immediately following resistance exercise. Blood samples were obtained preexercise (PRE), immediately (IP), 30 minutes (30 P), 24 hours (24 H), and 48 hours (48 H) after exercise for measurement of circulating CCL4 and CR3 expression on CD14+ monocytes, by assay and flow cytometry. Circulating CCL4 showed no consistent changes. Inferential analysis indicated that CR3 expression was likely greater in CON at 30 P than NMES (90.0%) or CWI (86.8%). NMES was likely lower than CON at 24 H (92.9%) and very likely lower at 48 H (98.7%). Expression of CR3 following CWI was very likely greater than CON (96.5%) at 24 H. The proportion of CR3+ monocytes was likely greater following CWI than NMES (85.8%) or CON (85.2%) at 24 H. The change in proportion of CR3+ monocytes was likely (86.4%) greater following NMES than CON from IP to 30 P. The increased expression of CR3 and increased proportion of CR3+ monocytes following CWI at 24 H indicate a potentially improved ability for monocyte adhesion to the endothelium, possibly improving phagocytosis of damaged tissues.
The coronavirus disease-2019 (COVID-19) pandemic is having a widespread impact on societies across the globe. As part of the effort to control transmission in the United States, many businesses either closed or instituted nonpharmaceutical control measures and allowed only essential workers on-site. During summer and fall of 2020, employers began formulating "return to work" strategies designed to mitigate the risk of transmission among employees. On a population level, several countries implemented national testing and surveillance strategies that proved effective in mitigating citizen-to-citizen transmission and contributed to suppressing COVID-19. A crucial component of many such strategies is population-based testing to identify and engage individuals with asymptomatic or presymptomatic infection, which also is relevant to return-to-work strategies. The authors describe an approach that multisite employers might use to help mitigate transmission of COVID-19 in the workplace. This approach leverages a bioinformatics platform informed by real-time PCR test data at the county and subcounty (eg, Public Use Microdata Area) level, allowing for population-based testing to be selectively targeted for employees in geographies with elevated SARS-CoV-2 positivity. A "Command Center" application integrates data from multiple sources (eg, local infection trends, employee symptom diaries, Bluetooth thermometers) in real time, which can be used to inform decisions regarding surveillance and employee self-isolation or quarantine; a mobile phone-based application provides for rapid, secure communication with employees. This overview is based on peer-reviewed literature and the early experience of a large employer with implementing bioinformatics tools to mitigate the impact of the pandemic on the workplace.
Mangine, GT, Hoffman, JR, Wells, AJ, Gonzalez, AM, Rogowski, JP, Townsend, JR, Jajtner, AR, Beyer, KS, Bohner, JD, Pruna, GJ, Fragala, MS, and Stout, JR. Visual tracking speed is related to basketball-specific measures of performance in NBA players. J Strength Cond Res 28(9): 2406–2414, 2014—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 purpose of this investigation was to characterize upper body concentric and eccentric strength performance in men and women. 24 men (22.9 yrs+2.8;177.9+18.2 cm; 82.2+7.1 kg) and 23 women (21.5 yrs+2.5;164.5+15.4 cm; 65.3+10.3 kg) gave written informed consent to participate in the study. A Dyformon /ABLE II (D/AII)instrument (Exerbotics, LLC, McPhearson, KS) monitored three coordinating subsystems: the electromechanical impingement exerciser, the force and position monitoring sensors, and the computer control and recording system was used to record data. Maximal concentric peak force and position of peak force were collected at three different velocities (0.10 m.s-1; 0.20 m.s-1;0.28 m.s-1). Test retest reliability demonstrated ICC of Rs>0.92. Significant correlations (r's from 0.78 to 0.95) were observed between the 1 RM bench press (Plyometric Power System, Lismore Australia [smith machine]) and the D/AII instrument for various peak forces indicating a high similarity between the measures. Men demonstrated significantly (p < 0.05) higher forces in peak forces in absolute terms (e.g. CON, Men: 0.10 m.s-1=1300.4+294; 0.20 m.s-1 = 1272.6+302 0.28 m.s-1=1157.9+281; Women: 0.10 m.s-1=712.76+164;0.20 m.s-1 =671.5+186; 0.28 m.s-1 =573.25+143) but the same response were see when corrected relative to body mass, and relative to fat free mass. While the ECC/CON force ratio has been shown to be higher in women in prior studies of single joint movements, we showed no differences between men and women at any of the test velocities in the bench press. Significant differences between genders in the concentric position of peak force were seen at 0.28 m.s-1and 0.20 m.s-1 testing velocities. The occurrence of the position of peak force near the top of the range of motion along with slower women's rate of force development than men shows that the characteristics of the lift differ in both muscle actions. These data give novel insights into upper body bench press exercise characteristics in men and women using a robotic testing system. These data demonstrate that sticking points and the pattern of forces over the range of motion are different between men and women in maximal effort concentric and eccentric phases of the bench press exercise.
The purpose of this study was to examine markers of skeletal muscle tissue damage and circulating anabolic and catabolic hormones to gain insight into the recovery process from Friday until Monday, when a new practice week begins. Twenty-eight National Collegiate Athletic Association Division I football players gave consent to participate in the investigation in the ninth game of the season. Sixteen players started the game and played the entire game (PL), and 12 others did not play and were on the bench during the game (DNP). Each player had fasted blood samples obtained at the same time of day between 1000 and 1200 hours the day before the game (Friday; T1), 18-20 hours after the game (Sunday; T2), and then 42-44 hours after the game (Monday; T3). Blood samples were analyzed for concentrations of creatine kinase (CK), lactate dehydrogenase (LDH), myoglobin, testosterone, and cortisol. The PL players showed significantly (p T1 and T3), myoglobin (T2 > T1 and T3), and LDH (T2 > T1). In contrast, DNP players showed significant differences in cortisol (T3 < T1 and T2) and testosterone:cortisol (T3 > T1). Few changes were observed in testosterone and cortisol changes, indicating stability of the anabolic/catabolic hormones. In conclusion, these data indicate that participation in a college football game late in the season results in some degree of tissue damage but with minimal hormonal responses, which seem to have stabilized at resting concentrations without predominance of cortisol's catabolic presence. As previously noted in the literature, some type of "contact adaptation" to the season may have occurred with regard to tissue damage responses. However, by the ninth game of a season, players do carry soft tissue damage levels above resting ranges into subsequent games, indicating that recovery should be monitored, with coaches being careful with scheduling scrimmage and full-contact drills. How such data implicate overuse injuries remains unclear, considering that hormonal status in this study was highly stable, with catabolic influences minimized by the high level of athlete conditioning. These data again support that high-level conditioning can stabilize anabolic and catabolic hormonal signals and limit acute soft tissue injury, making cerebral concussion (acute and chronic) and traumatic injury the biggest threats to a student-athlete's health and well-being during an American football game.
This study compared caffeine pharmacokinetics, glycerol concentrations, metabolic rate, and performance measures following ingestion of a time-release caffeine containing supplement (TRCAF) 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.
In Brief Learning Objectives From this article, the reader should understand the following concepts in relation to designing resistance training programs: The dynamic program design and progress in optimizing resistance training programs Principles of individualization, overload, variation, and periodization Basic components of designing resistance training programs: a needs analysis, workout design, and changes with chronic programming How to use the acute program variables in designing and modifying resistance training programs Differentiation between linear periodized programs and a nonlinear periodized programs This article explains the design and evaluation of individualized resistance trainingprograms based on preliminary assessments and needs analyses that depict the selections in acute program variables, which, in turn, will dictate the exercise stimulifor the planned workouts over a given training cycle to reach or maintain desiredtraining goal.
