Indicators of Fatigue in Collegiate Women Tennis Players

To date very few research studies are available describing a detailed sports science profile of collegiate women tennis players, as many other existing studies only provide data on Junior tennis players or middle-aged subjects. The purpose of this investigation was to examine seasonal changes in training and competition on physiological and psychological measures in 13 NCAA Division I collegiate women tennis players (mean ± SD: age, 19.69 ± 1.32 years; height, 168.82 ± 4.59 cm; and weight, 64.75 ± 2.89 kg). All testing was conducted during the fall season. All subjects signed a University IRB approved informed consent form. Every two weeks (T1 - T6) subjects performed a maximal serve velocity test and an athlete burnout questionnaire (ABQ) from which the global burnout index (the mean score of the 3 ABQ subscales) was used. Subjects also completed a spider agility test and the Australian Sports Commission 20m shuttle run test at T1, T4, and T6. Lastly, the team indicated their ratings of perceived exertion (RPE) after every practice and conditioning session, which was later used to calculate training load (RPE x min). One Way ANOVA with repeated measures testing revealed no differences (p \u3e .05) in maximal serve velocity, spider agility test times, and global burnout index scores throughout the fall season. However 20m shuttle run test values revealed that aerobic capacity increased significantly (p \u3c0.05) from T1 to T4 (mean ± SD, 34.12 ± 4.50 ml/kg/min to 39.05 ± 4.55 ml/kg/min) with no differences between T4 and T6 (39.05 ± 4.55 ml/kg/min to 40.15 ± 3.62 ml/kg/min). The RPE results revealed that there was an fluctuating pattern in the teams training load, which decreased significantly (p \u3c 0.05) from T1 to T6 (mean ± SD, 3020.00 +/- 695.85 to 1933.33 ± 959.89). Dependent t-tests revealed significant differences (p \u3c 0.05) when comparing T1 (as baseline) to T6 in the athletes\u27 maximal (and average) serve velocity (mean ± SD, 146.45 ± 7.16 km/hr to 140.66 ± 7.96 km/hr), and global burnout scores (mean ± SD, 2.35 ± 0.50 to 2.54 ± 0.56). Therefore, fatigue as indicated by an increased global burnout index and decreased maximal serve velocity increased in women tennis players across their fall season even as workload decreased. In conclusion, it is vital for a conditioning program to be implemented during the three month summer break to which collegiate tennis teams can adhere. This would decrease the potential for detraining and ensure more time could be spent on other important determinants of tennis performance. Collegiate tennis coaches and strength and conditioning specialists should train tennis players in an anaerobic, tennis-specific manner that works the correct energy systems in order to accomplish the major goal of tennis training, which is to avoid the onset of fatigue during competition and practice

RELIABILITY AND ACCURACY OF A STANDARDIZED SHALLOW WATER RUNNING TEST TO DETERMINE CARDIORESPIRATORY FITNESS

A standardized fitness assessment is critical for the development of an individualized exercise prescription. Although the benefits of aquatic exercise have been well established, there remains the need for a standardized nonswimming protocol to accurately assess cardiorespiratory fitness (CRF) in shallow water. The present investigation was designed to assess (a) the reliability of a standardized shallow water run (SWR) test of CRF and (b) the accuracy of a standardized SWR compared with a land-based treadmill (LTM)test. Twenty-three healthy women (20 6 3 years), with body mass index (23.5 6 3 kg$m22), performed 2 shallow water peak oxygen consumption (V_ O2peak) running tests (SWRa and SWRb), and 1 V_ O2max LTM. Intraclass correlation coefficients indicated moderately strong reliability for V_ O2peak (ml$kg21$min21) (r = 0.73, p , 0.01), HR peak (b$min21) (r = 0.82; p , 0.01), and O2pulse (V_ O2 [ml$kg21$min21]$HR [b$min21]) (r = 0.77, p , 0.01). Using paired t-tests and Pearson’s correlations, SWR V_ O2peak and HR peak were significantly lower than during LTM (p # 0.05) and showed moderate correlations of 0.60 and 0.58 (p , 0.001) to LTM. O2pulse was similar (p . 0.05) for the SWR and LTM tests with a moderate correlation of 0.63. A standardized SWR test asa measure of CRF is a reliable, and to some degree, valid alternative to conventional protocols and may be used by strength and conditioning professionals to measure program outcomes and monitor training progress. Furthermore, this protocol provides a water-based option for CRF assessment among healthy women and offers insight toward the development of an effective protocol that can accommodate individuals with limited mobility, or those seeking less musculoskeletal impact from traditional land-based types of training

Relations Between Timing Features and Colors in the X-Ray Binary 4U 0614+09

We study the correlations between timing and X-ray spectral properties in the low mass X-ray binary 4U 0614+09 using a large (265-ks) data set obtained with the Rossi X-ray Timing Explorer. We find strong quasi-periodic oscillations (QPOs) of the X-ray flux, like the kilohertz QPOs in many other X-ray binaries with accreting neutron stars, with frequencies ranging from 1329 Hz down to 418 Hz and, perhaps, as low as 153 Hz. We report the highest frequency QPO yet from any low mass X-ray binary at 1329+-4 Hz, which has implications for neutron star structure. This QPO has a 3.5-sigma single-trial significance, for an estimated 40 trials the significance is 2.4-sigma. Besides the kilohertz QPOs, the Fourier power spectra show four additional components: high frequency noise (HFN), described by a broken power-law with a break frequency between 0.7 and 45 Hz, very low frequency noise (VLFN), which is fitted as a power-law below 1 Hz, and two broad Lorentzians with centroid frequencies varying from 6 to 38 Hz and 97 to 158 Hz, respectively. We find strong correlations between the frequencies of the kilohertz QPOs, the frequency of the 6 to 38 Hz broad Lorentzian, the break frequency of the HFN, the strength of both the HFN and the VLFN and the position of the source in the hard X-ray color vs. intensity diagram. The frequency of the 97 to 158 Hz Lorentzian does not correlate with these parameters. We also find that the relation between power density and break frequency of the HFN is similar to that established for black hole candidates in the low state. We suggest that the changing mass accretion rate is responsible for the correlated changes in all these parameters.Comment: ApJ, referee

Synergistic Effects of Hypofibrinolysis and Genetic and Acquired Risk Factors on the Risk of a First Venous Thrombosis

Frits Rosendaal and colleagues show that the combination of hypofibrinolysis with oral contraceptive use, immobilization, or factor V Leiden results in a risk of venous thrombosis that exceeds the sum of the individual risks

Recommendations for the Management of Hepatitis C Virus Infection Among People Who Inject Drugs

In the developed world, the majority of new and existing hepatitis C virus (HCV) infections occur among people who inject drugs (PWID). The burden of HCV-related liver disease in this group is increasing, but treatment uptake among PWID remains low. Among PWID, there are a number of barriers to care that should be considered and systematically addressed, but these barriers should not exclude PWID from HCV treatment. Furthermore, it has been clearly demonstrated that HCV treatment is safe and effective across a broad range of multidisciplinary healthcare settings. Given the burden of HCV-related disease among PWID, strategies to enhance HCV assessment and treatment in this group are urgently needed. These recommendations demonstrate that treatment among PWID is feasible and provides a framework for HCV assessment, management, and treatment. Further research is needed to evaluate strategies to enhance assessment, adherence, and SVR among PWID, particularly as new treatments for HCV infection become availabl

Perturbed Rotations of a Rigid Body Close to the Lagrange Case under the Action of Unsteady Perturbation Torques

Perturbed rotations of a rigid body close to the Lagrange case under the action of perturbation torques slowly varying in time are investigated. Conditions are presented for the possibility of averaging the equations of motion with respect to the nutation angle and the averaged system of equations of motion is obtained. In the case of the rotational motion of the body in the linear-dissipative medium the numerical integration of the averaged system of equations is conducted

Integration of evidence across human and model organism studies: A meeting report.

The National Institute on Drug Abuse and Joint Institute for Biological Sciences at the Oak Ridge National Laboratory hosted a meeting attended by a diverse group of scientists with expertise in substance use disorders (SUDs), computational biology, and FAIR (Findability, Accessibility, Interoperability, and Reusability) data sharing. The meeting\u27s objective was to discuss and evaluate better strategies to integrate genetic, epigenetic, and \u27omics data across human and model organisms to achieve deeper mechanistic insight into SUDs. Specific topics were to (a) evaluate the current state of substance use genetics and genomics research and fundamental gaps, (b) identify opportunities and challenges of integration and sharing across species and data types, (c) identify current tools and resources for integration of genetic, epigenetic, and phenotypic data, (d) discuss steps and impediment related to data integration, and (e) outline future steps to support more effective collaboration-particularly between animal model research communities and human genetics and clinical research teams. This review summarizes key facets of this catalytic discussion with a focus on new opportunities and gaps in resources and knowledge on SUDs