scholarly journals Effect of a Simulated Match on Lower Limb Neuromuscular Performance in Youth Footballers—A Two Year Longitudinal Study

2020 ◽  
Vol 17 (22) ◽  
pp. 8579
Author(s):  
Michal Lehnert ◽  
Mark De Ste Croix ◽  
Amr Zaatar ◽  
Patrycja Lipinska ◽  
Petr Stastny
Keyword(s):  
Vastus Lateralis ◽  
Age Groups ◽  
Quadriceps Strength ◽  
Firing Frequency ◽  
Strength Parameters ◽  
Match Play ◽  
Neuromuscular Performance ◽  
Leg Stiffness ◽  
Age Dependent ◽  
Simulated Match

The aim of this study was to explore the effects of simulated soccer match play on neuromuscular performance in adolescent players longitudinally over a two-year period. Eleven players completed all measurements in both years of the study (1st year: age 16.0 ± 0.4 y; stature 178.8 ± 6.4 cm; mass 67.5 ± 7.8 kg; maturity-offset 2.24 ± 0.71 y). There was a significant reduction in hamstring strength after simulated match by the soccer-specific aerobic field test (SAFT90), with four out of eight parameters compromised in U16s (4.7–7.8% decrease) and six in the U17s (3.1–15.4%). In the U17s all of the concentric quadriceps strength parameters were decreased (3.7–8.6%) as well as the vastus lateralis and semitendinosus firing frequency (26.9–35.4%). In both ages leg stiffness decreased (9.2–10.2%) and reactive strength increased pre to post simulated match (U16 8.0%; U17 2.5%). A comparison of changes between age groups did not show any differences. This study demonstrates a decrease in neuromuscular performance post simulated match play in both ages but observed changes were not age dependent.

Do Running Activities of Adolescent and Adult Tennis Players Differ During Play?

2016 ◽  
Vol 11 (6) ◽  
pp. 793-801 ◽  
Author(s):  
Matthias W. Hoppe ◽  
Christian Baumgart ◽  
Jürgen Freiwald
Keyword(s):  
Inertial Sensor ◽  
Age Groups ◽  
Portable Devices ◽  
Metabolic Power ◽  
Match Play ◽  
Intensity Measures ◽  
Tennis Players ◽  
Global Positioning ◽  
Recorded Data ◽  
Simulated Match

Purpose:To investigate differences in running activities between adolescent and adult tennis players during match play. Differences between winning and losing players within each age group were also examined.Methods:Forty well-trained male players (20 adolescents, 13 ± 1 y; 20 adults, 25 ± 4 y) played a simulated singles match against an opponent of similar age and ability. Running activities were assessed using portable devices that sampled global positioning system (10 Hz) and inertial-sensor (accelerometer, gyroscope, and magnetometer; 100 Hz) data. Recorded data were examined in terms of velocity, acceleration, deceleration, metabolic power, PlayerLoad, and number of accelerations toward the net and the forehand and backhand corners.Results:Adult players spent more time at high velocity (≥4 m/s2), acceleration (≥4 m/s2), deceleration (≤–4 m/s2), and metabolic power (≥20 W/kg) (P ≤ .009, ES = 0.9–1.5) and performed more accelerations (≥2 m/s2) toward the backhand corner (P < .001, ES = 2.6–2.7). No differences between adolescent winning and losing players were evident overall (P ≥ .198, ES = 0.0–0.6). Adult winning players performed more accelerations (2 to <4 m/s2) toward the forehand corner (P = .026, ES = 1.2), whereas adult losing players completed more accelerations (≥2 m/s2) toward the backhand corner (P ≤ .042, ES = 0.9).Conclusions:This study shows that differences in running activities between adolescent and adult tennis players exist in high-intensity measures during simulated match play. Furthermore, differences between adolescent and adult players, and also between adult winning and losing players, are present in terms of movement directions. Our findings may be helpful for coaches to design different training drills for both age groups of players.

COVID - 19 AND THE PROBLEM OF PERSONALITY

2020 ◽  
pp. 31-35
Author(s):  
Mazaeva N.A. ◽  
Golovina A.G.
Keyword(s):  
General Population ◽  
Age Groups ◽  
Personal Transformation ◽  
Personality Changes ◽  
Age Dependent

In order to determine possible trends in the dynamics and characterological structure of personality in the General population caused by the COVID-19 pandemic, which is a long-term strong stressful effect and clinically and psychopathologically comparable to chronic personality changes after experiencing a disaster, the conditions predisposing to personal transformation, including clinical and prognostic patterns, are analyzed. The age-dependent nature of these changes is shown, and a number of features identified for different age groups are discussed.

scholarly journals 1465. Age-Dependent Interactions Among Clinical Characteristics, Viral Loads and Disease Severity in Young Children with Respiratory Syncytial Virus Infection (RSV) Infection

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S734-S735
Author(s):  
Helena Brenes-Chacon ◽  
Cristina Garcia-Maurino ◽  
Melissa Moore-Clingenpeel ◽  
Sara Mertz ◽  
Fang Ye ◽  
...  
Keyword(s):  
Young Children ◽  
Disease Severity ◽  
Age Groups ◽  
Panel Member ◽  
Signs And Symptoms ◽  
Research Support ◽  
Review Panel ◽  
Viral Loads ◽  
Age Dependent ◽  
Rsv Infection

Abstract Background Differences in clinical presentation and viral loads according to age in young children with RSV, and their correlation with disease severity are poorly defined. The aim of this study was to define age-dependent the differences in demographic, clinical factors and viral loads between children &lt; 2 years of age with mild RSV infection evaluated as outpatients versus those hospitalized with severe RSV infection. Figure 1. Sign and Symptoms according to disease severity and age in infants with RSV infection. Most relevant signs and symptoms were stratified in outpatients (orange) vs inpatients (blue) by age in (A) &lt; 3 months, (B) between 3 and 6 months, and (C) &gt; 6 to 24 months of age. The Y axis represents the signs and symptoms in the two disease severity groups and the X axis the frequency of that specific symptom (%). Numbers next to bars represent the exact number of patients with that specific sign/symptom. Comparisons by Fisher exact test. Symbol (*) indicate significant 2-sided p values Figure 2. Viral load differences according to age in infants with RSV infection. The Y axis represents RSV loads in log10 copies/mL and the X axis differences in viral loads in outpatients (orange) and inpatients (blue) in the three age groups. Comparisons by Mann Whitney test. Methods Previously healthy children &lt; 2 years old with mild (outpatients) and severe (inpatients) RSV infection were enrolled and nasopharyngeal swabs were obtained for RSV typing and quantitation by real-time PCR. Patients were stratified by age (0-&lt; 3, 3-6, and &gt;6-24 months) and multivariable analyses were performed to identify clinical and viral factors associated with severe disease. Results From 2014-2018 we enrolled 534 children with RSV infection: 130 outpatients and 404 inpatients. Median duration of illness was 4 days for both groups, yet viral loads were higher in outpatients than inpatient in the three age groups (Fig 1). Wheezing was more frequent in outpatients of older age (&gt;3 months) than in inpatients (p&lt; 0.01), while fever was more common in inpatients that outpatients (p&lt; 0.01) and increased with age (Fig 2). Adjusted analyses confirmed that increased work of breathing and fever were consistently associated with hospitalization irrespective of age, while wheezing in infants &gt;3 months, and higher RSV loads in children &gt;6-24 months were independently associated with reduced disease severity. Conclusion Age had a significant impact defining the interactions among viral loads, specific clinical manifestations and disease severity in children with RSV infection. These observations highlight the importance of patient stratification when evaluating interventions against RSV. Disclosures Octavio Ramilo, MD, Bill & Melinda Gates Foundation (Grant/Research Support)Janssen (Grant/Research Support, Advisor or Review Panel member)Medimmune (Grant/Research Support)Merck (Advisor or Review Panel member)NIH/NIAID (Grant/Research Support)Pfizer (Consultant, Advisor or Review Panel member)Sanofi/Medimmune (Consultant, Advisor or Review Panel member) Asuncion Mejias, MD, PhD, MsCS, Janssen (Grant/Research Support, Advisor or Review Panel member)Merck (Advisor or Review Panel member)Roche (Advisor or Review Panel member)

scholarly journals Could age increase the strength of inverse association between ultraviolet B exposure and colorectal cancer?

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Vidya Lakshmi Purushothaman ◽  
Raphael E. Cuomo ◽  
Cedric F. Garland ◽  
Timothy K. Mackey
Keyword(s):  
Colorectal Cancer ◽  
Vitamin D ◽  
Vitamin D Deficiency ◽  
Age Groups ◽  
Incidence Rates ◽  
Ultraviolet B ◽  
Inverse Association ◽  
Crude Incidence ◽  
Age Dependent ◽  
Uvb Exposure

Abstract Background Vitamin D has been identified as a potential protective factor in the development of colorectal cancer (CRC). We expect to see a stronger association of ultraviolet B (UVB) exposure and CRC crude rates with increasing age since chronic vitamin D deficiency leads to sustained molecular changes that increase cancer risk. The DINOMIT (disjunction, initiation, natural selection, overgrowth, metastasis, involution, and transition) model postulates various stages of cancer development due to vitamin D deficiency and the associated latency period. The purpose of this study is to examine this age-dependent inverse relationship globally. Methods In this ecological study, a series of linear and polynomial regression tests were performed between country-specific UVB estimates adjusted for cloud cover and crude incidence rates of CRC for different age groups. Multiple linear regression was used to investigate the association between crude incidence rates of colorectal cancer and UVB estimate adjusting for urbanization, skin pigmentation, smoking, animal consumption, per capita GDP, and life expectancy. Statistical analysis was followed by geospatial visualization by producing choropleth maps. Results The inverse relationship between UVB exposure and CRC crude rates was stronger in older age groups at the country level. Quadratic curve fitting was preferred, and these models were statistically significant for all age groups. The inverse association between crude incidence rates of CRC and UVB exposure was statistically significant for age groups above 45 years, after controlling for covariates. Conclusion The age-dependent inverse association between UVB exposure and incidence of colorectal cancer exhibits a greater effect size among older age groups in global analyses. Studying the effect of chronic vitamin D deficiency on colorectal cancer etiology will help in understanding the necessity for population-wide screening programs for vitamin D deficiency, especially in regions with inadequate UVB exposure. Further studies are required to assess the need for adequate public health programs such as selective supplementation and food fortification.

scholarly journals Aging and acute exercise enhance free radical generation in rat skeletal muscle

1999 ◽  
Vol 87 (1) ◽  
pp. 465-470 ◽  
Author(s):  
J. Bejma ◽  
L. L. Ji
Keyword(s):  
Skeletal Muscle ◽  
Lipid Peroxidation ◽  
Acute Exercise ◽  
Muscle Protein ◽  
Vastus Lateralis ◽  
Age Groups ◽  
Protein Carbonyl ◽  
Biological Aging ◽  
Young Rats ◽  
Old Rats

Reactive oxygen species (ROS) are implicated in the mechanism of biological aging and exercise-induced oxidative damage. The present study examined the effect of an acute bout of exercise on intracellular ROS production, lipid and protein peroxidation, and GSH status in the skeletal muscle of young adult (8 mo, n = 24) and old (24 mo, n = 24) female Fischer 344 rats. Young rats ran on a treadmill at 25 m/min and 5% grade until exhaustion (55.4 ± 2.7 min), whereas old rats ran at 15 m/min and 5% grade until exhaustion (58.0 ± 2.7 min). Rate of dichlorofluorescin (DCFH) oxidation, an indication of ROS and other intracellular oxidants production in the homogenate of deep vastus lateralis, was 77% ( P < 0.01) higher in rested old vs. young rats. Exercise increased DCFH oxidation by 38% ( P < 0.09) and 50% ( P < 0.01) in the young and old rats, respectively. DCFH oxidation in isolated deep vastus lateralis mitochondria with site 1 substrates was elevated by 57% ( P < 0.01) in old vs. young rats but was unaltered with exercise. Significantly higher DCFH oxidation rate was also found in aged-muscle mitochondria ( P < 0.01), but not in homogenates, when ADP, NADPH, and Fe3+ were included in the assay medium without substrates. Lipid peroxidation in muscle measured by malondialdehyde content showed no age effect, but was increased by 20% ( P < 0.05) with exercise in both young and old rats. Muscle protein carbonyl formation was unaffected by either age or exercise. Mitochondrial GSH/ GSSG ratio was significantly higher in aged vs. young rats ( P < 0.05), whereas exercise increased GSSG content and decreased GSH/GSSG in both age groups ( P < 0.05). These data provided direct evidence that oxidant production in skeletal muscle is increased in old age and during prolonged exercise, with both mitochondrial respiratory chain and NADPH oxidase as potential sources. The alterations of muscle lipid peroxidation and mitochondrial GSH status were consistent with these conclusions.

Different ATP-catabolism in reperfused adult and newborn rat hearts

1988 ◽  
Vol 254 (6) ◽  
pp. H1091-H1098
Author(s):  
P. W. Achterberg ◽  
A. S. Nieukoop ◽  
B. Schoutsen ◽  
J. W. de Jong
Keyword(s):  
Oxidase Activity ◽  
Age Groups ◽  
Similar Degree ◽  
Ischemia And Reperfusion ◽  
Xanthine Oxidoreductase ◽  
Newborn Rat ◽  
Age Related ◽  
Rat Hearts ◽  
Age Dependent ◽  
Atp Breakdown

Age-dependent differences in the effects of ischemia and reperfusion on ATP breakdown were studied in perfused adult and newborn (10 days old) rat hearts. No-flow ischemia (15 min at 37, 30, or 23 degrees C) was applied and reperfusion (20 min at 37 degrees C) was studied after ischemia at 23 or 37 degrees C. Hypothermia during ischemia protected both age groups to a similar degree against ATP decline, which was linear with temperature. Reperfusion after normothermic ischemia resulted in higher ATP levels in newborn hearts with less release of ATP catabolites (purines). We found no age-related differences in lactate release but large differences in purine release. During normoxia, adult hearts released mainly urate (80% of total) and inosine (7%), but newborns released hypoxanthine (64%) and inosine (15%). Early during reperfusion adult hearts released inosine (58%) and adenosine (18%), but newborns released inosine (53%) and hypoxanthine (38%). These data suggested a lower activity of the potentially deleterious enzyme xanthine oxidoreductase in newborn hearts, which was confirmed by enzymatic assay. ATP-catabolite release during reperfusion was less in newborn than adult hearts, and this coincided with lower xanthine oxidase activity.

scholarly journals Studies on Spontaneous Platelet Aggregation (PAT III) in Patients with Vascular Disease

1977 ◽  
Author(s):  
H.J. Krzywanek ◽  
K. Breddin
Keyword(s):  
Platelet Aggregation ◽  
Healthy Subjects ◽  
Age Groups ◽  
Arterial Disease ◽  
Peripheral Occlusive Arterial Disease ◽  
Age Dependent ◽  
Patient Groups ◽  
The Difference ◽  
Spontaneous Platelet Aggregation ◽  
Prospective Investigation

Aggregation tests were performed in 345 patients with peripheral occlusive arterial disease (PAD), 274 patients with coronary heart disease (CHD), and 502 diabetics (D). 263 healthy volunteers (N) served as controls. As in previous studies an age dependent increase of strongly enhanced spontaneous platelet aggregation in obviously healthy subjects can be demonstrated, reaching 28% in the 50-59 years’age group. In the various patient groups the incidence of enhanced aggregation is much higher throughout all age groups than in the control s.The overall incidence of missing spontaneous platelet aggregation vs. strongly enhanced aggregation is summarized below. The difference between normals and the various patient groups is significant (X2-test, α<0.0001).A prospective investigation has been started to establish whether enhanced spontaneous platelet aggregation is a risk factor and an early indicator of progressive atherosclerosis.

scholarly journals Age-dependent increase of treatment-related mortality in older patients with aggressive B cell lymphoma: analysis of outcome, treatment feasibility, and toxicity in 1171 elderly patients with aggressive B cell lymphoma—data from phase II and III trials of the DSHNHL (German High-Grade Non-Hodgkin’s Lymphoma Study Group)

2020 ◽  
Author(s):  
Florian Zettl ◽  
Marita Ziepert ◽  
Bettina Altmann ◽  
Samira Zeynalova ◽  
Gerhard Held ◽  
...  
Keyword(s):  
Elderly Patients ◽  
B Cell ◽  
Patient Population ◽  
Cell Lymphoma ◽  
Age Groups ◽  
Progression Free Survival ◽  
B Cell Lymphoma ◽  
Free Survival ◽  
Age Dependent ◽  
Aggressive B Cell Lymphoma

AbstractIn elderly patients (pts) with aggressive B cell lymphoma (aNHL), curative treatment often cannot be administered because of comorbidities and tolerability. We analyzed the influence of age in pts > 60 years receiving the R-CHOP-14 regimen within different prospective DSHNHL trials. Of the RICOVER-60 trial and CHOP-R-ESC trials, 1171 aNHL pts were included in this retrospective analysis of age-dependent event-free survival (EFS), progression-free survival (PFS), and overall survival (OS). All patients received prophylactic G-CSF, and anti-infective prophylaxis with amphotericin B mouth wash and oral fluorchinolone was optional. In the CHOP-R-ESC trials, prophylaxis was augmented to include mandatory continuous orally administered aciclovir and a pneumocystis prophylaxis with cotrimoxazole as well as oral fluorchinolones during neutropenia. The patient population was separated into 4 age groups (61–65 years, 66–70 years, 71–75 years, and 76–80 years). The results from the RICOVER-60 trial were subsequently confirmed in the following CHOP-R-ESC trials by a multivariate analysis adjusted for IPI factors and gender. Significant differences (p < 0.001) in EFS, PFS, and OS were seen between age groups (RICOVER-60). Hematotoxicity, infections, and TRM increased with age. TRM was significantly elevated in the age group 76–80 years. Therefore, this analysis shows that an age above 75 years defines an especially vulnerable patient population when being treated with chemoimmunotherapy for aNHL. Prophylactic anti-infective drugs are essential and clinically effective in reducing morbidity when treating elderly aNHL pts.

Age-Dependent Biphasic Changes in Ischemic Sensitivity in the Striatum of Huntington's Disease R6/2 Transgenic Mice

2005 ◽  
Vol 93 (2) ◽  
pp. 758-765 ◽  
Author(s):  
Gloria J. Klapstein ◽  
Michael S. Levine
Keyword(s):  
Huntington's Disease ◽  
Huntington’S Disease ◽  
Glutamate Release ◽  
Age Groups ◽  
Brain Slices ◽  
Glucose Deprivation ◽  
Behavioral Phenotype ◽  
Crossover Point ◽  
Glutamate Receptor Antagonist ◽  
Age Dependent

We used the oxygen/glucose deprivation (OGD) model of ischemia in corticostriatal brain slices to test the hypothesis that metabolic deficiencies in R6/2 transgenic Huntington's disease (HD) mice will impair their recovery from an ischemic challenge. Corticostriatal extracellular field excitatory postsynaptic potentials (fEPSPs) were evoked in transgenic and wild-type (WT) mice in three age groups: 3–4 wk, before the overt behavioral phenotype develops; 5–9 wk, as overt behavioral symptoms begin; and 10–15 wk when symptoms were most severe. OGD for 8 min completely and reversibly inhibited fEPSPs. Although responses of 3–4 wk WTs showed a tolerance to ischemia and recovered rapidly, ischemic sensitivity developed progressively; at 5–9 and 10–15 wk, responses recovered more slowly from OGD. In contrast, although 3–4 wk R6/2 transgenic fEPSPs showed significantly more ischemic sensitivity than their WT counterparts, the R6/2 fEPSPs maintained a relative tolerance to ischemia at 5–9 and 10–15 wk. As a result, a “crossover” point occurred, roughly coinciding with the development of the overt behavioral phenotype (5–9 wk), after which time R6/2 fEPSPs were significantly more resistant to ischemia than WT responses. The increased ischemic sensitivity in 3–4 wk R6/2 responses was not due to excessive glutamate release during OGD as it persisted in the presence of the glutamate receptor antagonist kynurenic acid (1 mM). Although the mechanism for development of ischemic resistance in R6/2 transgenics remains unknown, it correlates with metabolic and biochemical changes described in this model and in HD patients.

Trends in the Incidence of Legal Problems and in the Use of Lawyers

1978 ◽  
Vol 3 (2) ◽  
pp. 289-313 ◽  
Author(s):  
Yakov Avichai
Keyword(s):  
Mathematical Model ◽  
Age Groups ◽  
Strong Increase ◽  
Government Regulations ◽  
Legal Problems ◽  
Socioeconomic Changes ◽  
Age Dependent ◽  
Changes Over Time ◽  
Near Future ◽  
Over Time

Changes in the law, government regulations, socioeconomic changes, increased consumerism, the public's level of awareness—all these and other factors influence the population's demand over time for lawyers' services. This article analyzes the changes over time in the two elements that determine the demand for lawyers: the number of legal problems encountered by the population and the rate of use of lawyers in solving these problems. After showing that sequential occurrences of legal problems are not independent of each other and are age dependent, the author develops a mathematical model that explains the variability in the present number of problems encountered by different age groups. The number of problems is found to result from a relatively mild accumulation with age of legal problems, coupled with a strong increase in the number of problems from generation to generation. The analysis of individual legal problems reveals a variety of patterns from problem to problem in both the level of occurrence and the rate of use of lawyers for such problems. The author concludes that the combined effect of occurrence and utilization will operate toward a continuing increase in the demand for lawyers'services at least for the very near future.

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