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21.
Christine Holm Moseid Grethe Myklebust Marit Kyte Slaastuen Jonathan Brun Bar‐Yaacov Aase Helen Kristiansen Morten Wang Fagerland Roald Bahr 《Scandinavian journal of medicine & science in sports》2019,29(11):1736-1748
Youth elite athletes often double their training and competition load after enrollment into specialized sport academy high school programs. The least fit athletes may be exposed to an excessive and too rapid increase in training load, with negative adaptations such as injury and illness as a consequence. In this study, our aim was to determine whether these least fit athletes were at greater risk of injury or illness during their first school year. Participants were 166 youth elite athletes (72% boys) from a variety of team, technical, and endurance sports newly enrolled into specialized sport academy high schools. The Oslo Sports Trauma Research Center Questionnaire on Health Problems was used to self‐report injuries and illnesses weekly for 26 weeks. Athletes completed the Ironman Jr physical fitness test battery at baseline, evaluating endurance, strength, agility, and speed properties. We ranked the athletes based on their combined test scores and identified the least fit quartile. The main outcome was the number and severity of health problems, comparing the least fit quartile of athletes to the rest of the cohort. Overall, the least fit quartile of athletes did not report more health problems (mean 3.7, 95% CI 3.0‐4.4) compared with the rest of the cohort (3.6, 3.2‐3.9). In conclusion, we demonstrated no association between low physical fitness level and number and severity of injury and illness in youth elite athletes after enrollment into a specialized sport academy high school program. 相似文献
22.
Joar Hary Espen Guldahl Wiger Roald Bahr Thor Einar Andersen 《Scandinavian journal of medicine & science in sports》2019,29(8):1092-1100
Groin injuries represent a considerable problem in male football, accounting for 4%‐19% of all time‐loss injuries. The Adductor Strengthening Programme is the first groin‐specific prevention program shown to reduce the risk of groin problems. We aimed to use the RE‐AIM framework to examine the players’ experiences with the implementation of the program and player attitude toward groin injury prevention in football. Of the 632 players involved in the trial examining the effect of the Adductor Strengthening Programme, 501 agreed to participate in a survey at the end of the season. Most players thought that footballers are at moderate to high risk for groin injuries (87%) and that there is a need for preventive measures (96%). They also believed that a preventive program with strengthening exercises would reduce the risk of groin injuries (91%). Majority of the players reported using <5 minutes to complete the program (73%), and only 11% wanted additional exercises. However, only 46% reported to have performed the program as recommended, and an even smaller proportion (31%) planned to continue using it as recommended the next season. Our results suggest that footballers believe that prevention of groin injuries is needed. Attitude toward implementation of the Adductor Strengthening Programme was positive, and the single‐exercise approach was considered an important facilitator. However, in future dissemination of the program, the players’ reluctance to maintain the exercise protocol may be a potential barrier to implementation that should be addressed. 相似文献
23.
Rhythm perception: Speeding up or slowing down affects different subcomponents of the ERP P3 complex
The aim of this study was to investigate, by measuring the event related potential (ERP) P3 complex, whether the perception of small accelerations differs from that of small decelerations. Participants had to decide whether the last beat of a short sequence was presented 'too early' or 'too late'. Target beats were accelerated or decelerated with 0%, 2%, 5%, or 10%. Individuals differed in their capability to detect small tempo changes. We found that good responders were able to identify all tempo changes whereas poor responders were only able to identify large (10%) tempo changes. In addition, we found that tempo changes affected two subcomponents of the ERP P3 in good performers. Accelerations increased a late-P3 amplitude whereas decelerations increased an early-P3 amplitude. These results imply the principle possibility to measure differential P3 effects within one task. This is important for acquiring more refined knowledge concerning different subcomponents of the ERP P3 complex and the cognitive processes by which they are elicited. 相似文献
24.
Koerte Inga K. Bahr Roald Filipcik Peter Gooijers Jolien Leemans Alexander Lin Alexander P. Tripodis Yorghos Shenton Martha E. Sochen Nir Swinnen Stephan P. Pasternak Ofer 《Brain imaging and behavior》2022,16(1):492-502
Brain Imaging and Behavior - Repetitive head impacts (RHI) are common in youth athletes participating in contact sports. RHI differ from concussions; they are considered hits to the head that... 相似文献
25.
Stian Bahr Sandmo Thor Einar Andersen Inga Katharina Koerte Roald Bahr 《Scandinavian journal of medicine & science in sports》2020,30(1):193-198
Restrictions on heading in youth football have been implemented in some countries to limit head impact exposure. However, current interventions remain poorly guided by evidence. Our objective was to quantify heading exposure in youth football, assessing the effects of sex and age. Football matches played during an international youth football tournament with no heading restrictions were directly observed, including players from both sexes (11-19 years). The elite senior level was included for comparison, using video analysis. All heading events were registered, classified, and assigned to individual players. Heading rates were calculated for each sex and age group. We observed a total of 267 matches, corresponding to 4011 player hours (1927 player hours for females, 2083 player hours for males). Males headed more frequently than females (2.7 vs 1.8 headers/player hour; P < .001). Heading rates increased with age (ANOVA, P < .001), approaching the elite senior level for players 16 years and older. There was substantial variation within teams for all age and sex groups, with the widest range (1-18 headers) observed for girls aged 19. Girls younger than 12 years had the lowest exposure, with an average of <2 players per team heading the ball, each with 1-2 headers. In conclusion, age and sex influence head impact exposure in youth football, and warrants careful consideration when introducing injury prevention measures. Males are more frequently exposed than females, heading rates increase with age, and there is substantial variation between players. Heading is a rare event in the youngest age groups, especially among females. 相似文献
26.
Impact of pollution and place of residence on atopic diseases among schoolchildren in Telemark County, Norway 总被引:2,自引:0,他引:2
Jon Steen-Johnsen R. Bolle J. Holt K. Benan P. Magnus 《Pediatric allergy and immunology》1995,6(4):192-199
For estimation of the prevalence, degree of severity, and association with outdoor pollution, a questionnaire on asthma and other atopic diseases was distributed to the parents of 4666 7–13-year-olds, comprising all the children in 36 schools in Telemark County, Norway, including 37% of the schoolchildren in the county. The response rate was 94%. In a validity study employing clinical evaluations, the questionnaire-based diagnosis of asthma was found to have a sensitivity of 0.96 and a specificity of 0.88. The lifetime prevalence of asthma in Telemark was 9% (boys 11.3%, girls 6.6% p < 0.001). There was no significant difference in the lifetime prevalence of asthma by pollution zone; 8.3% in heavily, 9.3% in moderately, and 9.2% in minimally polluted zones. The asthma prevalence was significantly higher (14.2% p < 0.05) among boys in the coastal area of the county than in the mountainous area (8.9%). Both of these areas were in the minimal pollution zone. Of asthma cases, 67% were categorized as mild, 29% as moderate, and 4% as severe. The lifetime prevalence was 17.8% (boys 21.3%, girls 14.2% p < 0.001) for allergic rhinitis, 13.2% (boys 11.4%, girls 15.2% p < 0.001) for atopic eczema, and 29.6% (boys 31.7%, girls 27.4% p < 0.01) for overall atopic disease (asthma, allergic rhinitis, eczema). These findings are not compatible with the hypothesis that outdoor pollution is associated with the lifetime prevalence of asthma in school-age children. The results also show that less than 0.5% of schoolchildren suffer from severe asthma. 相似文献
27.
Apeland T Mansoor MA Pentieva K McNulty H Seljeflot I Strandjord RE 《Epilepsy research》2002,51(3):237-247
Patients on antiepileptic drugs (AEDs) may have elevated levels of plasma total homocysteine (p-tHcy). The aim of this study was to assess the effect of B-vitamin supplementation on the levels of p-tHcy and markers of endothelial activation and lipid peroxidation. A total of 33 adult patients on AEDs were identified with either fasting (Group 1, n=23) or post methionine load (PML) (Group 2, n=10) hyperhomocysteinemia. Subjects were supplemented with B-vitamins for 30 days: folic acid 0.4 mg, pyridoxine 120 mg and riboflavin 75 mg per day. After supplementation, serum folate and pyridoxal phosphate had increased, while fasting and PML p-tHcy had decreased (P<0.0001) by 36 and 26%, respectively. Prior to supplementation, the Group 1 patients had elevated levels of P-selectin and von Willebrand factor (vWF) (P=0.05 and 0.03, respectively). After supplementation, the levels of intercellular cell adhesion molecules had decreased (P=0.01) and E-selectin decreased nonsignificantly (P=0.07). However, the levels of vascular cell adhesion molecules had increased (P<0.0001), while lipid peroxidation were unchanged. In conclusion, the combined supplementation with folic acid, pyridoxine and riboflavin reduced fasting and PML hyperhomocysteinemia in patients on AEDs. Patients with fasting hyperhomocysteinemia had elevated levels of P-selectin and vWF, which may indicate an increased risk of cardiovascular disease. Furthermore, B-vitamin supplementation influenced endothelial activation, although the clinical implication is uncertain. 相似文献
28.
Ramaz D. Katsarava Tamara M. Kartvelishvili Nona N. Japaridze Tsisana A. Goguadze Tamara A. Khosruashvili Roald P. Tiger Pjotr A. Berlin 《Macromolecular chemistry and physics.》1993,194(12):3209-3228
New polycondensation reactions of active diphenyl carbonates and diphenyl carbamate with diamines were developed for the synthesis of high-molecular-weight polyureas. The kinetics and mechanism of carbonic acid active esters aminolysis model reactions were studied. Possible side reactions including nucleophilic substitution reaction were investigated as well. It is shown that novel methods advantageously distinguish from traditional methods of polyureas synthesis by low tendency to side reactions and facilitate the synthesis of linear polyureas and copolyureas. It is found that N,N′-bis(trimethylsilylated) diamines and salts of diamines as monomers can be successfully used in these reactions. Bioanalogous polymers promising for biomedical application — polyureas based on L -lysine — were synthesized using novel polycondensation reactions. 相似文献
29.
Bang B Aasmoe L Aamodt BH Aardal L Andorsen GS Bolle R Bøe R Van Do T Evans R Florvåg E Gram IT Huser PO Kramvik E Løchen ML Pedersen B Rasmussen T 《Journal of occupational and environmental medicine / American College of Occupational and Environmental Medicine》2005,47(5):482-492
OBJECTIVE: In this study, we explored airway symptoms and exposure to bioaerosols and exhaust gases in seafood industry plants. METHODS: The study details the results from personal and environmental exposure measurements (17 plants), a questionnaire (n = 984), and clinical examinations (n = 225). RESULTS: The workers were exposed to allergens, endotoxins, molds, and exhaust. The 1-year prevalence of work-related airway symptoms was 42.8% for production workers and 25.9% for administrative workers. Mean levels of forced expiratory volume in 1 second and forced vital capacity were less than the predicted values in all exposed nonsmoker groups. A total of 20.5% had increased levels of total IgE (>/=100 kU/L). Specific IgE-mediated reactions seemed to be relevant only in the shrimp industry. CONCLUSIONS: Seafood industry workers showed a high prevalence of work-related airway symptoms. Further research on the relationship between exposure and effects is necessary. 相似文献
30.
Fatigue in patients with lupus is not associated with disturbances in cerebral blood flow as detected by SPECT 总被引:1,自引:0,他引:1
Omdal R Sjöholm H Koldingsnes W Sundsfjord JA Jacobsen EA Husby G Mellgren SI 《Journal of neurology》2005,252(1):78-83
Abstract
Objectives
Fatigue is a common complaint in patients with systemic lupus erythematosus (SLE). We investigated whether focal or general disturbances of cerebral blood flow (CBF), as assessed by SPECT, were associated with the presence of fatigue in an unselected group of SLE patients.
Methods
Fifty-six patients were included. Mean age was 47.5 years (±12.7), mean disease duration 14.7 years (±8.9), and disease activity measured by SLE disease activity index (SLEDAI) was 5.7 (±5.4). Fatigue was assessed by the Fatigue Severity Scale (FSS) and CBF by Tc-99m-hexamethyl propylamine oxime (HMPAO)-SPECT. The images were read and processed quantitatively by a computer program using the primary visual cortex as reference region and > 15% CBF deviation as definition of abnormality.
Results
The mean FSS score was 4.6 (±1.8). SPECT revealed focal CBF disturbances in 17 patients (30.4 %). Generalized symmetrical CBF reductions were present in 32 patients (57.1 %). There were no significant associations between CBF disturbances in any region of the brain and the degree of fatigue.
Conclusions
Fatigue in SLE patients is not related to focal or general CBF disturbances. Therefore, factors that do not influence blood flow seem responsible for the fatigue phenomenon. 相似文献