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Sports experts represent a population of people who have acquired expertise in sports training and competition. Recently, the number of studies on sports experts has increased; however, neuroanatomical changes following extensive training are not fully understood. In this study, we used cortical thickness measurement to investigate the brain anatomical characteristics of professional divers with extensive training experience. A comparison of the brain anatomical characteristics of the non-athlete group with those of the athlete group revealed three regions with significantly increased cortical thickness in the athlete group. These regions included the left superior temporal sulcus, the right orbitofrontal cortex and the right parahippocampal gyrus. Moreover, a significant positive correlation between the mean cortical thickness of the right parahippocampal gyrus and the training experience was detected, which might indicate the effect of extensive training on diving players' brain structure. 相似文献
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Laudner KG 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(3):672-676
Injuries stemming from shoulder instability are very common among athletes participating in contact sports, such as football. Previous research has shown that increased laxity negatively affects the function of the sensorimotor system potentially leading to a pathological cycle of shoulder dysfunction. Currently, there are no data detailing such effects among football players. Therefore, the purpose of this study was to examine the differences in upper extremity sensorimotor control among football players compared with that of a control group. Forty-five collegiate football players and 70 male control subjects with no previous experience in contact sports participated. All the subjects had no recent history of upper extremity injury. Each subject performed three 30-second upper extremity balance trials on each arm. The balance trials were conducted in a single-arm push-up position with the test arm in the center of a force platform and the subjects' feet on a labile device. The trials were averaged, and the differences in radial area deviation between groups were analyzed using separate 1-way analyses of variance (p < 0.05). The football players showed significantly more radial area deviation of the dominant (0.41 ± 1.23 cm2, p = 0.02) and nondominant arms (0.47 ± 1.63 cm2, p = 0.03) when compared with the control group. These results suggest that football players may have decreased sensorimotor control of the upper extremity compared with individuals with no contact sport experience. The decreased upper extremity sensorimotor control among the football players may be because of the frequent impacts accumulated during football participation. Football players may benefit from exercises that target the sensorimotor system. These findings may also be beneficial in the evaluation and treatment of various upper extremity injuries among football players. 相似文献
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In order to evaluate the significance of injecting vitamins complexes and stimulants minutes before soccer games and its role in spread of hepatitis C virus (HCV) we interviewed and tested 40 ex-soccer players, who played professionally in Mato Grosso, Brazil, between 1970 and 1989. Five players were found anti-HCV positive with enzyme-immunoassay. When re-tested by immunoblot (RIBA), three of these five were confirmed to be positive reacting. The anti-HCV positivity (7.5%) was higher than usually found among blood donors (0.9%) in this region (p < 0.01). None of the players had had prior history of any risk factor that might indicate HCV exposure. We suggest that the common practice of soccer players in the inner part of Brazil in the 70's and 80's, to receive fortifying injections, often with shared syringes, may place ex-soccer players in a potential risk group for HCV infection and warrants further investigation and attention by public health workers. 相似文献
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We compared workplace injuries between young (16 to 19 years of age) and adult workers using West Virginia Workers' Compensation database. All workers injured between January 1 and December 31, 1995 were included in the analysis. The industry-specific injury incidence rates between young and adults workers were significantly different with lower rates of injury in young workers in all sectors except service sector. In the service sector the young workers had significantly higher injury rates than adults (rate ratios for young workers were 2.28, 1.92, and 2.94 when compared with age groups 20-24, 25-34, and >34, respectively). Estimates of the proportional injury ratio (PIR) indicated significantly greater risk of finger (PIR 1.62) and hand (PIR 1.66) injuries and burns (PIR 3.27) and lacerations (PIR 1.69) in the young workers. The proportion of injuries occurring in the summer months was higher in the young than in the adults (35.2% vs. 27.0%), particularly in the service sector (79.6% vs. 25.9%). Higher injury rates in young workers compared to adults in the service sector may be explained by the seasonal employment of young workers in West Virginia. 相似文献
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M Grabara 《Biology of sport / Institute of Sport》2015,32(1):79-85
Due to high training loads and frequently repeated unilateral exercises, several types of sports training can have an impact on the process of posture development in young athletes. The objective of the study was to assess and compare the postures of adolescent male volleyball players and their non-training peers. The study group comprised 104 volleyball players while the control group consisted of 114 non-training individuals aged 14-16 years. Body posture was assessed by the Moiré method. The volleyball players were significantly taller, and had greater body weight and fat-free mass. The analysis of posture relative to symmetry in the frontal and transverse planes did not show any significant differences between the volleyball players and non-athletes. Postural asymmetries were observed in both the volleyball players and the control participants. Lumbar lordosis was significantly less defined in the volleyball players compared to non-training individuals while no difference was observed in thoracic kyphosis. All athletes demonstrated a loss of lumbar lordosis and an increase in thoracic kyphosis. Significant differences in anteroposterior curvature of the spine between the volleyball players and the non-athletes might be associated with both training and body height. Considering the asymmetric spine overloads which frequently occur in sports training, meticulous posture assessment in young athletes seems well justified. 相似文献
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Rhea MR Oliverson JR Marshall G Peterson MD Kenn JG Ayllón FN 《Journal of strength and conditioning research / National Strength & Conditioning Association》2008,22(1):230-234
Exercise professionals seeking to develop evidence-based training programs rely on several training principles demonstrated through research and professional experience. In an effort to further research examining these principles, an investigation was designed and completed to evaluate the compatibility of cardiovascular endurance and neuromuscular power training. Sixteen Division-I collegiate baseball players were divided into two training groups with lower body power measured before and after their college playing season. The two groups differed in training in that one group performed moderate- to high-intense cardiovascular endurance training 3-4 days per week throughout the season, while the other group participated in speed/speed endurance training. A significant difference between groups (P < .05) was identified in the change in lower body power during the baseball season. During the season, the endurance training group decreased an average of 39.50 +/- 128.03 watts while the speed group improved an average of 210.63 +/- 168.96 watts. These data demonstrate that moderate- to high-intense cardiovascular endurance and neuromuscular power training do not appear to be compatible when performed simultaneously. For baseball players, athletes who rely heavily on power and speed, conventional baseball conditioning involving significant amounts of cardiovascular endurance training should be altered to include more speed/power interval training. 相似文献
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C. Collet R. Roure G. Delhomme A. Dittmar H. Rada E. Vernet-Maury 《European journal of applied physiology and occupational physiology》1999,80(1):41-51
Complex motor skills require planning and programming before execution. The autonomic nervous system (ANS) is thought to transcribe these central operations at the peripheral level: a motor act is thought to be simultaneously programmed by central and autonomic nervous structures. The aim of this study was to verify that autonomic responses reflect the quality of central motor programming leading to successful or failed performance when subjects are required to perform a complex motor skill. The specificity of the ANS response has already been demonstrated through direct recording from sympathetic fibres. It has also been demonstrated through several mental tasks and closed motor skills such as shooting: ANS responses have been shown to be capable of distinguishing success from failure. The aim of this experiment was to test whether ANS responses are capable of distinguishing two levels of achievement during the performance of a skill involving uncertainty (open skill). The subjects had to intercept a ball on a volleyball court, using the forearm receive and pass technique, in order to pass it on to a moving human target. The results were displayed in terms of accuracy: accurate passes were successful and inaccurate passes missed the target. Six autonomic variables were recorded simultaneously during the task: skin resistance and potential, skin blood flow and temperature, instantaneous heart rate and respiratory frequency. Results showed that autonomic variables were capable of distinguishing success from failure in 22 subjects out of 24. This made it possible to build up autonomic patterns characterising subjects' performances, and to confirm that autonomic functioning may reveal information processing in the central nervous system. Thus, the study of autonomic responses may constitute an inferential model of central nervous system functioning. Such a method could be used as an index for the control of mental preparation. 相似文献
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Manu Raj Mathur Richard G. Watt Christopher J. Millett Priyanka Parmar Georgios Tsakos 《PloS one》2015,10(10)
Objectives
To assess socioeconomic inequalities in traumatic dental injuries (TDIs) in adolescents in New Delhi and examine the role of material, psychosocial and behavioural factors in explaining these inequalities.Methods
We conducted a cross sectional study of 1386 adolescents aged between 12–15 years residing in three diverse areas of New Delhi. A non-invasive clinical examination was used to estimate the prevalence of TDIs, and an interviewer-administered questionnaire was used to gather relevant behavioural and socio-demographic data. Multiple logistic regression models were used to assess the association between area based socioeconomic position and TDIs.Results
The overall prevalence of TDIs was 10.9%. Social inequalities in the prevalence of TDIs were observed across the adolescent population according to their area of residence. Socio-economic group differences in the prevalence of TDIs remained statistically significant after adjusting for demographic factors, material resources, social capital, social support and health affecting behaviours (OR 3.36, 95% CI 1.75–6.46 and OR 3.99, 95% CI 1.86–8.56 for adolescents from resettlement areas and urban slums respectively in comparison to middle class adolescents). Different psychosocial, material and socio-demographic variables did not attenuate the estimates for the relationship between area socioeconomic position and TDIs.Conclusion
Area of residence was a strong predictor of TDIs in adolescents with a higher prevalence in more deprived areas. Social inequalities in TDIs were not explained by psychosocial and behavioural variables. Health promoting policies aimed at improving the physical environment in which adolescents reside might be instrumental in reducing the prevalence of TDIs and associated inequalities. 相似文献10.
Aşçi A Açikada C 《Journal of strength and conditioning research / National Strength & Conditioning Association》2007,21(1):10-16
The purpose of this study was to compare 1 repetition maximum (1RM) strength, maximum power (MP), linear momentum (Mp), and the loads of 1RM responsible for maximum power (MP%) and for linear momentum (Mp%) generated in explosive concentric bench press (CBP) motion among athletes from different sports. A total of 56 athletes (13 sprinters, 16 basketball players, 16 handball players, 5 volleyball players, and 6 bodybuilders) performed CBP in the loads of 40, 50, 60, 70, and 80% of 1RM with 1-minute rest intervals. MP and Mp were assessed during CBP by customized apparatus with 3 separate displacement transducers. There were no significant differences in MP, Mp, MP%, and Mp% among the athletes. The only significant positive correlation was found between overall 1RM and Mp for athletes (r = 0.37). In conclusion, long-term sport-specific training adaptations do not play a major role on speed-strength parameters in athletes with similar strength from different sports backgrounds. 相似文献
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Carolyn Emery Jian Kang Ian Shrier Claude Goulet Brent Hagel Brian Benson Alberto Nettel-Aguirre Jenelle McAllister Willem Meeuwisse 《CMAJ》2011,183(11):1249-1256
Background:
In a previous prospective study, the risk of concussion and all injury was more than threefold higher among Pee Wee ice hockey players (ages 11–12 years) in a league that allows bodychecking than among those in a league that does not. We examined whether two years of bodychecking experience in Pee Wee influenced the risk of concussion and other injury among players in a Bantam league (ages 13–14) compared with Bantam players introduced to bodychecking for the first time at age 13.Methods:
We conducted a prospective cohort study involving hockey players aged 13–14 years in the top 30% of divisions of play in their leagues. Sixty-eight teams from the province of Alberta (n = 995), whose players had two years of bodychecking experience in Pee Wee, and 62 teams from the province of Quebec (n = 976), whose players had no bodychecking experience in Pee Wee, participated. We estimated incidence rate ratios (IRRs) for injury and for concussion.Results:
There were 272 injuries (51 concussions) among the Bantam hockey players who had bodychecking experience in Pee Wee and 244 injuries (49 concussions) among those without such experience. The adjusted IRRs for game-related injuries and concussion overall between players with bodychecking experience in Pee Wee and those without it were as follows: injury overall 0.85 (95% confidence interval [CI] 0.63 to 1.16); concussion overall 0.84 (95% CI 0.48 to 1.48); and injury resulting in more than seven days of time loss (i.e., time between injury and return to play) 0.67 (95% CI 0.46 to 0.99). The unadjusted IRR for concussion resulting in more than 10 days of time loss was 0.60 (95% CI 0.26 to 1.41).Interpretation:
The risk of injury resulting in more than seven days of time loss from play was reduced by 33% among Bantam hockey players in a league where bodychecking was allowed two years earlier in Pee Wee compared with Bantam players introduced to bodychecking for the first time at age 13. In light of the increased risk of concussion and other injury among Pee Wee players in a league where bodychecking is permitted, policy regarding the age at which hockey players are introduced to bodychecking requires further consideration.Rates of participation in youth-level ice hockey are high in North America.1,2 There is growing concern regarding the impact of concussion in this population.3–5 Body-checking is the reported mechanism for 45%–86% of injuries in youth ice hockey.5–11 Internationally, the age group at which bodychecking is introduced varies. In Canada, bodychecking is introduced in Pee Wee leagues (ages 11–12 years), except in the province of Quebec, where it is introduced in Bantam (ages 13–14).12The age at which bodychecking should be introduced is controversial. We recently reported that the risk of injury and concussion in a Pee Wee league that allows bodychecking was more than threefold higher than in a Pee Wee league that does not allow bodychecking.9 Findings from systematic reviews support these findings.13,14Injury rates may increase when players begin to learn bodychecking, because it is a new skill. If so, injury rates would be expected to be higher among players without bodychecking experience in Pee Wee (i.e., those in Quebec) than among players introduced to body-checking two years earlier in Pee Wee (e.g., in Alberta). We examined whether the risk of concussion and other injury among hockey players in Bantam leagues differed between players with and those without bodychecking experience in Pee Wee. 相似文献13.
Z. B. Belotserkovskii B. G. Lyubina A. V. Smolenskii V. V. Sagitova O. V. Kozyreva E. V. Bogdanova 《Human physiology》2007,33(4):490-495
The structural and functional characteristics of the heart of 51 retired soccer players who ceased training 3–15 years ago are presented. A number of structural and functional signs of “athlete’s heart” detected in the subjects indicate more efficient heart functioning at rest and during exercise. The myocardium requires less oxygen per unit power of muscle work, and each gram of the myocardium of retired athletes performs more mechanical work than the myocardium of untrained subjects of the same age. This indicates long-term adaptation of the heart of retired athletes to muscle work. The heart functioning at rest and during exercise in retired athletes becomes less efficient with age, this trend being more pronounced in older former athletes than in younger ones. This is expressed in an increased oxygen consumption by the myocardium, a higher occurrence of atypical electrocardiogram patterns, age-related changes in myocardial contractility, and a decreased capacity of each gram of the myocardium for generating mechanical work. 相似文献
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Injuries and deaths associated with off-road recreational vehicles are of increasing concern in North America. We reviewed all hospital admissions and deaths attributed to these vehicles in Manitoba from April 1979 to April 1985 among children 16 years of age or younger. Of the 693 hospital admissions and deaths 480 were associated with motorbikes, snowmobiles or all-terrain vehicles (ATVs). The incidence of injuries resulting from snowmobile and dirtbike accidents remained stable over the study period; however, there was an almost exponential increase in the number of admissions because of ATV-related injuries. There were 21 deaths during the study period. Preventive measures through legislation are necessary to reduce the numbers of injuries and deaths; these include mandatory registration, licensing and enhanced safety regulations. 相似文献
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Miller TA Thierry-Aguilera R Congleton JJ Amendola AA Clark MJ Crouse SF Martin SM Jenkins OC 《Journal of strength and conditioning research / National Strength & Conditioning Association》2007,21(1):48-51
Aerobic capacity and body composition were measured at 3 time points over a 1-year period in 26 Division 1A women soccer players from Texas A&M University, in order to determine whether there were seasonal changes in these parameters. Subjects were tested in December, immediately following a 4-month competitive season; in April, following 15 weeks of strength and conditioning; and immediately prior to the start of the regular season in August, following a 12-week summer strength and conditioning program. A periodized strength and conditioning program design was incorporated in order to optimize anaerobic and oxidative capacity immediately prior to the regular competitive season. Significant differences in VO2max were measured between August (49.24 +/- 4.38 ml x kg(-1) x min(-1)) and December (44.87 +/- 4.61 ml x kg(-1) x min(-1)). No significant changes in aerobic capacity were found between April (47.43 +/- 4.01 ml x kg(-1) x min(-1)) and August (49.64 +/- 5.25 ml x kg(-1) x min(-1)). Significant increases in body fat were measured between August (15.71 +/- 2.92%) and December (18.78 +/- 2.79%), before and after the competitive season, respectively. No significant changes in body fat were found between April (16.24 +/- 2.95%) and August (15.71 +/- 2.92%). The results of this study suggest that decreases in muscle mass over the course of a regular competitive season contribute to decreases in aerobic capacity in collegiate women soccer players. Although it is unknown whether this decrease in muscle mass is the result of inadequate training or a normal adaptation to the physiological demands imposed by soccer, the results of the current study suggest that resistance training volume should be maintained during the competitive season, in order to maintain preseason levels of muscle mass. 相似文献
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Frantz TL Ruiz MD 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(11):2985-2990
Debate exists between the benefits and effectiveness of a dynamic warm-up vs. a static warm-up. This study was conducted to compare dynamic and static warm-ups on lower body explosiveness as measured by stationary vertical jump (VJ) and standing long jump (LJ) among collegiate baseball players. Participants (n = 17; age = 19.59 ± 1.37 years) progressed through 3 different warm-ups on weekly testing dates over a 7-week period. After the warm-up routines, participants were measured for VJ height and LJ distance in centimeters. The mean jump heights for VJ were 66.49 ± 8.28 cm for dynamic, 61.42 ± 7.51 cm for static, and 62.72 ± 7.84 cm for the control condition. The mean jump distances for LJ were 231.99 ± 20.69 cm for dynamic, 219.69 ± 20.96 cm for static, and 226.46 ± 20.60 cm for the control. Results indicated that the participants jumped significantly higher in both experimental conditions while under the influence of the dynamic warm-up (VJ-F = 22.08; df = 1.33, 21.345; p < 0.00 and LJ-F = 32.20; df = 2, 32; p < 0.01). Additional LJ analysis determined that individuals jumped significantly further after no warm-up compared to after a static warm-up (-6.78, p < 0.05). Lower body explosiveness is critical in baseball and many other sports as well. The results show that dynamic warm-up increases both VJ height and LJ distance. Specifically, these findings indicate that athletes could gain nearly 2 in. on his or her vertical jump by simply switching from a static warm-up routine to a dynamic routine. 相似文献
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Aleksandra Krivograd Klemenčič Nataša Smolar-Žvanut Darja Istenič Tjaša Griessler-Bulc 《Biologia》2010,65(3):422-437
In 2005 and 2006, epiphyton samples were collected from seven lowland and montane peat bogs in Slovenia. Water temperature,
pH, conductivity, dissolved oxygen and saturation were measured at the same time. Diatoms, desmids and Cyanobacteria were
the most abundand groups in species number. Canonical Correspondence Analysis (CCA) was carried out on Cyanobacteria, diatom
and desmid flora composition. This analysis showed that shading was the most important parameter in Cyanobacteria distribution
and bedrock the most important one in that of diatoms and desmids. Cluster analyses were carried out based on the Cyanobacteria,
diatom and desmid data. The Cyanobacteria and diatom data separated sites, whereas the desmid data revealed a temporal aspect. 相似文献
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Mirjana Bistan Romana Marinšek Logar Tatjana Tišler 《Central European Journal of Biology》2011,6(5):829-837
Estrogenic activity has been detected in aquatic ecosystems across the world. However, there is a lack of such data for Slovenian
wastewaters and surface waters. The Slovenian monitoring program of effluents discharged into surface waters does not require
that emissions of natural and synthetic estrogens into aquatic environments be assessed and controlled. In our study, we assessed
the potential estrogenicity of wastewater samples from three wastewater treatment plants using a yeast estrogen screen assay
(YES assay). Due to the high inhibition of yeast growth in samples obtained during our first sampling period, it was impossible
to detect any estrogenic activity. An additional silica gel clean-up step reduced the toxicity of samples collected during
our second sampling period; as a result, we were able to record up to 95% relative estrogenic activity inhibition. Deconjugation
of the estrogens did not significantly influence our results. We detected estrogenic activity using a YES assay in almost
all influent and effluent samples tested, which suggests that the wastewater treatment plants (WWTPs) examined do not effectively
remove (xeno)estrogens from wastewaters. Our results suggest that a YES assay is an appropriate screening method for monitoring
estrogenic activity in effluents. However, prediction of the potential impacts of wastewater (xeno)estrogens on aquatic organisms
require additional in vitro and in vivo assays. 相似文献
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Gabriela Ilie Angela Boak Robert E. Mann Edward M. Adlaf Hayley Hamilton Mark Asbridge Jürgen Rehm Michael D. Cusimano 《PloS one》2015,10(9)