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The purpose of the present study was to investigate the effects of 6 weeks strength vs. ballistic-power (Power) training on shot put throwing performance in novice throwers. Seventeen novice male shot-put throwers were divided into Strength (N = 9) and Power (n = 8) groups. The following measurements were performed before and after the training period: shot put throws, jumping performance (CMJ), Wingate anaerobic performance, 1RM strength, ballistic throws and evaluation of architectural and morphological characteristics of vastus lateralis. Throwing performance increased significantly but similarly after Strength and Power training (7.0-13.5% vs. 6.0-11.5%, respectively). Muscular strength in leg press increased more after Strength than after Power training (43% vs. 21%, respectively), while Power training induced an 8.5% increase in CMJ performance and 9.0 - 25.8% in ballistic throws. Peak power during the Wingate test increased similarly after Strength and Power training. Muscle thickness increased only after Strength training (10%, p < 0.05). Muscle fibre Cross Sectional Area (fCSA) increased in all fibre types after Strength training by 19-26% (p < 0.05), while only type IIx fibres hypertrophied significantly after Power training. Type IIx fibres (%) decreased after Strength but not after Power training. These results suggest that shot put throwing performance can be increased similarly after six weeks of either strength or ballistic power training in novice throwers, but with dissimilar muscular adaptations.

Key points

  • Ballistic-power training with 30% of 1RM is equally effective in increasing shot put performance as strength training, in novice throwers, during a short training cycle of six weeks.
  • In novice shot putters with relatively low initial muscle strength/mass, short-term strength training might be more important since it can increase both muscle strength and shot put performance.
  • The ballistic type of power training resulted in a significant increase of the mass of type IIx muscle fibres and no change in their proportion. Thus, this type of training might be used effectively during the last weeks before competition, when the strength training load is usually reduced, in order to increase muscle power and shot put performance in novice shot putters.
Key words: Shot put, muscle fibres, ultrasound, ballistic training, muscle mass.  相似文献   
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For the decade 2000–2010, suicidal rates appear to be both low and stable in Greece and unrelated to the socioeconomic environment. It is highly possible that the recent crisis caused a significant increase in dysphoria, stress, depression and maybe suicidal ideation in the general population, but completed suicides do not seem to have increased so far. Measures are needed to make sure there will be no increase in completed suicides in the near future, since historically, periods of socioeconomic instability might be related to increased suicidality. Community interventions reduce stigma and enhance help-seeking. However, only those including the creation of social support networks are essential in the fight against suicidality.  相似文献   
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PurposeTo evaluate the clinical outcome after CT-guided interstitial high-dose-rate (HDR) brachytherapy for dose escalation in the radiotherapy treatment of inoperable locally advanced non–small-cell lung cancer (NSCLC).Methods and MaterialsFrom 2005 to 2015, 16 patients with unresectable NSCLC were treated. Median age was 65.7 years (range, 52–86). The median tumor volume was 95.3 cm3 (range, 20.0–2000.0). The median prescribed HDR was 15.0 Gy (range, 7.0–32.0) delivered in twice-daily fractions of 6.0–8.0 Gy in 4 patients and in once-daily fractions of 7.0–15.0 Gy in 12 patients, respectively.ResultsAfter a median followup of 12.5 months, median overall survival and local control was 12.9 and 24.9 months, respectively. The corresponding median overall survival and local control rates at 1, 2, and 3 years were 56.2%, 37.5%, and 12.5% as well as 68.9%, 57.4%, and 43%, respectively. Apart from one Grade 1 cough episode persisting for 1 week and one patient developing a minor hemopneumothorax requiring no postprocedural drainage, no other adverse events were recorded.ConclusionsCT-guided interstitial HDR brachytherapy is a safe modality for radiation dose escalation which may play a role in the definitive radiotherapy treatment of locally advanced NSCLC.  相似文献   
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European Archives of Psychiatry and Clinical Neuroscience - Advanced parental age at delivery and neurological soft signs (NSS) constitute risk factors for schizophrenia. The aim of the current...  相似文献   
129.
Idiopathic normal pressure hydrocephalus is a hydrodynamic disorder whose etiology remains unclear. The diagnosis is mainly clinical and the traditional treatment is cerebrospinal fluid shunt diversion. With the introduction of modern management strategies, endoscopic third ventriculostomy has become a viable alternative to shunting and constitutes a well-established method of treatment for obstructive hydrocephalus. The new hydrodynamic concept of hydrocephalus suggests that endoscopic third ventriculostomy (ETV) may be an effective treatment for communicative hydrocephalus. In our current review, the authors focus on the up-to-date knowledge regarding the consideration of endoscopic third ventriculostomy as a safe surgical option in the management of idiopathic normal pressure hydrocephalus.  相似文献   
130.
Objective: The purpose of this retrospective observational cohort study was to determine the impact of certain risk factors on fetal loss, after mid-trimester amniocentesis.

Material and methods: Six thousand seven-hundred and fifty-two (6752) consecutive amniocenteses with known pregnancy outcome performed during a 7-year period (2004–2010) were included in this study. Different maternal-, fetal- and procedure-related factors were evaluated in this study.

Results: During this 7-year period, 6752 cases who underwent amniocentesis, with complete data available were evaluated for the outcome and risk factors mentioned. Total fetal loss rate (FLR) up to the 24th week was 1.19%. Risk factors associated with increased risk of fetal loss after amniocentesis were maternal age (OR:2.0), vaginal spotting (OR:2.2) and serious bleeding (OR:3.5) during pregnancy, history of 2nd trimester termination of pregnancy (OR:4.0), history of more than three spontaneous (OR:3.0) or surgical first trimester abortions (OR:2.1), fibromas (OR:3.0) and stained amniotic fluid (OR:6.1).

Conclusions: Amniocentesis is a safe-invasive procedure for prenatal diagnosis with total FLR of 1.19% in our institution during the study period. The present study has emphasized the significance of certain risk factors for adverse outcome and therefore the need to individualize the risk.  相似文献   
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