首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.

Aim

The aim of the study was to compare aerobic and anerobic abilities of prepubertal children and adults with the critical power concept.

Methods

Sixteen children (10.3 ± 0.9 years) and 15 adults (23.5 ± 3.6 years) performed five tests: a maximal-graded test and four constant load exercises until exhaustion. Critical power (CP) and anaerobic-work capacity (CTA) were determined from the power-1/time (P-t) linear relationship.

Results

Determination coefficients for P-t were 0.94 ± 0.05 in children and 0.96 ± 0.04 in adults. PC values were significantly (p < 0.01) lower in children (2.7 ± 0.4 W/kg) than in adults (3.1 ± 0.3 W/kg). CTA values were significantly (p < 0.001) lower in children (136.4 ± 50.8 J/kg) than in adults (247.1 ± 45.7 J/kg).

Conclusion

Satisfying determination coefficients for CP and CTA were found in children and adults. Children have a lower CP and CTA than adults. This result is in accordance with literature.  相似文献   

2.

Subject

The use of Fourier transform infrared spectrometry technique (FT-IR) as a pitch technique of the biological control of short and intense exercises close to those of Rugby matches.

Material and method

In reference to 28 rugbymen of international level, the biological results of three short and intense exercises and two periods of recovery were analyzed by TF-IR. The exercises are: (1) sprints; (2) 12 × 20 m of swerve running; (3) 6 × 30 s of shuttle run.

Results

Lactate, glucose, urea, and to a lesser degree, triglycerides showed a significant evolution. If the evolution of the two first was in conformity with the literature, the increase of urea probably results from the activation of the purins–nucleotides cycle, whereas the evolution of triglycerides is explained by their probable muscular use during periods of active recovery. Among proteins related to the healthy sportsman, only haptoglobin presents a significant variation difficult to explain whereas CRP, orosomucoid and immunoglobulins A, G and M remain close to their rest values.

Conclusion

With the use of FT-IR technique, it is possible to intervene directly on the pitches of the sporting practice to control the biological incidences and to adjust the loads individually. It is also possible to detect inflammatory and immunological problems related to the biomechanical and physiological stresses.  相似文献   

3.

Purpose

The aim of this study was to assess the timing of muscle activation during the acceleration phase of topspin forehand drives in young tennis players.

Synthesis

The activity of six muscles was recorded using surface electromyography during topspin forehand drives in 22 players (9–17 years). The timing of muscle activation was characterized by the onset of EMG bursts during the acceleration stage.

Conclusion

The proximal-to-distal sequential muscle activity was observed for the agonist muscles while the antagonist muscles were recruited at the end of the acceleration stage. This sequential muscle activity was common to all participants whatever their abilities.  相似文献   

4.

Introduction

The impact of resistance exercise on the growth of the vastus lateralis was assessed through interstitial microdialysis measurement of free Insulin-like Growth Factor-I at +3 h30, +4 h50 and +6 h after exercise in 4 healthy subjects.

Results

We observed 3 h30 after exercise an interstitial increase in 3 over 4 subjects, and thereafter a progressive decrease. In the mean time, free or total plasma concentrations did not change.

Conclusion

Resistance exercise seemed to induce an early increase of muscle interstitial free Insulin-like Growth Factor-I in order to initiate muscle growth by an autocrine – paracrine way.  相似文献   

5.

Objective

The aims of this review are to describe the main characteristics for the CT diagnosis of isolated caecal ischaemia (ICA) and give details of the differential diagnosis with other conditions with a similar clinical picture.

Material and methods

A retrospective study was conducted to review the CT findings of 4 patients diagnosed with ICA in our hospital. The parameters recorded to analyse their characteristics in the CT were: maximum thickness of the caecum wall, the appearance of the peri-caecum fat, presence of free fluid, signs of caecal or portal pneumatosis, the appearance of the caecal appendix, and general signs of the presence of vasculopathy.

Results

In all cases it was recorded that there was a thickening of the walls of the blind loop with an abrupt transition between the caecal wall and the walls of the ascending colon wall. In all cases the caecal thickening had a characteristic image in the central area. Signs of caecal pneumatosis were observed in two cases. All of them had an appendix with normal characteristics.

Conclusions

The combination of caecal wall thickening with oedematous characteristics, with no changes in the appendix, ileum and colon, suggest the diagnosis of caecal ischaemia, particularly with the presence of pneumatosis.  相似文献   

6.

Objectives

To evaluate the recanalization rate and clinical outcome three months after endovascular treatment for vertebrobasilar occlusion before the placement of stentrievers.

Material and methods

We reviewed all cases of basilar thrombosis treated with endovascular techniques at our center. We reviewed the clinical outcomes with the main objective of determining the recanalization rate and the secondary objective of evaluating the outcome using the modified Rankin scale (mRS) three months after treatment. We assessed clinical and angiographic variables and correlated them with outcome and complications.

Results

We reviewed a total of 27 consecutive patients (mean age, 58.1 ± 15.5 y; median National Institutes of Health Stroke Scale (NIHSS), 21, interquartile range, 18-29; median Glasgow coma score (GCS) 7, interquartile range, 4-9.5). The mean time between the onset of symptoms and endovascular treatment was 26.3 ± 41.7 hours. Complete or partial recanalization was achieved in 23 (85.1%) patients. Three months after treatment, 16 (59.2%) had died and 6 (22.2%) had good outcome (mRS ≤ 2).

Conclusion

Endovascular treatment achieved a high rate of recanalization of occlusions of the basilar artery. Nevertheless, a high percentage of the patients did not have a good outcome. New materials might improve the prognosis in these patients.  相似文献   

7.

Introduction

The objective of the study is to measure the evolution of the anthropometric and physical parameters in young elite rugby players during one rugby league season.

Results

This study shows an enhancement of the aerobic and lactic anaerobic performances in the first six months of the preparation. Therefore, these aptitudes decrease in April. There is no modification of the lactic anaerobic performance during the season.

Conclusion

This study shows the difficulty to organise the training planification during the winter period for the elite players. The reason for the rugby league season fatigue has yet to be defined and will be the purpose of a future study.  相似文献   

8.
9.

Aim

To study the relationship between the five-jump test (5JT) performance, 30 m sprint test and vertical jump performances.

Synthesis of facts

Thirteen male soccer players (15–16 years olds) performed the following tests: 5JT, 30 m sprint and 3 vertical jumps: SJ, CMJ and Free CMJ. The 5JT was strongly correlated with 30 m sprint (R = 0.83; P < 0.01), the SJ (R = 0.71; P < 0.01), the CMJ (R = 0.84; P < 0.01) and the free CMJ (R = 0.62; P < 0.05). The 5JT is also correlated with the index of explosiveness (R = 0.93; P < 0.01).

Conclusion

The 5JT can be used to evaluate muscular strength and explosivity of lower limbs in young soccer players.  相似文献   

10.

Objective

To review and classify the interval cancers found in the Principality of Asturias's Breast Cancer Screening Program (PDPCM). A secondary objective was to determine the histological characteristics, size, and stage of the interval cancers at the time of diagnosis.

Material and methods

We included the interval cancers in the PDPCM in the period 2003-2007. Interval cancers were classified according to the breast cancer screening program protocol, with double reading without consensus, without blinding, with arbitration. Mammograms were interpreted by 10 radiologists in the PDPCM.

Results

A total of 33.7% of the interval cancers could not be classified; of the interval cancers that could be classified, 40.67% were labeled true interval cancers, 31.4% were labeled false negatives on screening, 23.7% had minimal signs, and 4.23% were considered occult. A total of 70% of the interval cancers were diagnosed in the year of the period between screening examinations and 71.7% were diagnosed after subsequent screening. A total of 76.9% were invasive ductal carcinomas, 61.1% were stage II when detected, and 78.7% were larger than 10 mm when detected.

Conclusions

The rate of interval cancers and the rate of false negatives in the PDPCM are higher than those recommended in the European guidelines. Interval cancers are diagnosed later than the tumors detected at screening. Studying interval cancers provides significant training for the radiologists in the PDPCM.  相似文献   

11.

Aims

Authors report their personal experience on the surgical treatment of repeated anterior shoulder dislocations, using an anterior bone block in accordance with the procedure suggested by Didier Patte.

Results

From the year 1988 and during 10 years, 35 patients suffering from repeated anterior shoulder dislocations were surgically treated by this procedure. It was appropriate to retrospectively review the clinical and functional outcomes after Patte repair for recurrent anterior glenohumeral instability. The mean follow-up was approximately 10 years, with a mean percentage of 75% for the observance. There was no recurrence after surgery. Moreover, 88% of patients had good outcomes, according to the scale suggested by Butel et al., with total resumption of work and physical activities. The occurrence of chronic complication such as osteoathrosis was scarce (only one case for the series), while 20% of subjects showed apprehension during some specific shoulder movements.

Conclusion

In order to expect best functional outcomes, the choice of the surgical procedure should take into account the extent of initial injury. Considering these ground requirements, the Patte procedure seems to provide very satisfactory long-term functional outcomes.  相似文献   

12.

Objectives

To evaluate the sensation of pleasantness perceived by patients attended in the radiology department in response to decorative elements hung on the walls in the waiting rooms and in the hallways of the imaging area.

Material and methods

The material resources comprised works of art in the form of “magic windows” representing scenes from nature installed on the ceilings and walls of the waiting area and hallways of the imaging area. Patients were given a brief questionnaire with general data and questions (sadness-cheerfulness, coldness-warmth, darkness-light, and pessimism-optimism) about their perception of the decorative elements.

Results

Of the 150 questionnaires collected, 142 were filled out correctly. The overall health of these patients was good in 84 (56%), not bad in 58 (39%), and poor in 8 (5%). The idea seemed very good to 70 patients (47%), good to 58 (39%), not bad to 8 (5%), indifferent to 11 (7%), bad to 1 (1%), and very bad to 2 (1%). As far a patients’ mobility, 119 patients (79%) walked into the department, 18 (12%) were wheeled in on beds, and 13 (9%) needed wheelchairs.

Conclusions

We found a high level of satisfaction with the decorative elements.  相似文献   

13.

Introduction

The aim of the study is to assess the psychological effects of a short-term therapeutical prednisolone intake.

Synthesis

We studied, according to a double-blind, randomized cross-over protocol, the effects of a seven day prednisolone intake (60 mg/day) in 10 healthy male subjects on global health and mood state. No significant change was found between the treatments (prednisolone/placebo) in the 15 variables investigated. However, tendencies appeared revealing an increase of self-esteem, personal accomplishment and athletic identification, as well as a decrease in negative affect for the subjects under treatment.

Conclusion

These results could reveal a psychological impact of glucocorticoid intake and should be confirmed by a further study with athletes submitted to a more intense physical activity.  相似文献   

14.

Aim

This review is aimed to synthesize current scientific knowledge on the part played by physical activity in prevention and treatment of the paediatric obesity.

Current

The physical activity (and inactivity?) is unanimously recognized like an essential element of the fight against the obesity increase in children and adolescents. In the treatment the last meta-analysis and literature reviews confirm that the best strategy is the reduction of the sedentary behaviours, the increase in the physical activity associated with an education and restriction nutritional. On the other hand, the part played by the physical activity in the prevention interventions although not discussed, must be specified in its association with other elements such as nutritional education according to the age, of the obesity level… The physical activity practice as of the youth is to be associated an early tracking factor of risk. The recommendations of physical activity must be adapted to the required objective and the possibilities physical, physiological, sociological… of the subjects.

Conclusion

Although characteristics of the physical activity to prescribe for each specific objective; prevention, loss of or not taken again body mass weight, remain to be specified for the child and the teenager, an active way of life is one of the major factors of the fight against the increase in the prevalence of obesity.  相似文献   

15.

Aims

To estimate the interest of a scientific approach in the improvement of the performance in the collective sports.

Current knowledge

The coach is seeking permanent optimal performance for his team. In this context, rugby and handball have experienced a development of the scientific approach is very different. The handball, as a young sport, has benefited almost immediately with a scientific approach. Rugby has over him, has developed this approach by chance, for historical reasons rather based on aggressiveness growing contacts and safeguarding of players. In addition, a scientific culture has witnessed a major interest with the increase in the number of hours of practice and then with the advent of professionalism. It was necessary to evaluate, manage and improve the performance of athletes, followed establish accurate to assume this workload. Scientific studies have contributed to these changes.

Conclusion

What steps or processes should help scientists better understand the issue of seeking permanent progress. However, it is important to retain a central priority technical training and tactical player without stopping his creativity.  相似文献   

16.

Objective

We used an animal model to analyze the reproducibility and accuracy of certain biomarkers of bone image quality in comparison to a gold standard of computed microtomography (μCT).

Material and methods

We used magnetic resonance (MR) imaging and μCT to study the metaphyses of 5 sheep tibiae. The MR images (3 Teslas) were acquired with a T1-weighted gradient echo sequence and an isotropic spatial resolution of 180 μm. The μCT images were acquired using a scanner with a spatial resolution of 7.5 μm isotropic voxels. In the preparation of the images, we applied equalization, interpolation, and thresholding algorithms. In the quantitative analysis, we calculated the percentage of bone volume (BV/TV), the trabecular thickness (Tb.Th), the trabecular separation (Tb.Sp), the trabecular index (Tb.N), the 2 D fractal dimension (D2D), the 3 D fractal dimension (D3D), and the elastic module in the three spatial directions (Ex, Ey and Ez).

Results

The morphometric and mechanical quantification of trabecular bone by MR was very reproducible, with percentages of variation below 9% for all the parameters. Its accuracy compared to the gold standard (μCT) was high, with errors less than 15% for BV/TV, D2D, D3D, and Eappx, Eappy and Eappz.

Conclusions

Our experimental results in animals confirm that the parameters of BV/TV, D2D, D3D, and Eappx, Eappy and Eappz obtained by MR have excellent reproducibility and accuracy and can be used as imaging biomarkers for the quality of trabecular bone.  相似文献   

17.

Introduction

The purpose of this study was to investigate the validity and reliability of an inertial dynamometer using accelerometry.

Methods

Fourteen subjects were tested during three successive sessions at four increasing loads (30, 50, 70 and 95% of the 1RM). Maximal force, velocity and power performances were simultaneously assessed by the Myotest (Myotest S.A., Switzerland), an inertial dynamometer using accelerometry, and by another control valid dynamometer witch combine accelerometer and linear position transducer. At three first loads, only minor differences appeared in between both dynamometers, correlations were excellent and coefficients of variation were good and similar. However, at 95% of the 1RM, Myotest validity and reliability became insufficient.

Conclusion

Bench press inertial assessment with accelerometer appeared valid and reliable at 30, 50 and 70% of the 1RM, but not at 95% of the 1RM.  相似文献   

18.

Backgroung

Previous studies showed that maximal oxygen uptake and maximal heart rate were not different during prolonged fasting (ramadan) compared to normal feeding period. However, the effect of ramadan on the blood pressure response during incremental exercise has not been investigated.

Objective

This study aimed to evaluate the evolution of blood pressure during incremental trial in ramadan period.

Methods

Twelve young trained male aged 24 ± 4 yrs participated as voluntary subjects. Their anthropometric parameters, maximal aerobic power and maximal heart were measured in fasting and in normal feeding periods during incremental trial on cycle ergometer.

Results

No significant difference was observed in any anthropometric parameter. Maximal aerobic power of fasting period was significantly less (P < 0,05) compared to normal feeding. Heart rate at rest, at maximal exercise and during a 15 min period of recovery was not significantly affected. Systolic blood pressure of fasting period at maximal power was significantly lower than during the control period (P < 0,05).

Conclusion

Ramadan negatively influences the capacity of maximal power and cardiovascular response at maximal power.  相似文献   

19.

Introduction

The maximal running velocity (VIFT) reached at the end of the 30-15 Intermittent Fitness Tests (30-15IFT) is very well related to most physiologic determinants of team-sport performance: explosive power of lower limbs, speed, maximal aerobic power and the ability to recover between exercise bouts. Nevertheless, its relationship with repeated sprint ability (RSA) was unknown.

Synthesis of the facts

Present results in 84 team-sport athletes show that VIFT is very well related to mean sprint time during a RSA test (p > 0.001).

Conclusion

We conclude that VIFT is highly representative of most physiologic determinants of performance in team-sports, and could thus been used to monitor athletic performance of team-sport players.  相似文献   

20.

Introduction

The muscle oxygenation profile determined with the technique of near infrared spectroscopy was used to assess the muscle oxygen utilization kinetics at the onset of exercise.

Synthesis

The mean response time of the muscle deoxygenation increase was not modified by hyperoxia (19.6 ± 2.3 s in hyperoxia versus 20.6 ± 2.8 s in normoxia, NS).

Conclusion

This result suggests that hyperoxia did not induce any acceleration of the oxygen utilization kinetic at the muscle level and that the oxygen delivery to muscle is not the limiting factor of this kinetic.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号