Made available in DSpace on 2016-06-02T19:22:10Z (GMT). No. of bitstreams: 1 5590.pdf: 896581 bytes, checksum: 8218562e6c917325ce14773f361afc96 (MD5) Previous issue date: 2011-09-15 / Financiadora de Estudos e Projetos / There are few data about the mercury influence on bone metabolism them it is important to investigate the bone parameters that can be affected by it. The aim of this study was to evaluate the biometric, physical, biomechanical and enzymatic (MMPs) bone alterations in adult rats contaminated with mercurous chloride (HgCl2) during their development. The animals were separated in 4 groups: 3, 6, 9 and 12 months. The animals received mercuric chloride (experimental group) and saline (control group) by stomach gavage. The treatment had begun on 30 days of animals life, 5 times a week during 60 days. The daily dose was 5mg/kg of body weight of HgCl2 and 0,1ml of saline /100g of body weight. The animals were weighted 3 times a week until the sacrifice day. After the period of contamination, the 3 months groups were sacrificed, while the other groups stayed without treatment to complete their ages (6, 9 and 12 months). The animals femurs, tibia and vertebras (L5) were dissected to be analyzed on biometric, biomechanical and enzymatic parameters. To statistical analyze it was used the normality test Shapiro-Wilk, the variance tes Two-way analysis (ANOVA) (for time and treatment), and the Tukey Test to do multiple comparisons using Graphpad Instat (version 3.00 December 1997). All the values were expressed as media ± standard error media and the significance level was p ≤ 0.05. There was a tendency of a percent increase of mineral material, mineral and bone density and of the maximum force of femurs sample on contaminated groups related to their respective controls. The contaminated animals showed difference on the maximum force of the vertebras, which the 6 months had a higher value than the 3 months group. It was higher MMP-2 activity on mercury group than on the saline group with the same age. The results showed that the HgCl2 on 5m/Kg dose, when related to the control group, did not present difference of biometric, biophysical and biomechanical parameters on bone tissue of rats in development. The HgCl2 contamination stimulated the MMP-2 activity at the end of the contamination period and remained until 6 months after the contamination. / Devido à carência de dados sobre o envolvimento do mercúrio sobre alterações do metabolismo ósseo, torna-se importante investigar a influência do seu efeito sobre os parâmetros ósseos. Avaliou-se as possíveis alterações biométricas, físicas, biomecâncicas e enzimáticas (MMPs) ósseas em ratos intoxicados com cloreto mercuroso durante seu desenvolvimento. Os animais foram divididos em 4 grupos: 3m, 6m, 9m e 12 meses de vida. Os animais tratados com cloreto de mercúrio receberam HgCl2, e os controles, salina por gavagem gástrica. O tratamento iniciou-se aos 30 dias de vida do animal, 5 vezes por semana, durante 60 dias. A dose diária foi de 5mg/kg de massa corporal de HgCl2 e de 0,1ml de salina /100g de massa corporal. Os animais foram pesados 3 vezes por semana até o dia do sacrifício. Após esse período, o grupo 3m foi sacrificado por decapitação enquanto que os demais grupos permaneceram sem tratamento até que completassem a idade desejada (6m, 9m e 12 meses de vida). Os animais tiveram seus fêmures, tíbias e vértebras (L5) retirados para análise dos parâmetros biométricos, biomecânicos e enzimático. Para análise estatística dos resultados foi feito o Teste de normalidade Shapiro-Wilk, o teste de variança Two-way analysis (ANOVA) (para tempo e tratamento) e o Teste de Tukey para múltiplas comparações utilizando o programa Graphpad Instat (version 3.00 - dezembro de 1997). Todos os valores foram expressos como média ± erro padrão da media e o nível de significância adotado foi de p ≤ 0,05. Houve tendência de aumento de percentual do material mineral, densidade mineral e óssea e da força máxima suportada, das amostras dos fêmures dos grupos contaminados em relação aos seus controles respectivos. Os animais contaminados também apresentaram diferenças de força máxima das vértebras, onde o 6 meses foi maior em relação ao grupo 3M. Houve maior atividade das MMP-2 no grupo mercúrio em relação ao grupo salina de mesma idade. Os resultados desse trabalho mostraram que o HgCl2, na concentração de 5mg/kg PC, quando comparados com o grupo controle não apresentaram diferenças das alterações das propriedades biométricas, biofísicas e biomecânicas do tecido ósseo em desenvolvimento dos ratos. O tratamento com HgCl2 estimulou a atividade das MMP-2 nos animais no final do tratamento e permaneceu em um período de até 6 meses depois.

Title: Relationship between selected specific and general indicators of strength in water slalom competitors in category C1 Objectives: The aim of the study was to find out the relationship between the maximum strength tests at the gym and the explosive force test when paddling on flat water. Another aim of the thesis was to compare the measurement with results in selection races to Czech national team 2018. Methods: The test battery for general force tests included the bench press test, the attachment on the bench, the one arm attachment on the bench and the one arm pull up on the bar. To test the explosive force on a flat water we used a three-axis piezoelectric load cell 9137. Dewesoft Sirirus and Dewesoft, Dewetron, were used to diagnose the course of force. Correlation analysis was used to determine the relationship between the measurements. The degree of dependence was determined by the correlation coefficient value. Results: A strong dependence rate (r = ≥ 0.7) was demonstrated in the water test and the one arm attachment on the bench. There was no evidence of a strong degree of dependence on bench - press exercises (r = 0,63), the attachment on the bench (r = 0,58)and the one arm pull up on the bar (r = 0,04). The paddlers who achieved the best results in specific and general strength...

Seventeen strength and power athletes (n = 11 males, 6 females; height: 177.5 ± 7.0 cm, 165.8 ± 11.4 cm; body mass: 90.0 ± 14.1 kg, 66.4 ± 13.9 kg; age: 30.6 ± 10.4 years, 30.8 ± 8.7 years), who regularly performed weightlifting movements during their resistance training programs, were recruited to examine the effect of altering body posture and barbell position on the between-session reliability of force-time characteristics generated in the isometric mid-thigh pull (IMTP). After participants were familiarised with the testing protocol, they undertook two testing sessions which were separated by seven days. In each session, the participants performed three maximal IMTP trials in each of the four testing positions examined, with the order of testing randomized. In each position, no significant differences were found between sessions for all force-time characteristics (p = >0.05). Peak force (PF), time-specific force (F50, F90, F150, F200, F250) and IMP time-bands (0–50, 0–90, 0–150, 0–200, 0–250 ms) were reliable across each of the four testing positions (ICC ≥ 0.7, CV ≤ 15%). Time to peak force, peak RFD, RFD time-bands (0–50, 0–90, 0–150, 0–200, 0–250 ms) and peak IMP were unreliable regardless of the testing position used (ICC =15%). Overall, the use of body postures and barbell positions during the IMTP that do not correspond to the second pull of the clean have no adverse effect on the reliability of the force-time characteristics generated.

Die Ausprägung der Lateralität der Körperextremitäten steht in engem Zusammenhang mit der Hemisphärenspezialisierung des menschlichen Gehirns. Die Lateralität und die Dominanz einer Hemisphäre mit ihren Auswirkungen auf die Leistungsfähigkeit ist ein bislang unvollständig untersuchtes Phänomen im Sport. In der vorliegenden Arbeit soll daher die Bedeutung der Seitigkeitsausprägung im Rahmen sportlicher Bewegungsabläufe geprüft werden. Sowohl bei Messungen im "Freiwasser", als auch in der "Kanu–Gegenstromanlage" im Bereich des Kanurennsportes werden seit einigen Jahren sich in Qualität und Quantität unterscheidende Kraft–Zeit–Funktionen der linken und rechten Körperseite beobachtet, die zwar dokumentiert, aber bislang ungeprüft in ihrer Bedeutung als leistungsbeeinflussend angenommen werden.<br><br> Im Zeitraum von Oktober 1997 bis Oktober 2000 wurden 275 Kajakfahrer und Canadierfahrer im Alter zwischen 11 und 20 Jahren zweimal jährlich (März und Oktober) mit einem umfangreichen trainings- und bewegungswissenschaftlichen sowie biomechanischen Instrumentarium untersucht. Die Athleten gehören zum Nachwuchs- und Anschlusskader des LKV Brandenburg. Schwerpunkt der Fragestellung ist der Zusammenhang von auftretenden Kraftdifferenzen zwischen der linken und rechten oberen Extremität und sportartspezifischen Leistungen unter Laborbedingungen und Feldbedingungen. Es wurden objektive Daten zu ausgewählten Kraftfähigkeiten der oberen Arm–Beuge–Schlinge an einem Kraftdiagnosegerät, Kraftverläufe am Messpaddel während Leistungsüberprüfungen im "Kanu–Gegenstromkanal" und im "Freiwasser" über 250 m und 2.000 m im Jahresverlauf erhoben.<br><br> Die Ergebnisse zeigen einen Trend der im Altersverlauf ansteigenden Differenz der Mittelwertunterschiede in der Maximalkraft zwischen dem linken und rechten Arm. Bei bestehenden Maximalkraftdifferenzen zwischen linker und rechter oberer Extremität in der Längsschnittgruppe liegen die Leistungen mit dem rechten Arm deutlich über den Kraftleistungen des linken Arms und sind nicht zufällig. Mit steigendem Maximalkraftniveau nimmt überraschenderweise auch die Differenz der Maximalkraft zwischen der linken und rechten oberen Extremität trotz bilateralen Trainings zu. Die Ergebnisse der EMG–Analyse bestätigen, dass die Maximalkraft leistungsbestimmend für die Bootsleistungen ist. In den EMG–Signalverläufen werden die unterschiedlichen Belastungen der Labor– und Feldbedingungen mit individuellen Charakteristika nachgezeichnet. Deutlich unterscheiden sich die Kraftverläufe im "Freiwasser" gegenüber den Kraftverläufen in der "Kanu–Gegenstromanlage".<br><br> Bei der vorliegenden Untersuchung handelt es sich um eine erste empirische Arbeit zur Auswirkung von Seitigkeitsunterschieden in zyklischen Sportarten auf der Expertiseebene. In der Untersuchung wurden methodische Verfahren eingesetzt, die dem derzeitigen Forschungsstand in der Trainings- und Bewegungswissenschaft entsprechen. Neben varianzanalytischen Verfahren der Auswertung zur Darstellung von Mittelwertunterschieden und Zusammenhänge prüfenden Verfahren wurden ebenso explorative EMG–Analysen angewandt. Die Ergebnisse aus dem Längsschnitt belegen bei ausschließlich rechtshändigen Probanden, dass die Schlussfolgerung von bevorzugter Extremität auf ein höheres Kraftniveau nicht eineindeutig ist. Zwischen den oberen Extremitäten bei Kanurennsportlern bestehen nicht nur zufällige Kraftunterschiede, trotz des bilateralen Trainings. Kontrovers diskutiert wird die Beziehung von bevorzugter Extremität und der Höhe der Kraftentfaltung. Im Alltagsverständnis wird häufig angenommen, dass ein höheres Maximalkraftniveau in der Extremität vorliegen muss, die auch die bevorzugte (z.B. Schreibhand) ist (WIRTH & LIPHARDT, 1999). Diese Eindeutigkeit konnte in der durchgeführten Untersuchung nicht bestätigt werden. Wie die Ergebnisse dieser Untersuchung deutlich zeigen, nimmt mit der höheren Maximalkraft aber auch die Differenz der Kraftleistungen zwischen dem linken und rechten Arm bei bilateral ausgerichtetem Training zu. FISCHER (1988; 1992) wies nach, dass sich ein Training auf der subdominanten Seite in einem kontralateralen Leistungstransfer auf der dominanten Seite positiv auswirkte. Erkenntnisse von KUHN (1986) und HOLLMANN & HETTINGER (2000) unterstützen nachhaltig die Ergebnisse. Die EMG–Ergebnisse zeigen die individuelle Reaktion auf die Belastungsanforderungen. Die elektromyographischen Daten beziehen sich auf den neuromuskulären Komplex. Somit sprechen hohe Amplitudenwerte einerseits für eine hohe Innervation der beteiligten motorischen Einheiten an der Bewegungsausführung und andererseits für einsetzende Ermüdungserscheinungen im Muskel. In Bezug auf die Ermüdung der oberen Extremitätenmuskeln der rechten und linken Seite beschreiben WILLIAMS, SHARMA & BILODEAU (2002) keine signifikanten Unterschiede zwischen der dominanten und nichtdominanten Handseite. / The development of body extremity laterality is closely linked to hemisphere specialization of the human brain. Laterality, the dominance of one hemisphere, and the effect of these two phenomena on sports performance capacity have yet to be described in detail. The question arises as to whether performance differences between paired extremities and the attendant extent of this difference might determine performance levels. In flat water canoeing, measurements in flat water as well as in the canoe counter current system reveal force time functions of the left and right body side that differ in quality and quantity. These differences have been documented for a number of years. However, so far their influence on performance has been presumed to exist and no attempt has been made to explain them.<br><br> During the period from October 1997 to October 2000, 275 kayakers and canoeists between the ages of 11 and 20 were examined twice annually (March and October) using extensive training scientific, kinetic and biomechanical equipment. The athletes were members of a state-wide canoeing club.<br><br> The main focus of the study was the correlation between (a) force differences arising between the left and right upper extremity and (b) athletic performance under laboratory conditions and field conditions. The following data was gathered: selected strength capacities of the upper arm flexor at a static strength measurement system (Wick & Krüger, 1998), force curves at the measuring paddle during exercise tests using the canoe counter current system and canoeing times in flat water over 250 m and 2,000 m during the course of the year.<br><br> The results of the static maximum force test showed that the difference in maximum force between the left and right arm increases with age. In the cross-sectional group, maximum force differences were observed between the left and right upper extremity; in terms of strength performance the right arm was clearly superior to the left arm. Despite bilateral training, contrary to what might be expected, the difference in maximum force between the left and right upper extremity increases with rising maximum force level. The proportional relationship remains unaffected by this. The evaluation of force parameters from the longitudinal and cross-sectional standpoint does not provide any clear indication of performance dominance of a specific extremity. The differences of the force parameters between the left and right upper extremity as measured in the canoe counter current system and in flat water are not stable. An analysis of EMG results confirmed that the maximum force has a decisive effect on canoeing performance. Force curves in flat water differ markedly from force curves in the canoe counter current system.<br><br> The present investigation is a first empirical paper on the effect of laterality differences on expert athletes in cyclic sports. The methodologies applied during the investigation correspond to the present state of research in the fields of training science and human kinetics. Variance-analytical methods of evaluation for the representation of average value differences, procedures that search connections and explorative EMG analyses were used. Results from the longitudinal section indicate that with exclusively right-handed subjects the preferred extremity cannot biuniquely be shown to have a higher force level. This result is confirmed by the cross-sectional findings. Despite bilateral training, force differences are observed between the upper extremities of canoeists. However, there is ongoing controversy about the relationship between preferred extremity and the extent of force development. The preferred extremity (e.g. the writing hand) is commonly believed to possess the higher maximum force level (Wirth & Liphardt, 1999). Nonetheless, this assumption could not be confirmed during the present investigation. However, the results of this investigation clearly show that as maximum force increases, the difference in strength performance between the left and right arm increases, including when bilateral training is applied. Fischer (1988; 1992) showed that training the subdominant side positively affected the dominant side. This is attributable to contralateral achievement transfer. These results are strongly supported by the findings of Kuhn (1986) and Hollmann & Hettinger (2000). The proportional difference remains stable over time with the athletes studied. This too supports the concept that the preferred extremity benefits from positive transfer effects. The electromyographic data pertains to the neuromuscular complex. Thus high amplitude values suggest on one hand a high innervation of the motor units involved in the performance of the movement and on the other hand the first signs of muscle fatigue. Williams, Sharma & Bilodeau (2002) found no significant differences between fatigue levels in the upper extremity muscles of the dominant and non-dominant extremity.