In an effort to apply Cumulative Risk Assessment (CRA) as developed by the U.S. EPA, the present study investigates the cumulative risks to Eastern oysters due to multiple stressors such as salinity, temperature and oxygen and carbon dioxide. I also compared the effectiveness of the Hazard Quotient Method (HQ) in CRA. Ambient conditions in the James River, VA were obtained from the Virginia DEQ database and respiratory responses were estimated using values from the literature. The multiple environmental stresses are evaluated using a probabilistic analysis that combines the environmental conditions. It was concluded that salinity was the most influential stressor in the model. Other risks were identified contributing to the vulnerability of the oysters. Crystal Ball simulations yielded that the oxygen uptake of oysters reduced by more than 29%. The HQ method was found to be inappropriate in analyzing cumulative risks for CRA. Oyster populations are dramatically declining in the James River and the Chesapeake Bay. Hence, effective oyster restoration activities are underway to rebuild oyster populations in the James River and throughout the Bay area.

The purpose of this study was to describe mathematically the oxygen uptake kinetics during cycle ergometry, and to examine the effect of intensity on the kinetic responses within the severe domain. Sixteen volunteers performed a series of exercise tests at a range of intensities selected to elicit fatigue in ~3 to 10 min. A simple mono-exponential model effectively described the response across all intensities. There was a positive correlation between the response time and the time to fatigue, demonstrating that the maximal oxygen uptake was achieved faster at higher intensities within the severe domain. Models incorporating two components effectively described the responses only in tests lasting 8 min or more. It was concluded that there is a second, slow component in the oxygen uptake response only at the lower intensities within the severe domain.

Title of master thesis Determination of climbing specific maximal oxygen uptake during climbing with increasing inclination and constant speed. Work objectives To review the determination of climbing specific maximal oxygen uptake during climbing with increasing inclination and constant speed. Methods Twenty six climbers with climbing ability on UIAA scale from 4th to 10th degree were participated in this study. Maximal specific oxygen uptake was measured by climbing test, to exhaustion on climbing wall, where the inclination were changed from 95ř (105ř) to 135ř every three minutes. Speed of climbing was constant on 25 movements·min-1 . After a rest, the participants went a maximal running test on treadmill. There were evaluated relationships between climbing ability, inclination and cardiopulmonary variables. Results In maximal climbing test, climbers achived plato on value 40 ± 3,5 ml·kg-1 ·min-1 , without influence on climbing ability or inclination. The climbing ability most corelated with achived inclination r = 0,89 and heart rate r = 0,41. Our study confirmed disproportional rising of heart rate against oxygen uptake. Furthermore, there was a strong relationship to be found between ventilation per 1l oxygen to RER indicating specific breathing mechanism of advanced climbers. More demanding...

O consumo máximo de oxigênio (VO2máx), o limiar ventilatório (LV), ponto de compensação respiratória (PCR) e a economia de corrida (EC) são importantes variáveis fisiológicas associadas com a aptidão aeróbia em corrida. Acredita-se que o polimorfismo da enzima conversora de angiotensina (ECA) possa estar influenciando nos valores dessas variáveis. Contudo, essa relação causal não tem sido amplamente estudada durante a corrida. Dessa forma, o objetivo do presente trabalho foi investigar a associação entre os genótipos da ECA e o VO2máx, LV, PCR e EC mensuradas durante a corrida em esteira. Cento e cinquenta (n = 150) voluntários fisicamente ativos realizaram os seguintes testes: a) teste incremental máximo para determinação do VO2máx, LV e PCR; b) dois testes de velocidade constante (10 km/h e 12 km/h) em esteira para determinação da EC. Os genótipos apresentaram a frequência de: II = 21% ; ID = 52% e DD = 27%. Os resultados apresentaram uma tendência dos indivíduos com o genótipo II apresentarem maiores valores do VO2máx (p = 0.08), bem como a análise do efeito prático apresentou um possível efeito benéfico desse genótipo. No entanto, não foi constatada diferença entre os valores do LV, PCR, e EC entre os indivíduos. Esses resultados sugerem que o genótipo II da ECA pode estar influenciando nos valores da variável máxima relacionada com o consumo de oxigênio / The maximal oxygen uptake (VO2máx), ventilatory threshold (VT), respiratory compensation point (RCP), and running economy (RE) are important variables associated with running aerobic fitness. However, the influence of Angiotensin Converting Enzyme (ACE) polymorphism on these variables determined in running has not been largely investigated. Therefore, the present study aimed to investigate the relationship between ACE genotypes and maximal oxygen uptake, respiratory compensation point, and running economy measured in running. One hundred and fifty (n = 150) physically active young men performed the following tests: a) a maximal incremental treadmill test to determine VO2máx and RCP, b) two constant-speed running test (10 km.h-1 and 12 km.h-1) to determine the RE. The genotype frequency were II = 21 %; ID = 52 %; DD = 27 %. There were a likely beneficial effect and a tendency for the participants with ACE II genotype to have higher VO2max values than DD or ID genotypes (p = 0.08) and the smallest worthwhile effects show a beneficial effect. There were not associations between the genotypes for RCP and RE. These findings suggest that II ACE genotype would influence in maximal variable correlated with oxygen consumption

The purpose of this study was to predict VO2pak using ratings of perceived exertion (RPE), heart rate (HR), and percent fat (PFAT). Subjects were males (n= 60) (PFAT, M SD = 14.4 6.1) and females (n= 67) (PFAT, M SD = 23.4 4.9) with ages ranging from 18 to 33 years. Subjects performed an incremental cycle ergometer protocol and RPE, HR and Vo2 were measured at each stage until VO2 ak was achieved. Mean RPE and HR at the submaximal workload of 100 watts were, (RPE100) M= 12.7 2.6 and (HR100) M= 146.924.7 respectively. Correlations (p< .001) with VO2p. were -.75 (PFAT), -.66 (HR100), -.67 (FIPE100). The multiple correlation using PFAT, HR100, and RPE100 as predictors of VO2pak was .83 (SEE= 5.28 ml-kg BW'smin"). Each predictor contributed to the correlation (p<.01). The results indicate that PFAT combined with exercise responses of RPE and HR provide valid estimates of VO2peak with a relatively small SEE.

O triatlo é um esporte composto por natação, ciclismo e corrida. Embora existam evidências que apontem influência do ciclismo prévio à corrida, mecanismos que expliquem fatores bioenergéticos e biomecânicos na corrida após o ciclismo não são completamente compreendidos. O objetivo deste estudo foi investigar os efeitos do ciclismo prévio, sobre a corrida, em triatletas de nível médio nos seguintes parâmetros: economia de corrida (ECO), eficiência mecânica (Eff), trabalho mecânico (Wmec), rigidez do membro inferior e do sistema massa-mola (Kleg e Kvert) e comprimento e frequência de passada (CP e FP). Participaram do estudo 14 triatletas de nível médio (média ± DP; VO2max = 65,3 ± 2,7 ml.kg-1.min-1, idade = 30 ± 5 anos; tempo de prática = 6,8 ± 3,0 anos). Os atletas realizaram quatros testes: 1) um teste máximo de corrida, 2) um teste máximo de ciclismo, randomizados, 3) um teste de ECO de 20 minutos a 14km.h-1 com coleta cinemática e do consumo de O2 em quatro momentos, e 4) o mesmo teste após pedalar durante 30 minutos na potência equivalente a 80% do 2° limiar ventilatório (2ºLMV), realizados de forma randomizada. A ECO não presentou diferença quando realizada após o ciclismo em relação a corrida sem corrida isolada, assim como o Wmec que foi menor ao final do teste de corrida isolada (p<0,05). A Eff no teste com ciclismo prévio no último momento foi maior que a corrida isolada (0,60 x 0,52) e o contrário ocorreu com Kleg (20,2 x 24,4 kN.m-1) e Kvert (7,1 x 8,2k N.m-1, p<0,05). FP foi maior e CP menor em todos os momentos da corrida com ciclismo prévio p<0,05. A ECO, Wmec, Kleg e Kvert são mantidos ao longo do teste de velocidade constante quando realizado ciclismo em intensidade moderada, demonstrando que o ciclismo prévio à corrida pode contribuir para a manutenção da Eff em triatletas, porém ajustes ocorrem no CP e FP para manutenção da ECO. / The triathlon is composed of swimming, cycling and running. Although there are evidences indicating the influence of cycling prior to running, bioenergetics and biomechanics mechanisms describing the effects on running are not completely understood. The aim of this study was to investigate the effects of cycling on running economy (RE), mechanical efficiency (Eff), mechanical work (Wmec), spring stiffness (Kleg e Kvert) stride frequency and length (SF and SL). Fourteen intermediate level triathletes (mean ± SD: maximum oxygen uptake, VO2max = 65.3 ± 2.7ml.kg-1.min-1, age = 30 ± 5 years, practice time = 6.8 ± 3.0 years) performed four tests: 1) running maximal oxygen uptake test and 2) cycling maximal oxygen uptake test (VO2max) randomized and 3) running economy test of 20 minutes at 14 km.h-1 with kinematic and oxygen consumption data collected in four moments and 4) the same test after 30 minutes on the power equivalent to 80% of 2º ventilatory threshold (VT2) randomized. No differences were observed post cycling in ECO or Wmec that was lower at the end of isolated running (p<0.05). The Eff in running test post cycling at the last moment was greater than the isolated run (0.60 x 0.52) and opposite was observed with Kleg (20.2 x 24.4 kN.m-1) and Kvert (7.1 x 8.2 kN.m-1, p<0.05). SF was higher and SL smaller all the moments in the running post cycling p<0.05). The RE, Wmec, Kleg e Kvert are maintained throughout the constant speed test when performed at moderate intensity cycling. Therefore, we concluded that prior cycling race contributes to the maintenance of Eff in triathletes, and adjusts occur in CP and FP for maintenance of ECO.

O objetivo deste estudo foi descrever e analisar respostas agudas a diferentes frequências gestuais controladas do nado crawl em parâmetros biomecânicos, coordenativos e fisiológicos em intensidade relativa à velocidade de 95% da velocidade média de um teste de 400 m nado crawl, até a exaustão. Foram voluntários 12 nadadores do sexo masculino (idade: 23,6 ± 6,0 anos; estatura: 178,2 ± 4,5 cm; envergadura: 185,2 ± 4,9 cm; massa corporal total: 74,4 ± 8,9 kg) que treinavam, pelo menos, 12 horas por semana (melhor desempenho em 400 m nado crawl: 275,5 ± 16,2 s). Foram realizados: i) familiarização ao esnorquel, metrônomo, pacer e escala de 15 pontos de Borg; ii) determinação da velocidade média (V400) em teste máximo de 400 m (T400); iii) séries de nado contínuo a 95% da V400 em (a) Frequência gestual (FG) livre, (b) FG aumentada (110% da FG média da série de FG livre) e (c) FG reduzida (90% da FG média da série de FG livre). Foram avaliados: (i) parâmetros biomecânicos (frequência média de ciclos de braçadas - FG, distância média percorrida pelo corpo a cada ciclo de braçadas - DC, velocidade média de nado - VN; variação tridimensional intracíclica da velocidade do centro – VIV, VIVx, VIVy, VIVz, índice de coordenação - IdC, duração das fases de braçada – entrada + apoio, puxada, empurrada e recuperação; duração das fases propulsivas e não-propulsivas - FP e FNP; tempo propulsivo - Tprop) e eficiência de Froude ; e (ii) parâmetros fisiológicos (consumo de oxigênio – V̇O2, concentração sanguínea de lactato – [La], esforço percebido – EP), frequência cardíaca (FC) e amplitude (Ap), tempo de atraso (τd) e constante temporal (τ) (cinética do consumo de oxigênio) Dados foram obtidos antes, durante (momentos inicial, intermediário, final e pico) das séries de nado contínuo. Parâmetros biomecânicos de nado foram obtidos por cinemetria 3D. O V̇O2 foi mensurado respiração por respiração utilizando o ergoespirômetro K5 e esnorquel Aquatrainer (ambos Cosmed). Tempo total até a exautão, de cada série, foi também registrado. Foram utilizadas estatística descritiva e inferencial. Os princiapais achados indicaram que: i) entre as condições de FG, nadadores incrementam a VIV e a  com a FG controlada. Ao nadar com a FG aumentada, o IdC, a duração das fases de puxada e de empurrada e a FP aumentam e a constante temporal (τ) diminui. Já, ao nadar com a FG reduzida os valores do IdC, da duração da fase de recuperação e da FNP diminuem. Aumento ou redução da FG não alteram as respostas das demais variáveis fisiológicas e do tempo total até a exaustão (TTE). ii) Entre os momentos da FG livre, os nadadores aumentaram os valores da FG, da [La], do EP, da FC e do V̇O2 e diminuíram os valores da DC, da  e da VIVz. iii) Entre os momentos da FG aumentada, os nadadores diminuíram a VIV e a VIVx e aumentaram o Tprop, a [La], o EP, a FC e o V̇O2. iv Entre os momentos da FG reduzida, os nadadores diminuíram os valores do IdC, da VIV, da VIVx e da VIVz ao passo que aumentaram a , a [La], o EP, a FC e o V̇O2. Reduzir a FG, para a mesma velocidade, induz à diminuição da duração das fases não-propulsivas e à aumento da eficiência de Froude, enquanto as fases de puxada e de empurrada aumentam. A condição de FG aumentada diminuiu a constante temporal da cinética do consumo de oxigênio quando comparada às FG livre e reduzida. O controle da FG (com aumento de 10% e redução de 10%) durante o nado com velocidade controlada a 95% da V400 altera a magnitude dos parâmetros de braçada em ambas as situações. Enquanto a FG e a velocidade forem mantidas, as propriedades temporais do ciclo de braçada alteram características importantes para o desenvolvimento da técnica, da energética e consequentemente a melhora do desempenho dos nadadores. / The objective of this study was to describe and to analyze biomechanical, coordinative and physiological parameters acute responses to different control crawl frequencies in until exhaustion in intensity relative to the 95% speed of a 400 m front crawl test. Volunteered to this study 12 male swimmers (age: 23.6 ± 6.0 years; height: 178.2 ± 4.5 cm; upper arm span: 185.2 ± 4.9 cm; total body mass: 74.4 ± 8,9 kg) training at least 12 hours per week (best performance in 400 m front crawl: 275.5 ± 16.2 s). The procedures were: i) familiarization to the Borg's 15-point scale, snorkel, metronome and pacer; ii) determination of the mean velocity (V400) in a 400 m maximum front crawl test (T400); and iii) series in continuous swimming at 95% of the V400 at (a) free stroke frequency (FG); (b) increased FG (110% of the mean FG of the free FG series) and (c) reduced FG (90% of the mean FG of the free FG series. Biomechanical (mean stroke rate – FG, stroke length, swimming speed, swimming velocity tridimensional intracyclic variation - VIV, coordination index - IdC, duration of stroke phases - entry, pull, push and recovery, duration of propulsive and non-propulsive phases - FP and FNP, propulsive time - Tprop and Froude efficiency - ) as well as physiological parameters (oxygen consumption - V̇O2, lactate blood concentration - [La], perceived exertion - PE, heart rate (HR) and, regarding the oxygen uptake kinetics: amplitude - Ap, time delay (τd) and time constant - τ were obtained and assessed. Each series total time to exhaustion (TTE) was even registered. Data were obtained before, during (initial, intermediate, final and peak moments) of the continuous swimming series. Biomechanical swimming parameters were obtained by 3D cinemetry. The V̇O2 was measured breath-by-breath using the K5 ergometer and the Aquatrainer snorkel (both Cosmed). Descriptive and inferential statistics were used. The main findings indicated that: i) between the FG conditions, swimmers increase VIV and  with controlled FG. When swimming in increased FG, the IdC, the duration of the pull and push phases and the FP increase and the τ decreases. Already, when swimming in FG reduced the IdC, the duration of the recovery phase and the PNF decreased. Increasing or reducing FG does not alter the responses of the other physiological variables and the TTE. ii) Among the moments of free FG, swimmers increased the values of FG, [La], PE, HR and V̇O2 and decreased the values of DC,  and VIVz. iii) Among the moments of increased FG, swimmers decreased VIV and VIVx and increased Tprop, [La], PE, HR and V̇O2. iv) Among the moments of the reduced FG, swimmers decreased the values of IdC, VIV, VIVx and VIVz while increasing [La], EP, HR and V̇O2. Reducing FG at the same speed induces a decrease in the duration of non-propellant phases and an increase in Froude efficiency, while the pull and push phases increase. The increased FG condition decreased the τ when compared to free and reduced FG. The control of FG (10% increase and 10% reduction) during swimming at 95% V400 alters the magnitude of the stroke parameters in both situations. While FG and velocity are maintained, the temporal properties of the stroke cycle alter important characteristics for the development of the technique, energy and consequently the improvement of swimmers' performance.

Made available in DSpace on 2014-06-11T19:30:53Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-08-11Bitstream added on 2014-06-13T20:40:45Z : No. of bitstreams: 1 caputo_f_dr_rcla.pdf: 655245 bytes, checksum: 03656379a3c3b9ba9616d1e9353a4f3d (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Os principais objetivos deste estudo foram: 1) Determinar e comparar em cicloergômetro a cinética do consumo de oxigênio (V02) em intensidades do domínio severo (constante de tempo - Tais), e a maior intensidade (Isup) e o menor tempo de exercício (Tsup) onde o VO2max pode ser alcançado, em ciclistas (dc), corredores (COR) e indivíduos sem treinamento (ST); 2) Verificar a validade de um modelo para estimar indiretamente a 1sup (lsup') e Tp (Tsup'). Onze COR, quinze dc e dez ST realizaram em dias diferentes os seguintes testes: 1) teste incremental para determinação do VO2max e da intensidade correspondente ao VO2max (lVO2max); 2) Testes de cargas constantes realizados aieatoriamente a 95. 100 e 1 1O%lVO2max, para determinar o tempo de exaustão (Tlim), Tau lsup' e Tsup'; 3) 2 a 4 testes de carga constante onde a intensidade foi aumentada ou diminuída até que o VO2max não pudesse ser atingido para determinação da lp e TSU. O tempo para atingir o VO2max (TAVO2max) foi calculado através de um modelo de uste mono-exponencial assumindo um valor de 4,6 vezes o Tau. O Tsup' foi estimado individualmente através da regressão linear entre os TAVO2max e seus respectivos Tlim. A l' foi estimada através do modelo hiperbólico de potência critica A ISUP foi considerada como a maior intensidade onde a média do V02 de três valores consecutivos de 5 s foi maior ou igual à média do VO2max obtidos nos testes incrementa] e de carga constante menos um desvio padrão. O Tsup foi considerado como o Tlim associado à ISLP. Os valores de VO2max (mlkg'-miW') (ST = 42,2 l 4,0; COR 54,6 l 5,5; CIC = 64,5 l 6,4) foram significativamente diferentes entre os grupos. O TSUP e o Tau (todas as intensidades) foram semelhantes entre COR e ST e ambos maiores em relação ao CIC. / The main objectives of the present study were: 1) To determine and to compare in cycle ergometer the oxygen uptake (V02) kinetics in the severe intensity domam (time constam - Tau), and the highest intensity (Isup) and the shortest exercise time (Tsup) which VO2max can be elicitcd in cyclists (dc), runners (COR) and untrained subjects (ST); 2) to evaluate the validity of a model for estimating the 1sup (lsup) and Tsup (Tsup'). Fifleen CJC, eleven COR and ten ST performed in different days the following tests: 1) incrementa! tests for determination of VO2max and lhe intensity corresponding at VO2max (IVO2max); 2) fatigiing constam power tests at 95, 100 e 110% !VO2max lo determine the time to exhausúon (TIim), Tau, 1sup' and Tsp'. 3) 2 to 4 fatiguing constant power tests to determine 1sup e lhe power output was decreased or increased uniu VO2max can not be elicited. The time lo achieve VO2max (TAVO2max) was calculated by a monoexponentia! fit where was assumed a fixed value of 4,6 limes Tau. Linear regression techniques were used to describe the relalionship between lhe TAVO2max and Thm lo estimate indirectly Tsup'. lsup' was calcu!ated using the critical power model. Ip was assumed to be the highest intensity where lhe 5 s V02 values determined from rolling averages of 5 s samples was equai or higber than the average of VO2max obtained in lhe incrementa] and constam power tesls minus one standard deviation. Tsup was lhe TIjm associated with lsup. VO2max values (rnlKg1min') (ST = 422 l 40; COR 54.6 l 5.5; CIC = 64.5 l 64) were significanl!y differenl among lhe grcups. No significanl differences were found in Tp and Tau (ali exercises intensities) between COR and ST, however both groups showed higher values compared to dc in.

The purpose of this study was to assess the performance, ratings of perceived exertion, metabolic responses, and energy expenditure as individuals participated in interactive video game play. There were 14 participants that participated in the study, whose age was 20.1 ± 1.64 years of age. Participants completed a maximal aerobic test to exhaustion (VO2max test), and then 30 minute testing session on both the Kinect Adventures (K) and Wii Fit Plus game. Data were analyzed using a dependent t-test and one-way ANOVA. Significance was accepted at P ≤ 0.05. Energy expenditure and RPE were significant in both exergames interactive game play P=0.044 and P < 0.05, respectively. In addition, heart rate (P=0.001) and performance during exergame play P=0.00015 were of significance in the Xbox Kinect and Wii Fit Plus. In conclusion, we found that individuals participating on the exergame Xbox Kinect expends more calories and work at a higher intensity than the Wii Fit Plus, thus justifying an alternative way to participate in physical activity via exergames. As an alternative way to exercise, individuals can meet the daily requirements of energy expenditure of moderate intensity, which is 150-400 kcals.

The purpose of this study was to determine the validity of the Ebbeling one-stage submaximal treadmill protocol to estimate maximal oxygen uptake in overweight males and females. Forty-five male and females (36.5±10.9 years; 170.2±9.9 cm; 77.9±9.0 kg) were categorized into overweight groups using a BMI of 25-29.9 kg/m2. The subjects performed a submaximal protocol that consisted of one 4-minute stage with individualized speeds of 2.0-4.5 mph at 5% grade and subsequently performed a maximal exercise test. There were significant relationships between observed and estimated VO2max for males (r=.796), females (r=.426), and gender combined (r=.844). There was an underestimation in the estimation of VO2max in the present study when comparing males (10%), females (26%) and gender combined (17%) subjects. The results indicated that a body mass index between the values of 25-29.9 kg/m2 did create a difference in estimating VO2max in the present study when comparing that to Ebbeling et al. (1991).Ball State UniversityMuncie, IN 47306 / School of Physical Education