369 research outputs found
The influence of pacing strategy on V̇O2 and supramaximal kayak performance
No full textD. BISHOP, D. BONETTI, and B. DAWSON. The influence of pacing strategy on [latin capital V with dot above]O2 and supramaximal kayak performance. Med. Sci. Sports Exerc., Vol. 34, No. 6, pp. 1041–1047, 2002.
Purpose: The purpose of this study was to investigate the effects of manipulating pacing strategy on [latin capital V with dot above]O2 and kayak ergometer performance in well-trained paddlers.
Methods: Eight well-trained kayak paddlers (500-m time = 115-125 s) first performed a graded exercise test for determination of [latin capital V with dot above]O2max and lactate (La-) parameters. On subsequent days and in a random, counterbalanced order, subjects performed a 2-min, kayak ergometer test using either an all-out start or even pacing strategy.
Results: There was a significantly greater peak power (747.6 ± 152.0 vs 558.3 ± 110.1 W) and average power (348.5 ± 47.6 vs 335.5 ± 44.8 W) using the all-out start strategy, when compared with the even-paced strategy. There was however, no significant difference between the two pacing strategies for peak [latin capital V with dot above]O2, accumulated oxygen deficit (AOD), peak [La-], or posttest pH. Using the all-out start, total [latin capital V with dot above]O2 was significantly greater (7.3 ± 0.8 vs 6.9 ± 0.8 L).
Conclusion: The results of this study indicate that 2-min kayak ergometer performance is significantly greater following an all-out start strategy when compared with an even-paced strategy. The improved performance appears to be attributable to faster [latin capital V with dot above]O2 kinetics, without a significant change in the total AOD (although the AOD distribution was altered)
The effect of three different warm-up intensities on kayak ergometer performance
No full textBISHOP, D., D. BONETTI, and B. DAWSON. The effect of three different warm-up intensities on kayak ergometer performance. Med. Sci. Sports Exerc., Vol. 33, No. 6, 2001, pp. 1026–1032.
Purpose: The purpose of this study was to investigate the influence of warm-up (WU) intensity on supramaximal kayak ergometer performance.
Methods: In the initial testing session, eight institute of sport kayak squad members performed a graded exercise test for determination of [latin capital V with dot above]O2max and lactate (La) parameters. In a random, counterbalanced order, subjects subsequently performed WU for 15-min at either their aerobic threshold (W1), their anaerobic threshold (W3), or mid-way between their aerobic threshold and anaerobic threshold (W2). A 5-min passive rest period and then a 2-min, all-out kayak ergometer test followed the WU.
Results: For the three different WU conditions, no significant differences were observed for average power, peak [latin capital V with dot above]O2, total [latin capital V with dot above]O2, total [latin capital V with dot above]CO2, or accumulated oxygen deficit (AOD) during the 2-min test. However, when compared with W3, differences in average power approached significance after both W1 (P = 0.09) and W2 (P = 0.10). Furthermore, when compared with W3, average power during the first half of the 2-min test was significantly greater after W2 (P W2>W3;P < 0.05) and blood [La] (W1<W2<W3;P < 0.05). Despite the significantly different metabolic acidemia after each WU condition, there were no significant differences in the [latin capital V with dot above]O2 responses to the 2-min test. However, the greater metabolic acidemia after W3 was associated with impaired 2-min kayak ergometer performance.
Conclusions: It was concluded, that although a degree of metabolic acidemia may be necessary to speed O2 kinetics, if the WU is too intense, the associated metabolic acidemia may impair supramaximal performance by reducing the anaerobic energy contribution and/or interfering with muscle contractile processes
Dr Darrell Lewis
No full textNorthern Territory author and anthropologist, Dr Darrell LewisDonated by David Ritchie, 22/06/2016Photographs of the Kenbi Handover 2016, the resolution of the 37 year Kenbi Land Claim over the Cox Peninsula. The handback, presided over by Prime Minister Malcolm Turnbull, took place at Mandorah on 21 June 2016 and was attended by many of the people who had worked on, or been involved in the landclaim processes
Darrell Huff and Fifty Years of How to Lie with Statistics
No full textOver the last fifty years, How to Lie with Statistics has sold more copies than any other statistical text. This note explores the factors that contributed to its success and provides biographical sketches of its creators: author Darrell Huff and illustrator Irving Geis
The effect of an intermittent, high-intensity warm-up on supramaximal kayak ergometer performance
No full textIt has previously been shown that the metabolic acidaemia induced by a continuous warm-up at the 'lactate threshold' is associated with a reduced accumulated oxygen deficit and decreased supramaximal performance. The aim of this study was to determine if an intermittent, high-intensity warm-up could increase oxygen uptake (VO2) without reducing the accumulated oxygen deficit, and thus improve supramaximal performance. Seven male 500 m kayak paddlers, who had represented their state, volunteered for this study. Each performed a graded exercise test to determine VO2max and threshold parameters. On subsequent days and in a random, counterbalanced order, the participants then performed a continuous or intermittent, high-intensity warm-up followed by a 2 min, all-out kayak ergometer test. The continuous warm-up consisted of 15 min of exercise at approximately 65\% VO2max. The intermittent, high-intensity warm-up was similar, except that the last 5 min was replaced with five 10 s sprints at 200\% VO2max, separated by 50 s of recovery at approximately 55\% VO2max. Significantly greater (P < 0.05) peak power (intermittent vs continuous: 629 +/- 199 vs 601 +/- 204 W) and average power (intermittent vs continuous: 328 +/- 39.0 vs 321 +/- 42.4 W) were recorded after the intermittent warm-up. There was no significant difference between conditions for peak VO2, total VO2 or the accumulated oxygen deficit. The results of this study indicate that 2 min all-out kayak ergometer performance is significantly better after an intermittent rather than a continuous warm-up
Coos River Basin fish management plan
No full textprepared by Linda J. Wagoner, Kim K. Jones, Reese E. Bender, Jerry A. Butler, Darrell E. Demory, Thomas F. Gaumer, Joel A. Hurtado, William G. Mullarkey, Paul E. Reimers, Neil T. Richmond, Thomas J. Rumreich.This archived document is maintained by the State Library of Oregon as part of the Oregon Documents Depository Program. It is for informational purposes and may not be suitable for legal purposes.Includes bibliographical references (pages 122-124).Mode of access: Internet from the Oregon Government Publications Collection.Text in English
Effect of Brief-Intermittent Hypoxic Exposure on High-Intensity Kayaking and Cycling Performance
No full textAdaptation to the shortage of oxygen at altitude (hypoxia) promotes physiological changes which could enhance endurance performance. Consequently, altitude training has become a popular practice among competitive endurance athletes. Since its inception, the live-high train-low paradigm (LHTL) has been widely regarded as the most effective approach to altitude training. Over the past decade, brief intermittent simulation of LHTL via the use of hypoxic inhalers and re-breathing devices has gained increased popularity, but the evidence supporting their use is limited and conflicting. The experimental studies in this thesis investigated the response of sea level exercise performance and related physiological measures following adaptation to the usual and a novel protocol of brief intermittent hypoxia. I intended to perform all experimental studies on flat-water kayakers. Therefore, an initial requirement of this thesis was to establish the smallest worthwhile effect in performance for this sport. The final study utilising a meta-analytic approach was conducted to compare the effectiveness of brief intermittent hypoxia to other natural and simulated protocols, and to investigate the topical issue of what physiological responses mediate performance changes following hypoxic exposure. In Study 1, the typical variation in competitive performance of elite flat-water canoeists was investigated using a repeated-measures analysis of race times. For individual flat-water canoeing events, the smallest worthwhile change in performance time was ~0.5%. In two separate experimental studies, adaptation to 60 min per day of brief intermittent hypoxia consisting of alternating 5 min intervals of hypoxia and normoxia for 3 weeks (5 days per week) using a nitrogen filtration device resulted in clear enhancement of endurance performance (~5%) for kayakers (Study 2) and cyclists (Study 3). Clear enhancements in repeat sprint performance were observed for kayaking only. The physiological mechanisms underlying performance changes were unclear. Modification of the hypoxic and normoxic intervals (Study 3) did not result in any clear alterations in performance or physiological mechanisms. The meta-analysis (Study 4) revealed clear enhancements in endurance power output of 1-3% in sub-elites following adaptation to hypoxia with the natural altitude protocols, and with two of the artificial-altitude protocols (LHTL-long and LHTL-brief-intermittent). In elite athletes the enhancements tended to be smaller and were clear only for the natural protocols. These enhancements could be mediated by VO2max, although other mechanisms may be possible
Effect of brief-intermittent hypoxic exposure on high-intensity kayaking and cycling performance
No full textAdaptation to the shortage of oxygen at altitude (hypoxia) promotes physiological changes which could enhance endurance performance. Consequently, altitude training has become a popular practice among competitive endurance athletes. Since its inception, the live-high train-low paradigm (LHTL) has been widely regarded as the most effective approach to altitude training. Over the past decade, brief intermittent simulation of LHTL via the use of hypoxic inhalers and re-breathing devices has gained increased popularity, but the evidence supporting their use is limited and conflicting. The experimental studies in this thesis investigated the response of sea level exercise performance and related physiological measures following adaptation to the usual and a novel protocol of brief intermittent hypoxia. I intended to perform all experimental studies on flat-water kayakers. Therefore, an initial requirement of this thesis was to establish the smallest worthwhile effect in performance for this sport. The final study utilising a meta-analytic approach was conducted to compare the effectiveness of brief intermittent hypoxia to other natural and simulated protocols, and to investigate the topical issue of what physiological responses mediate performance changes following hypoxic exposure. In Study 1, the typical variation in competitive performance of elite flat-water canoeists was investigated using a repeated-measures analysis of race times. For individual flat-water canoeing events, the smallest worthwhile change in performance time was ~0.5%. In two separate experimental studies, adaptation to 60 min per day of brief intermittent hypoxia consisting of alternating 5 min intervals of hypoxia and normoxia for 3 weeks (5 days per week) using a nitrogen filtration device resulted in clear enhancement of endurance performance (~5%) for kayakers (Study 2) and cyclists (Study 3). Clear enhancements in repeat sprint performance were observed for kayaking only. The physiological mechanisms underlying performance changes were unclear. Modification of the hypoxic and normoxic intervals (Study 3) did not result in any clear alterations in performance or physiological mechanisms. The meta-analysis (Study 4) revealed clear enhancements in endurance power output of 1-3% in sub-elites following adaptation to hypoxia with the natural altitude protocols, and with two of the artificial-altitude protocols (LHTL-long and LHTL-brief-intermittent). In elite athletes the enhancements tended to be smaller and were clear only for the natural protocols. These enhancements could be mediated by VO2max, although other mechanisms may be possible
\u3ci\u3eThe Adventures of Darrell and the Invincible Man\u3c/i\u3e
No full textThe Adventures of Darrell and the Invincible Man has been nominated for the prestigious National Association of Multicultural Education Outstanding Multicultural Children\u27s Book Award.
Research literature is replete with studies that demonstrate how and why Black children when asked to draw themselves do so almost exclusively by depicting themselves as White. Researchers have concluded that this predilection is the result of the Black child being acculturated in a White racist society. This book explores identity development in minority, particularly Black, youth. This book provides a riveting deconstruction of how minority children adopt the White, western ideal as their self-image and the proper way to make the children themselves aware of their subconscious adoption and how the astute multicultural educator, parents, and anyone interested in identity development in minority, particularly, black youth, can redirect this propensity.
Dr. Omowale Akintunde has published a plethora of research regarding multicultural education, black identity development, white privilege, and how these dynamics impact and influence early childhood education. He is also the author of Multiculturalism and the Teacher Education Experience: Essays on Race, Class, and Culture (iUniverse, 2007). He has served on the Editorial Board of the Official Journal of the National Association of Multicultural Education and is currently serving on the national executive board of the National Association of Multicultural Education (NAME) and the National Board of Peace Education (NAPE). The Adventures of Darrell and the Invincible Man is certain to become a necessary and celebrated addition to the field of multicultural children\u27s literature.https://digitalcommons.unomaha.edu/facultybooks/1045/thumbnail.jp
Reflection Roundtable: White Supremacy in Oregon History
No full textOregon Historical Society Panel Discussion with Dr. Karen Gibson, Dr. Darrell Millner, Dr. Carmen Thompson, and Justice Adrienne Nelson, Moderator. Reflection on Hatfield Lecture by Henry Louis Gates, Jr. October 29, 2020. This panel reflects upon the Oregon Historical Society event two days prior, the second virtual Hatfield Lecture Series talk held October 27 that featured the one and only Henry Louis Gates, Jr., host of Finding Your Roots and author of a number of books including his latest work, Stony the Road: Reconstruction, White Supremacy, and the Rise of Jim Crow
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