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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Effect of brief-intermittent hypoxic exposure on high-intensity kayaking and cycling performance a thesis submitted to AUT University in fulfilment of the degree of Doctor of Philosophy, February 2008 /

Bonetti, Darrell, L. January 2008 (has links)
Thesis (PhD) -- AUT, 2008. / Includes bibliographical references. Also held in print (156 leaves ; 30 cm.) in City Campus Theses Collection (T 613.711 BON)
2

Naturturism i Höga kusten : Förutsättningar för naturturism i form av kajakpaddling i Höga kusten

Libell, Joel January 2014 (has links)
Nature tourism in the High Coast of Sweden The conditions for nature tourism in the form of kayaking in the High Coast of Sweden. The aim of this study was to investigate the conditions for nature tourism in the form of kayaking in the High Coast of Sweden. The work focused on examining: the impact of protected areas, logistics and security for the kayak activity, visible evidences from the last glacial period (Weichsel), isostatic uplift and coastal processes, and also time- and site specific environmental effects of kayaking. Three destinations were selected as the main investigation sites.   In a protected area there are regulations that limits activities that may be carried out. Protected areas also promote outdoor recreation as a main goal. Logistics and security risks were documented for possible starting locations and routes. The results showed that evidences of glacial processes, isostatic uplift and coastal processes were visible at all three destinations. Trysunda showed the greatest presence of traces/kilometer. However, Trysunda was surveyed by hiking which may have affected the results. Trysunda showed the largest number of evidences of coastal processes, which may depend on the high exposure of this island to wave energy. At all three destinations environmental effects were found as abrasion on the vegetation as well as the disturbance of birds.   The conclusion is that all three destinations represent good sites for the experience of distinct educational traces of glacial and postglacial processes. Furthermore, the study emphasizes that the kayaker should have some experience of previous kayaking. The kayaker can benefit from the free facilities established in the protected areas.
3

An investigation to identify changes in power of the kayaking stroke following manipulation of the cervical spine in asymptomatic kayakers

Cuninghame, Neil Mark January 2009 (has links)
Dissertation in partial compliance with the requirements for a Master's Degree in Technology: Chiropractic, submitted to the Faculty of Health at the Durban University of Technology, 2009. / Although kayaking is an Olympic sport and said to be one of the top ten growth sports in America, relatively little literature has been written on it by sports scientists and there is a paucity of available literature. Previous research has described the effects of spinal manipulation on muscles at distant sites to the joint being manipulated, and there have been trends which have shown a positive increase in strength and in muscle activity at these sites. There has, however, been a lack of literature to show that these positive trends would influence sporting performance in any way. 30 volunteer kayakers, who train and compete on a regular basis, were actively recruited and randomly allocated into one of three groups. Group 1 received manipulation on a fixated cervical segment, group 2 on a non-fixated cervical spine segment, and group 3 received placebo laser to the posterior cervical area. Subjects were then required to complete two 200m sprint tests on a kayak ergometer. Measurements were taken pre and post manipulation and included maximum watts recorded for the duration of the sprint test and time taken to complete 200m. Although no statistically significant results were found between the groups, trends revealed that in group 1, which received spinal manipulation on a fixated joint, there was an increase in the mean peak watts post manipulation, as compared to the placebo and non-fixated groups which showed a decrease in peak watts post manipulation. Group 1 also demonstrated a mean decrease in time taken to complete the second 200m sprint test. Group 2 and 3 again showed an increase in time taken to complete the second sprint test post manipulation. iv It is, therefore, concluded that manipulation of a fixated cervical joint in asymptomatic kayakers results in an increase in performance, although it must be noted that these were only trends and that there was no statistical significance in these results. This research has, furthermore, opened the door to future studies which may test the performance enhancing benefits of competitive sports such as kayaking. / M
4

The immediate effect of thoracic spine manipulation on power output, speed and stroke rate in paddlers

Vivier, Thornton January 2016 (has links)
Submitted in partial compliance with the requirements for the Masters’ Degree in Technology: Chiropractic, Durban University of Technology, Durban, South Africa, 2016. / Background: Kayaking performance can be improved either through reducing drag of the boat or increasing propulsion (Michael et al., 2009). In order to increase propulsion, biomechanical efficiency is required. The trunk muscles have been highlighted as having an important role in the paddler’s stroke. Due to their relationship with the thoracic spine, dysfunction of the movement of the thoracic vertebrae could negatively impact the ability of the trunk muscles to work effectively. Spinal manipulation is used to restore joint range of motion and this has been shown to have a positive effect on the surrounding muscles. Limited studies have investigated the effect of spinal manipulation on performance outcomes, specifically in paddlers. Objective: To determine the effect of lower thoracic spine manipulation, of T7 - T12 vertebrae, compared to sham laser, on the mean power (watts) of a paddler’s stroke, the time taken (seconds) to paddle a 200m distance and stroke rate (strokes/min). Method: This study was designed as a pre-test, post-test experiment, involving 30 asymptomatic, male paddlers from Durban. Participants were divided into an intervention group, receiving spinal manipulation to the lower thoracic spine between T7 - T12 or a control group receiving sham laser. Participants performed a 200m sprint on a kayak ergometer followed by a timed five minute break, during which, the interventions were administered. This was followed by a second 200m sprint on the kayak ergometer post-intervention. Outcome measures were average power (watts), time taken to paddle a 200m sprint on a kayak ergometer (seconds) and stroke rate (strokes per minute). Conclusion: Lower thoracic spine manipulation did not result in a significant change in average power, time taken to paddle 200m on a kayak ergometer or stroke rate. Future studies are necessary to investigate the trends observed. / M
5

Effect of brief-intermittent hypoxic exposure on high-intensity kayaking and cycling performance

Bonetti, Darrell Unknown Date (has links)
Adaptation 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.
6

An investigation to identify changes in power of the kayaking stroke following manipulation of the cervical spine in asymptomatic kayakers

Cuninghame, Neil Mark January 2009 (has links)
Dissertation in partial compliance with the requirements for a Master's Degree in Technology: Chiropractic, submitted to the Faculty of Health at the Durban University of Technology, 2009. / Although kayaking is an Olympic sport and said to be one of the top ten growth sports in America, relatively little literature has been written on it by sports scientists and there is a paucity of available literature. Previous research has described the effects of spinal manipulation on muscles at distant sites to the joint being manipulated, and there have been trends which have shown a positive increase in strength and in muscle activity at these sites. There has, however, been a lack of literature to show that these positive trends would influence sporting performance in any way. 30 volunteer kayakers, who train and compete on a regular basis, were actively recruited and randomly allocated into one of three groups. Group 1 received manipulation on a fixated cervical segment, group 2 on a non-fixated cervical spine segment, and group 3 received placebo laser to the posterior cervical area. Subjects were then required to complete two 200m sprint tests on a kayak ergometer. Measurements were taken pre and post manipulation and included maximum watts recorded for the duration of the sprint test and time taken to complete 200m. Although no statistically significant results were found between the groups, trends revealed that in group 1, which received spinal manipulation on a fixated joint, there was an increase in the mean peak watts post manipulation, as compared to the placebo and non-fixated groups which showed a decrease in peak watts post manipulation. Group 1 also demonstrated a mean decrease in time taken to complete the second 200m sprint test. Group 2 and 3 again showed an increase in time taken to complete the second sprint test post manipulation. iv It is, therefore, concluded that manipulation of a fixated cervical joint in asymptomatic kayakers results in an increase in performance, although it must be noted that these were only trends and that there was no statistical significance in these results. This research has, furthermore, opened the door to future studies which may test the performance enhancing benefits of competitive sports such as kayaking.
7

Effect of brief-intermittent hypoxic exposure on high-intensity kayaking and cycling performance

Bonetti, Darrell Unknown Date (has links)
Adaptation 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.
8

The relationship between respiratory muscle fatigue, core stability, kinanthropometric attributes and endurance performance in competitive kayakers

Kroff, Jacolene 03 1900 (has links)
Thesis (MScMedSc (Biomedical Sciences))--University of Stellenbosch, 2005. / The purpose of this study was to determine the physiological and kinanthropometric attributes, respiratory muscle strength, and core stability of successful endurance paddlers, and to investigate the associations of these characteristics with kayak endurance performance in the laboratory and the field. Twenty male competitive paddlers (age: 28 ± SD 7 years, height: 184 ± SD 7 cm and weight: 80 ± SD 7 kg) were categorised in two ability groups, Elite and Sub-Elite. Testing included kinanthropometric measurements, maximum aerobic capacity, pulmonary function, six core stability tests, a 30 min endurance performance test (EPT) on the K1 Ergo and a 10 km time trial (TT) on the water. Maximum inspiratory mouth pressure (MIP) was measured before and after the 30 min EPT on the K1 Ergo to assess respiratory muscle fatigue. The Elite paddlers demonstrated significantly greater values for sitting height (as a percentage of stature), relative VO2max, PPO, PPO/kg, MVV and MIP compared to the Sub-Elite paddlers (All P < 0.05). They also demonstrated a significantly greater average PO and average back stroke length during the 30 min K1 Ergo EPT (P < 0.05) and a significantly faster race time (44:10 ± 1:17 vs 47:34 ± 3:14 min:s) during the 10 km water TT (P < 0.05), compared to the Sub-Elite paddlers. The paddlers did not experience respiratory muscle fatigue (as determined by change in MIP) after the 30 min K1 Ergo EPT. Significant intraclass correlations coefficients of r = 0.81 for average PO (30 min K1 Ergo EPT), r = 0.76 for MIP, and r = 0.95 for 10 km performance time, revealed the high repeatability of these tests. Significant relationships were found between the two endurance performance tests (30 min K1 Ergo EPT and 10 km water TT, r = -0.64, P < 0.05) and between both tests and a number of kinanthropometric, physiological and respiratory muscle function parameters. Stepwise multiple regression analysis revealed that PPO and MVV predicted endurance performance (average PO) on the K1 Ergo (R2 = 0.75, SEE = 15 W), whereas relative VO2max and best MIP predicted 10 km performance time on the water (R2 = 0.64, SEE = 115 s). The results of this study suggest that superior maximum aerobic capacities and respiratory muscle function distinguish successful paddlers from less successful paddlers and may be used to predict kayak endurance performance in the laboratory as well as on the water. No respiratory muscle fatigue occurred during the 30 min K1 Ergo EPT, indicating that respiratory muscle fatigue may not be a limiting factor to 30 min kayak endurance performance. The core stability results demonstrated no relevance to kayak endurance performance.
9

A Comparison of upper and lower limb exercise in canoeists using the heart rate and oxygen consumption relationship

Gomes, Adrian Neil. January 2003 (has links)
The heart rate achieved with maximal upper limb exercise is quoted as being on average thirteen beats per minute lower than when performing maximal leg exercise. Many canoeists use heart rate monitors during training and seek advice on setting their heart rate training zones. Existing guidelines are based on lower limb-derived heart rates, which may not be appropriate. As canoeists use predominantly their upper limbs during canoeing, it was hypothesized that as their upper limbs are trained, they may achieve heart rates and oxygen consumption similar to those achieved with lower limb exercise. The purpose of this investigation was to compare the relationship between heart rate and oxygen consumption when exercising on either a kayak ergometer or treadmill. Fifteen volunteer canoeists, who compete regularly, were recruited by convenience, purposive sampling and randomly allocated to a V02max test using open circuit spirometry, on either a kayak ergometer or treadmill. They returned within 5 to 7 days for a V02max test on the other apparatus. Their heart rates were also measured during these activities. The heart rate oxygen consumption relationship for upper and lower limb exercise was then analysed. Maximum heart rate was on average only 6 beats per minute lower with upper limb exercise, with some subjects achieving the same or very similar HRmax; the median difference in heart rate maximum was only 4 beats per minute. Although the response of heart rate and oxygen consumption to kayaking and running was similar at any given workload, the heart rate on the kayak was about 8 beats per minute higher at any submaximal workload. V02max. on the kayak was lower than on the treadmill. At any metabolic equivalent, the tidal volume was lower on the kayak and there was a lower respiratory rate on the treadmill. At any tidal volume, the metabolic equivalent was lower on the kayak ergometer. The minute volume on the kayak was higher than on the treadmill, for all but the highest intensities of exercise. Using the leg heart rate max to determine the training zones, a slightly higher (negligible) percentage of arm V0max is achieved at any given percentage heart rate. Kayakers who train regularly, appear to be able to attain similar maximum heart rates with upper and lower limb exercise, but a lower V02max when exercising with their arms. The heart rate oxygen consumption response is the same for upper and lower body exercise; and a reduced HRmax and increased heart rate at any sub maximal workload do not appear to apply to canoeists. It is therefore concluded that heart rate training zones based on leg HRmax are suitable for kayak training. This study has helped distinguish the difference between the heart rates of the upper and lower limbs at any given oxygen consumption in canoeists. The benefits of performing this study have also been to provide better advice to canoeists on how to train using heart rate monitors. / Thesis (M.Med.Sc.)-University of Natal, Durban, 2003.
10

The relationship between respiratory muscle fatigue, core stability, kinanthropometric attributes and endurance performance in competitive kayakers /

Kroff, Jacolene. January 2005 (has links)
Thesis (MSc)--University of Stellenbosch, 2005. / Bibliography. Also available via the Internet.

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