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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.
41

Relationships between sprint performance, power output and fatigue

Shorten, James 02 March 2010 (has links)
This investigation used a constant-load cycle ergometer as a way of examining relationships between the cycle ergometer and sprint performance. Twenty-five college-aged males were used for this investigation. Following a three minute warm-up, each subject performed a 15 sec. maximal bout on the cycle ergometer. The resistance load on the ergometer was set at 0.12kg/kg of bodyweight. Peak power (PP), average power (AP), time to peak power (TTPP), power fatigue rate (PFR), and power fatigue index (PFI) were computed using a microcomputer system. In addition, PP,AP, and PFR were adjusted for total bodyweight (PP/kg, AP/kg, PFR/kg). On a separate day each subject performed six sprints two each at 50m, 100m, and 200m. Each sprint was electronically timed using an infra-red motion detector and starting blocks were used. Initially low correlations were found between the ergometer parameters and the sprint times (r=.07-.55). However upon closer evaluation stronger relationships appeared to exist for the faster subjects. Therefore, subject subgroups of faster subjects were formed. Subject subgroups for the 5 Om (T<7.5sec.), 100m (T<l4sec.)}, and 200m (T<26.6sec.) showed higher correlations (r=.06-.70). Further analysis revealed that high inter-variable correlations existed between many of the ergometer variables. Based on these correlations the parameters were separated into four groups. Group I contained variables of absolute power (PP,AP), group II were variables of relative power (PP/kg, AP/kg), group III contained variables of fatigue (PFR, PFI, PFR/kg), and group IV consisted of the acceleration variable (TTPP). Equations for predicting sprint performance were developed using one to four variables with only one variable from each group being used. The best equation was considered to be the one that yielded the highest r* value while also yielding the lowest Akakai Information Criteria value and MSE. Variables from the relative power group (PP/kg, AP/kg) and fatigue group (PFR, PFI, PFR/kg) were the best indicators of performance. These results suggest that the cycle ergometer used in this investigation can be used for evaluating the components of sprint performance in untrained males, and that this test is best when compared to the 200 m dash. / Master of Science
42

The effect of wearing strength shoes during plyometric training on vertical jump performance

Jenkins, Karen M. 23 June 2009 (has links)
The purpose of this investigation was to determine whether plyometric training in Strength shoes (Strength Footwear, Inc.) increased vertical jump performance, decreased elapsed time in the 40 yard dash and increased calf circumference. Thirty-one male and female college-aged students served as subjects. Twenty-two subjects, enrolled in a college physical fitness class, were randomly assigned to one of two experimental conditions: Strength shoe (S) group or traditional shoe (T). A third condition, a control (C) group consisted of 9 volunteers enrolled in a college badminton class. Subjects in both experimental conditions trained for ten weeks, three times per week, 45 minutes per day. Subjects performed plyometric drills designed to increase vertical jump and increase running speed. Subjects were pre-tested and post-tested for vertical jump performance, speed in the 40 yard dash, and right and left calf circumference. There was no significant (p>. 05) change in either experimental group from pretest to post test on vertical jump performance, speed in the 40 yard dash and right and left calf circumference. It was concluded that, regardless of the footwear being worn, plyometric training did not increase vertical jump performance, calf circumference or decrease the elapsed time in the 40 yard dash of the participants. / Master of Science
43

Sprinting kinematics of athletes with selected physical disabilities

Andrews, Barry S. 04 1900 (has links)
Thesis (PhD(Sport Sc))--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The purpose of this research was to gain insight into the sprinting of athletes with selected physical disabilities. The sprint performances of four Paralympic athletes (T43, T13, T37 and T38 classifications) were analysed in terms of variability in the biomechanics of their set position and in the kinematics of the initial acceleration phase and the maximal acceleration phase of their 100m sprints. The athletes also reported their perceptions about the potential of a rhythm training programme to influence their sprinting. A case study approach was used. Sprint kinematics were video-recorded four times over the training year. DartFish ProSuite software supported the digital tagging of anatomical landmarks and the calculation of the biomechanical features of the set position as well as the kinematics of each athlete. A subjective log was used to gather their perceptions about the rhythm training programme. There was variability in all aspects for all four Paralympic athletes. This should encourage coaches to help athletes find optimal kinematics in relation to their disability, rather than trying to coach them to a set template of an ideal form. Based on the kinematic data collected over all four test sessions, it appears that a coaching focus on stride length was the key to faster sprinting for this T43 (amputee) athlete. A coaching focus on stride frequency (once optimal stride length had been discovered) was the key for the T13 sprinter (visually impaired), and a coaching focus on stride frequency was the key to faster sprinting for both the T37 and T38 athletes (cerebral palsy). Although all of the athletes enjoyed the rhythm training programme, only the least experienced athlete (T38) reported that he would like to continue with this form of training. / AFRIKAANSE OPSOMMING: Die doel van hierdie navorsing was om insig rakende die naellooptegnieke van atlete met geselekteerde fisiese gestremdhede te verky. Die naellooptegnieke van vier Paralimpiese atlete (T43, T13, T37 en T38 klassifikasies) is ontleed. Die ontleding is gedoen met betrekking tot die veranderlikheid in biomeganika tydens hul gereedheidsposisies in die wegspringblokke asook in die kinematika van die aanvanklike versnellingsfase en die maksimale versnellingsfase gedurende hul 100m naelloopitems. Die atlete het ook hul persepsies rakende ’n ritmiese oefenprogram wat potensieël hul naellope kon beïnvloed gerapporteer. ’n Gevallestudiebenadering is gebruik. Beeldmateriaal van naelloopkinematika is vier keer gedurende die oefenjaar vasgelê. “DartFish ProSuite” sagteware het die digitale kodering van anatomiese punte ondersteun asook die berekening van biomeganiese eienskappe gedurende die gereedheidsposisie en die kinematika van elke atlete gefasiliteer. Daar is op ’n subjektiewe basis boekgehou van die atlete se persepsies rakende die ritmiese oefenprogram. Daar was wisselvalligheid in alle aspekte met betrekking tot al vier Paralimpiese atlete. Dit behoort as aanmoeding vir afrigters te dien om atlete te help om optimale kinematika in verband met hul gestremdheid te vind, eerder as om die atlete volgens ’n vaste templaat of ideale vorm te probeer afrig. Volgens die kinematiese data wat oor die loop van al vier toetsingsessies ingesamel is blyk dit asof ’n afrigtingsfokus op treëlengte die sleutel tot vinniger naellope vir die T43- atleet (amputasie) was. ’n Afrigtingsfokus op treëfrekwensie (nadat optimale treëlengte bewerkstellig is) was die sleutel vir die T13-atleet (visueel gestremd) en ’n afrigtingsfokus op treëfrekwensie was die sleutel tot vinniger naellope vir beide die T37- en T38-atlete (serebrale gestremdheid). Alhoewel al die atlete die ritmiese oefenprogram geniet het, het slegs die mees onervare atleet (T38) aangedui dat hy met hierdie vorm van oefening sou wou aanhou.
44

Sprint analysis of athletes with intellectual impairments

Andrews, Barry 03 1900 (has links)
Thesis (M Sport Sc (Sport Science))--Stellenbosch University, 2008. / Intellectually impaired (II) athletes are not allowed to participate at the Paralympic Games because there is no accepted classification system for these athletes. The rationale for this study was to see if there are any physical differences existing in the sprint performance of II and non-II athletes and to see if there is a way to incorporate these differences into a new (accepted) classification system. The objective of this study was to identify any physical sources for the differences between II and non-II, with regard to the acceleration phase, the first 30m of the 60m sprint race, which could then be used in conjunction with other tests in the classification of II athletes. This new classification system might then allow II athletes to participate in the Paralympic Games again. 32 II athletes (22 male and 10 females) and 14 non-II athletes (10 males and 4 females) were used in this study. The sprint performance was analysed and compared of each athlete using the DartFish ProSuite software programme. The data collected from these analysis was then compared using the unpaired t-test, looking for any significant differences between the groups (p<0.05). From this analysis, it was concluded that stride length was the reason for the poorer performance of the II group when compared to the non-II group. Further research is required before definite conclusions can be made on the possible reasons for this difference.
45

The Effect of Hypoxic Training Upon the Speed of Sprint Freestyle in High School Competitive Swimming

Young, William Lee 08 1900 (has links)
This study investigated possible effects of hypoxic training upon speed of high school sprint freestyle. Thirty-eight subjects, grouped as their two schools, performed identical loads during the ten-week program. The Experimental group used hypoxic techniques for about one-half of each workout. Pretests and posttests conducted for the 50-yard and 100-yard distances yielded highly correlated mean scores, with marked differences between the two groups. Analysis of covariance was used, selecting the .05 level for rejection. The comparison of adjusted group means indicated neither group superior at 50 yards, while the 100-yard F-ratio was significant at the .0047 level favoring hypoxic training. It is recommended that hypoxic techniques be incorporated into existing programs, possibly benefitting other strokes.
46

Porovnání ročního tréninkového cyklu u vybraných českých elitních sprinterek / Comparison of the annual training cycle in the selected Czech elite women in sprinting

Vostatková, Pavlína January 2016 (has links)
Thema works: Comparison of the annual training cycle in the selected Czech elite women in sprinting Student: Pavlína Vostatková Supervisor: Dr. Aleš Kaplan, Ph.D. Aims: The aim of this study was to analyze the annual training cycle (RTC) in selected Czech elite women sprinters, in which the maximal performance in 100 m run was reached, and to compare the uniform training system and recommendations for sprinters of comparable level of performance with the reality of the training program of selected sprinters. The analysis focused on methodological procedure, application of selected special training indicators (STU), their volume and intensification in various stages of sports training. Methodology: The content analysis of training diary was used as a method of the thesis, in particular the annual training cycle, in which the sprinters achieved personal maxima in 100 m run. Thus RTC 1996/1997 and 1992/1993 in sprinter P. V. and H. B. were analyzed, respectively. In the training diaries selected general training indicators (OTU) and STU for sprinters in athletics were obtained and reviewed. Model values for the age category of 21-23 sprinters (Moravec, Hlína a kol., 1984) were used in the comparison of selected OTU and STU of the selected sprinters. The model values for the 19-year-old sprinter H. B....
47

Přehled různých forem rozcvičení před sportovním výkonem ve sprintu (literární rešerše) / An overview of the different forms of warm-up before athletic performance in sprinting

Zapal'ačová, Dominika January 2016 (has links)
Thema works: An overview of the different forms of warm-up before athletic performance in sprinting. Student: Bc. Dominika Zapaľačová Supervisor: PhDr. Aleš Kaplan Ph.D Aims: The aim of this thesis is the study of scientific and professional literature and articles to obtain information on warming up before speed sports performance represented by quick sprinting. It is also to consider how subsequent various kinds of warm up exercises can affect the sports performance mentioned above. Furthermore, to use a case study based on selected research methodology to measure the speed of running locomotion after the selected type of warming up. Methodology: A method of literary research is used in the thesis, primarily using foreign literature but Czech literature too, obtained mainly from online databases and subject bibliographies. Also the case study method was used to measure the speed of running locomotion. Results: Conducting literary research has proved that speed sports performance might be greatly affected by the selected method of warming up. Most of the mentioned authors state the positive influence of dynamic stretching and they also recommend eliminating static stretching before speed sports performance. Measuring the speed of running locomotion has proved that the probands did not show any...
48

An Investigation of the Sled Push Exercise: Quantification of Work, Kinematics, and Related Physical Characteristics

Hoffmann, James, Jr 01 August 2014 (has links)
The purpose of this dissertation was to describe the basic characteristics of performing resisted sprint training using a push sled for the enhancement of sport performance. Specifically, this dissertation served to: 1.) quantify the frictional forces involved between a push sled and an AstroTurf® surface at 6 loads, 2.) derive an estimation of mechanical work performed during sled push training, 3.) outline the velocity characteristics of 3 sled pushing loads scaled to the athletes body mass for comparison against their sprinting ability and 4.) determine the interrelations of fitness characteristics to the ability to sprint under heavy resistance. The following are major findings of this dissertation. 1.) Coefficients of static friction (0.53 – 0.37) and dynamic friction (0.35 – 0.28) were calculated at multiple loads for the AstroTurf® surface. 2.) A direct near perfect relationship exists between total system load of the sled and the forces required to initiate and maintain movement of the sled. Although a direct measurement of force would be more precise and account for changes in velocity, the total system load may be a more practical alternative for daily use. 3.) Statistically significant changes in velocity characteristics were observed within each sled pushing load as well as when comparing each load to sprinting. Decrements in peak velocity ranged from about 40%-51% when comparing resisted to unresisted sprinting. Load increments of 25% body mass were heavy enough to cause statistically significant differences in velocity characteristics. 4.) Statistically significant correlations were observed in anthropometry, sprinting ability, jumping ability, and strength to sled pushing. The results indicate that larger athletes, who can not only produce greater force but produce those forces rapidly, in addition to excelling at jumping and sprinting compared to their peers demonstrate the ability to move faster against heavy loads and slow down less from unresisted conditions. The strongest athletes demonstrated statistically nonsignificant differences in peak velocity drop off when compared to their weaker counterparts; however, small to moderate effect sizes (d = 0.27 – 1.02) were observed indicating a practical difference between strength levels in peak velocity and peak velocity drop off.
49

Assessing the validity of the zero-velocity update method for sprinting speeds

Pla, Gerard 01 September 2022 (has links)
INTRODUCTION: The zero-velocity update (ZUPT) method has become a popular approach to estimate foot kinematics from foot worn inertial measurement units (IMUs) for walking and running. However, it remains unknown how accurate the ZUPT method is for track sprinting speeds when using sensors with characteristics (i.e., higher ranges and sampling rates) better suited for sprinting. METHODS: 18 participants performed 70-meter track sprints while wearing a Blue Trident IMeasureU IMU. Two cameras, at 20 and 70 meters from the start, were placed to validate the ZUPT method on a stride-by-stride and on a cumulative distance basis. The validity of the method was assessed on: (1) A single stride attained at the end of the maximal speed phase, i.e., at 70m; (2) On a cumulative distance basis for the maximal speed phase from 20 to 70 meter; and (3) On total distance traveled for a 70-meter track sprint. RESULTS: Individual stride and cumulative distance errors remained within -8 to 3% and -4 to 2%, respectively. CONCLUSION: The results of this study demonstrate the ZUPT method is capable of yielding accurate estimates of stride length and cumulative distance traveled for sprinting speeds.
50

Mechanical power output and neuromuscular activity during and following recovery from repeated-sprint exercise in man

Mendez Villanueva, Alberto January 2005 (has links)
The purpose of the present study was to examine the time-course of mechanical power output and neuromuscular activity during fatiguing repeated-sprint exercise and recovery in man. Prior to the main study, we also investigated the reproducibility of power output during a single 6-s cycling sprint. For this study, eleven healthy moderately trained males performed a 6-s standing sprint on the front-access cycle ergometer on four separate occasions. The results of the study showed that reliable power outputs can be obtained after one familiarization session in subjects unfamiliar with maximal cycling sprint exercise. However, the inclusion of an extra familiarization session ensured more stable power outputs. Therefore, two trials should allow adequate familiarization with the maximal 6-s cycling test. For the main study, eight young moderately trained adult men performed an exercise protocol that consisted of ten, 6-s sprints on a wind-braked cycle ergometer interspersed with 30 s of recovery. After 6 min of passive recovery, five, 6-s sprints were repeated, again interspersed by 30 s of recovery. Peak power output (PPO) and mean power output (MPO) were measured during each sprint and EMG data (i.e., RMS) from the vastus lateralis muscle were also recorded. A one-way ANOVA with repeated measures (i.e., sprint number) was used to allocate the significant differences in each dependent variable over time. Analysis revealed a decline in power output during the fatiguing exercise that was accompanied by a decrease in EMG amplitude of the vastus lateralis muscle. Six minutes after the fatiguing exercise, power output during sprint 11 significantly recovered with respect to values recorded in sprint 10, but remained significantly lower than that recorded in the initial sprint. Thus, 6 min was insufficient to fully recover from the fatiguing repeated sprint protocol utilised in this study. The main findings in the present study were that: 1) the partial recovery of power output in sprint 11 was not accompanied by the recovery V of EMG amplitude; 2) similar mean power outputs were recorded during sprint 4 and 11 despite a significantly lower EMG activity recorded during the latter sprint; and 3) despite comparable mean power outputs during sprint 4 and 11, the decrease in power output over the next five sprints was greater for sprints 11 to 15 than for sprints 4 to 8.

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