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Effects of menstrual phase on performance and recovery in intense intermittent activityMiddleton, Laura Elizabeth. 10 April 2008 (has links)
This study examined differences and relationships between high intensity, intermittent work and menstrual phase. Six performed (10) 6-second sprints on a cycle ergometer in the luteal (LP) and follicular phase (FP) of the menstrual cycle. The average 6-second work was greater in the LP (39.3 (3.4)Jkg) than during the FP (38.3 (3.1)Jkg). There was no difference in peak 6-second power (6.8(0.6)W/kg in FP, 6.9(0.6)W/kg in LP) and the drop-off in work (1.2(3.5)J/kg in FP and 1.0(2.7)J/kg in LP) between menstrual phases. There was no significant difference in sprint V02 or recovery V02 between FP (2.3 (O.S)rnL/kg/min and 24.1 (2.5)mL/kg/min) and LP (2 1.8(1.6)mL/kg/rnin and 23.7(2.8)mL/kg/min). In sprints 2 to 10, recovery V02 was greater in LP (26.3(2.4)mL/kg/min) than FP (25.0(2.6)rnL/kg/min). Recovery V02 and average 6- second work positively correlated (0.78 in FP, 0.77 in LP). In summary, oxygen consumption between sprints 2-10 and average work was greater in LP than FP.
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Dietary intakes of eumenorrheic, oligomenorrheic, and amenorrheic endurance-trained runners and cyclistsMier, Constance, 1959- January 1989 (has links)
Specific dietary intakes were compared by menstrual status among endurance-trained athletes categorized as either eumenorrheic (EU) (N = 11), oligomenorrheic (OL) (N = 4) or amenorrheic (AM) (N = 5). It was hypothesized that nutrient intakes among endurance-trained women would be significantly different based on menstrual status. No significant differences in nutrient intakes were found among groups. The OL and the AM groups were significantly (p ≤ .05) younger than the EU group and the AM group had a significantly higher percent body fat when estimated by hydrostatic weighing (PFHW) than the EU group. Further comparisons of nutrient intakes were made between EU (N = 10) and AM (N = 4) runners. Zinc intake was significantly lower in the AM runners as compared to the EU runners. The AM runners were also significantly younger and had significantly higher PFHW than the EU runners. In conclusion, energy nutrient intakes appeared to not be significant factors in menstrual status. However, zinc intake was significantly lower (p ≤ .05) in AM runners as compared to EU runners.
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Bone mineral and menstrual cycle status in competitive female athletes : longitudinal studyRobinson, Tracey Leigh 02 May 1994 (has links)
Graduation date: 1994
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Faktore wat die prestasie en gesondheid van vroue-atlete kan beinvloedStrauss, Johannes Albertus de Wet 12 1900 (has links)
Dissertation (PhD)--University of Stellenbosch, 2003. / ENGLISH ABSTRACT: Although it is common knowledge that regular exercise has many beneficial effects on the
human body, it is also true that many highly competitive athletes neglect their health for the
sake of performance. With this as a general objective for the study, women athletes of the
Matie Athletics Club were recruited as subjects and were monitored and tested for several
health-related parameters.
Current results indicate that, although the average total cholesterol (TC) concentrations of the
group were within normal ranges, quite a number of the sprint and field athletes had TC
values regarded as a cardiovascular risk (> 5.2 mmol.l"). Serum testosterone levels of the
sprint and field athletes were also higher than those of the distance athletes, but a correlation
between TC and testosterone was not established. In general, cholesterol intake of women
athletes was within the recommended daily allowance (RDA) prescriptions. The high-density
lipoprotein fraction was also within the norm, but a better chemical pathological range had
been expected. All haematological parameters were within the normal ranges of distribution,
but the red blood cell count, haemoglobin concentration and hematocrit were on average
lower than the standard average for females. Athletes, quite often, have higher plasma
volumes than average and this can disguise normal haematological values and is described as
sport anaemia. The current study has also indicated an iron deficiency (83% RDA) in the diet
of female athletes in general. Thus the relatively low observed red blood cell count could not
necessarily be attributed to sport anaemia. The energy intake was also poor and did not
comply with the energy needs of the athletes. Bone mineral density (BMD) and plasma
electrolytes were normal. Distance athletes had a higher BMD of the hip compared to the
lumbar spine area. This is probably related to the stress to the hip associated with running. A
correlation was observed between TC and BMD of the hip of eumenorrheal and amenorrheal
athletes, which had not been observed before.
The influence of the phase of the menstrual cycle on the immune system is controversial, and
the results of the thesis confirm those of other studies that indicated no influence. In addition,
it has been shown that the exogenous ingestion of glutamine, before the onset of exercise, can
increase the plasma concentration thereof, and that the formerly observed decline (also seen in the current study) after intense exercise can be totally neutralized. This had not been
reported before. The physiological significance of this has not been established, but the
assumption is that a continuous adequate supply of glutamine will benefit the immune cells
with regard to its reaction to pathogens. As reported by others, it has been shown that the
ingestion of 5% glucose during long duration exercise eases the stress on the immune system,
as both leucocytes and cortisol levels were attenuated compared to intake of a placebo. A
new discovery, however, was that the ad libitum ingestion of glucose was not enough to
produce desired significant results. The importance of this finding may have practical
implications with regard to desirable amounts of glucose supplementation during races.
In conclusion: Female athletes of club performance level are on general in a healthy
condition, but are not excluded from the risk with regard to cholesterol. The screening of TC
alone is insufficient with regard to competitive athletes, unless the sub-fractions are screened
as well during routine medical examinations. Adjustments with regard to the energy and iron
content of the diet are suggested. Supplementation of glutamine and glucose before and
during exercise could be beneficial to the immune system. More studies with regard to the
association of cholesterol with BMD are recommended. / AFRIKAANSE OPSOMMING: Alhoewel dit algemeen bekend is dat oefening groot voordele vir die gesondheid van die
liggaam inhou, is dit ook so dat atlete wat hoogs kompeterend is hul gesondheid kan
verwaarloos ten koste van prestasie. Dit was die oorkoepelende doel van hierdie studie om
vroue-atlete van die Maties Atletiekklub as proefpersone te toets en te monitor vir verskeie
gesondheidsverwante parameters.
Huidige resultate dui daarop dat alhoewel die gemiddelde totale cholesterol (TC) van die
groep binne die normale grense was, 'n hele aantal van die naelloop- en veldatlete het TC
gehad wat oor die grens was wat as 'n risiko (> 5.2 mmol.l") vir kardiovaskulêre verwante
siektes beskou kan word. Serumtestosteroon-konsentrasie van die naelloop- en veldatlete
was ook hoër as dié van die langafstandatlete, maar dit het nie gekorrileer met TC nie. In die
algemeen was die cholesterolinname van vroue-atlete binne die aanbevole dieettoelaag
(ADT) voorskrifte. Die hoë-digtheid-lipoproteïenfraksie was ook binne die normale, maar
nie volgens verwagting in 'n meer gunstige chemies-patalogies gebied van verspreiding nie.
Alle hematologiese parameters was binne die normale grense, maar die gemiddelde
rooibloedseltelling en hemoglobienkonsentrasie, asook die hematokrit was deurgaans laer as
die standaard gemiddeld vir dames. Atlete het heel dikwels hoër plasmavolumes as normaal
en dit kan normale hematologiese tellings verbloem en word beskryf as sportanemie. Die
huidige studie het egter ook getoon dat 'n ystertekort (83% ADT) in die dieet algemeen in
vroue-atlete kan voorkom en daarom kan die relatief lae rooiseltellings nie noodwendig aan
sport anemie toegeskryf word nie. Die energie-inname was ook laag en het nie aan die
energiebehoeftes voorsien nie. Beenmineraaldigtheid (BMD) en plasma-elektroliete was
normaal. Langafstandatlete het 'n hoër BMD van die heupbeen teenoor die werwelkolom
getoon wat waarskynlik verband hou met die stres wat deur hardloop op die heupbeen
geplaas word. 'n Verband is ook gevind tussen die BMD van die heup en TC van
eumenorreale en amenorreale atlete wat nie vantevore waargeneem is nie.
Die invloed van die fase van die menstruale siklus op die immuunstelsel is kontroversieel en
die bevindinge in die tesis dra by tot die stawing van studies wat geen invloed bevind het nie.
Voorts is getoon dat die eksogene inname van glutamien voor die aanvang van oefening, plasmaglutamien kan verhoog en dat die verlaging daarvan, wat voorheen (asook in die
huidige studie) na intense oefening waargeneem word, geheel en al teengewerk kan word.
Dit is nog nie vantevore waargeneem nie, en mag 'n fisiologiese voordeel inhou vir die
immuunselle ten opsigte van hul reaksie op patogene. Dit is huidig, ook soos voorheen,
aangetoon dat die inname van 5% glukose tydens langdurige oefening die stres wat op die
immuunsisteem geplaas word, verminder word. Dit, omrede beide die leukosiete en
kortisolkonsentrasies laer was in vergelyking met 'n plaseboproefneming. 'n Nuwe
bevinding is egter dat die onvoorgeskrewe inname van glukose nie genoegsaam is om
dieselfde insiggewende resulaat te toon nie. Die belang van hierdie bevinding mag praktiese
gevolge hê vir die gewenste voorskrifte van glukose-inname tydens wedlope.
In opsomming: Vroue-atlete van klubprestasiegehalte is oor die algemeen gesond, maar is
nie vrygespreek van risiko in terme van cholesterol nie. Die monitering van TC alleenlik is
onvoldoende in kompeterende atlete en die subfraksies moet derhalwe deel wees van roetine
ondersoeke. Dieetaanpassings ten opsigte van die energie- en ysterinhoud kan aanbeveel
word. Supplementasie van glutamien en glukose voor en tydens oefening respektiewelik, kan
voordelig wees vir die immuunsisteem. Verdere studies word aanbeveel in terme van die
verbande tussen cholesterol en BMD.
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A comparison of the power vs. time curves of cycle ergometer and ariel dynamometer in female athletesSpeth, Stephanie Y. (Stephanie Yasmin) January 1994 (has links)
The purpose of this study was to examine power output and fatigue from power-time curves of cycle ergometer and isokinetic dynamometer tests. Fifteen physically active female university athletes performed a 45 s cycle ergometer test at resistances of 0.075, 0.085, and 0.095 kp/kg bw, as well as a 45 s and a 3 repetition isokinetic flexion and extension test at velocities of 60, 180, and 300$ sp circ$/s. Results revealed that peak power, mean power (W and W/kg), and fatigue (W/kg) were highest at the 0.095 kp/kg bw resistance and lowest at the 0.075 kp/kg bw resistance. Significant differences among the three cycle ergometer conditions existed for peak power, mean power, and fatigue. Peak power and mean power (W and W/kg) were highest at 300$ sp circ$/s and lowest at 60$ sp circ$/s. Results revealed significant differences among the isokinetic dynamometer conditions for peak and mean power. Mean power output (W) was significantly correlated (range of r = 0.56 to r = 0.74) for the cycle ergometer and the isokinetic dynamometer test conditions.
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The oxygen cost of horizontal and grade running on the treadmill with female runnersTzavellas, Georgia January 1994 (has links)
The purpose of this study was to examine the vertical component of the American College of Sports Medicine (A.C.S.M.) Guidelines equation to predict the oxygen cost of grade running. The A.C.S.M. Guidelines equation is: VO$ sb2$(ml/kg.min) = 3.5 + 0.2 speed(m/min) + 0.9 (speed(m/min) * grade(frac)). Twenty-three female runners (20 to 33 years) participated in (1) a VO$ sb2$max test, (2) five 6 min running economy (RE) tests at 133 m/min, (3) five 6 min RE tests at 160 m/min, and (4) three 6 min RE tests at 186 m/min. The RE tests at 133 and 160 m/min were performed at the following grades: 0, 2.5, 5.0, 7.5, and 10.0%. The RE tests at 186 m/min were performed at 0, 2.5, and 5.0% grade. The RE tests were administered in random order. There was a linear relationship between VO$ sb2$ and horizontal running velocity with a slope of 0.20 ml/kg.m (r = 0.996; p $<$.01). There was a linear relationship between VO$ sb2$ and percent grade when running on a treadmill. The correlations for the regression equations at speeds of 133, 160, and 186 m/min were 0.90 (p $<$.01), 0.86 (p $<$.01), and 0.73 (p $<$.01), respectively. Inclusion of a grade component in the regression analysis equation increased the accuracy for predicting the VO$ sb2$ of grade running. VO$ sb2$ consumption for grade running can be predicted using the following equation: VO$ sb2$ (ml/kg.min) = 3.5 + 0.198(speed in m/min + 0.932 grade(%)) + 0.006(speed(m/min) * grade(%)). The new equation explained 99.5% of the variance (R$ sp2$) compared to the 78.0% of the variance (R$ sp2$) that was explained by the A.C.S.M. Guidelines equation.
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A comparison of the power vs. time curves of cycle ergometer and ariel dynamometer in female athletesSpeth, Stephanie Y. (Stephanie Yasmin) January 1994 (has links)
No description available.
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The oxygen cost of horizontal and grade running on the treadmill with female runnersTzavellas, Georgia January 1994 (has links)
No description available.
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Men and women in hypoxia : the influence of tissue oxygenation on repeated-sprint abilitySmith, Kurt, University of Lethbridge. Faculty of Arts and Science January 2010 (has links)
This thesis examined the impact of oxygen (O2) availability on prefrontal cortex and muscle tissue oxygenation during repeated-sprint exercise (RSE) in men and women. Men and women matched for initial-sprint mechanical work performed during ten, 10-s sprints (30s of rest) in normoxia (21% FIO2) and acute hypoxia (13% FIO2). Mechanical work and arterial O2-saturation (SPO2) were obtained for every sprint. Oxy- and deoxygenated haemoglobin concentrations (O2Hb, HHb) were obtained via near-infrared spectroscopy. Hypoxia elicited lower SPO2 and work (14.8% & 7.4%, P < 0.05), larger (45.1%, P < 0.05) and earlier reductions in cortical oxygenation, and no differences between sexes. Cortical de-oxygenation and work decrement were strongly correlated (R2=0.85, P < 0.05). Muscle de-oxygenation was greater in men than women (67.3%, P < 0.05). These results show that O2 availability influences cortical oxygenation and performance equally in men and women, and suggest a more efficient muscle O2 uptake in women. / ix, 108 leaves : ill. ; 29 cm
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The ergonomics of wheelchair configuration for optimal sport performanceMason, Barry S. January 2011 (has links)
No description available.
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