Syfte och frågeställningar | Undersöka sambandet mellan kardiovaskulär kondition och skärmtid, samt undersöka skillnader i kardiovaskulär kondition samt skärmtid hos ungdomar med Attention Deficit Hyperactivity Disorder (ADHD) och hur det skiljer sig från ungdomar utan ADHD. Frågeställningar: 1. Hur skiljer sig kondition (beräknad VO2max) hos ungdomar med och utan ADHD? 2. Hur skiljer sig skärmtid hos ungdomar med ADHD från ungdomar utan ADHD? 3. Hur ser sambandet ut mellan skärmtid och kondition hos ungdomar med samt utan ADHD diagnos?  Metod | Studien inkluderar 1139 ungdomar från 34 skolor i åldersspannet 13–14 år. Studien är en tvärsnittsstudie som är en del av en större studie ”Physical Activity for Healthy Brain Functions in School Youth” genomförd 2019 baserad på kvantitativ data där kardiovaskulär kondition uppskattades i ml/kg/min efter utfört Ekblom-Bak submaximala cykel ergometer test. Skärmtid samt allmän beskrivande data (kön, ålder, vikt och längd) baserades på enkätfrågor och inhämtad data från SCB kring socioekonomisk bakgrund.  Resultat | Resultaten visade ingen signifikant skillnad i VO2max (ml/kg/min) mellan ungdomar med ADHD och utan ADHD (p = 0.333). Vid kontroll av kön, föräldrautbildning och BMI kunde en signifikant skillnad visas (β = -3.398 ml/kg/min, p = 0.014). Vid analys av skillnader i skärmtid under en vanlig vardag och en vanlig helgdag var inte skillnaden signifikant mellan ungdomar med ADHD och utan ADHD (vardag p = 0.269, helgdag p =0.275). Det fanns ett signifikant samband hos ungdomar utan ADHD vid uppskattad VO2maxoch skärmtid vardag 3–4 timmar (β = -1.993 ml/kg/min, p &lt;0.001), vardag ≥5 timmar (β = -2.066 ml/kg/min, p = 0.004), helgdag ≥5 timmar (β = -2.244 ml/kg/min, p = 0.003) jämfört med referens 0–2 timmar. För ungdomar med ADHD kunde inget signifikant samband för samtliga kategorier av skärmtid utläsas (p = 0.786, p = 0.060, p = 0.392, p = 0.806).  Slutsats | Denna studie påvisar en signifikant skillnad i VO2max mellan ungdomar med och utan ADHD, medan ingen signifikant skillnad i skärmtid observerades. Uppmätt signifikant samband mellan kardiorespiratorisk kondition och skärmtid en vanlig vardag ≥3, samt skärmtid en vanlig helgdag ≥5 timmar hos ungdomar utan ADHD kunde tydas. Däremot sågs inget sådant samband hos ungdomar med ADHD. Ytterligare forskning föreslås med större stickprov på ungdomar med ADHD samt kontroll av diagnos och medicinering. / Aim | To investigate the associations between cardiorespiratory fitness and screen time, also investigate the differences in cardiorespiratory fitness as well as screen time for adolescents with Attention Deficit Hyperactivity Disorder (ADHD) and how it differs from adolescents without ADHD. Questions posed: 1. How does cardiorespiratory fitness (calculated VO2max) differ in adolescents with and without ADHD? 2. How does screen time differ for adolescents with ADHD compared to adolescents without ADHD? 3. What are the associations between screen time and cardiorespiratory fitness based on adolescents with and without ADHD diagnosis? Method | The study included 1139 adolescents from 34 schools in the age range 13–14. This is a cross- sectional study as a part of the larger study ”Physical Activity for Healthy Brain Functions in School Youth” conducted 2019 based on quantitative data where cardiorespiratory fitness was estimated in ml/ kg/ min after performing the Ekblom-Bak cycle ergometertest. Screen time and general descriptive data (gender, age, weight and height) were based on survey questions and obtained data from SCB concerning socioeconomic background.  Results | No significant difference in VO2max (ml/kg/min) between adolescents with ADHD and without ADHD (p = 0.333). When controlled for gender, parental education and BMI, a significant difference could be established (β = -3.398 ml/kg/min, p = 0.014).Analysis of differences in screen time during a normal weekday and weekend day was not significant between adolescents with ADHD and without ADHD (weekday p = 0.269, weekend day p = 0.275). There were a significant association in adolescents without ADHD with estimated VO2max and screen time weekdays 3–4 hours (β = -1.993 ml/kg/min, p &lt;0.001), weekday ≥5 hours (β = - 2.066 ml/kg/min, p = 0.004), weekend day ≥5 hours (β = -2.244 ml/kg/min, p = 0.003) from the reference 0–2 hours. For adolescents with ADHD, no significant association was seen for any category of screentime (p = 0.786, p = 0.060, p = 0.392, p=0.806). Conclusions | This study showed significant difference in VO2max between adolescents with and without ADHD, however no significant difference in screen time was observed. Significant measured association between cardiorespiratory fitness and screen time on an iiiordinary weekday ≥3, such as screen time on an ordinary weekend day ≥5 h in adolescents without ADHD was shown. However, no such association was seen for adolescents with ADHD. Further research with a larger population in adolescents with ADHD and controlling for diagnosis and medication is necessary. / <p>Uppsatsen tilldelades stipendiemedel ur Överste och Fru Adolf Johnssons fond 2023.</p>

The purpose of this study was to develop a regression equation to predict VO2max based on non-exercise (N-EX) data. All participants (N = 100), aged 18-65 years old, successfully completed a maximal graded exercise test (GXT) to assess VO2max (mean ± SD; 39.96 mL∙kg-¹∙min&sup-1; ± 9.54 mL∙kg-¹∙min-¹). The N-EX data collected just before the maximal GXT included the participant's age, gender, body mass index (BMI), perceived functional ability (PFA) to walk, jog, or run given distances, and current physical activity (PA-R) level. Multiple linear regression generated the following N-EX prediction equation (R = .93, SEE = 3.45 mL∙kg-¹∙min-¹, %SEE = 8.62): VO2max (mL∙kg-¹∙min-¹) = 48.0730 + (6.1779 x gender) - (0.2463 x age) - (0.6186 x BMI) + (0.7115 x PFA) + (0.6709 x PA-R). Cross validation using PRESS (predicted residual sum of squares) statistics revealed minimal shrinkage (Rp = .91 and SEEp = 3.63 mL∙kg-¹∙min-¹); thus, this model should yield acceptable accuracy when applied to an independent sample of adults (aged 18-65) with a similar cardiorespiratory fitness level. Based on standardized β-weights the PFA variable (0.41) was the most effective at predicting VO2max followed by age (-0.34), gender (0.33), BMI (-0.27), and PA-R (0.16). This study provides a N-EX regression model that yields relatively accurate results and is a convenient way to predict VO2max in adult men and women.

Carotid intima-media thickness (cIMT) is a valid measure of cardiovascular disease (CVD). Physical activity appears to improve cIMT, however, research is inconclusive. This study investigated the relationship between physical activity (physical activity rating (PA-R)) and cardiovascular fitness (predicted VO2max , perceived functional ability (PFA)) and cIMT. Data collected from 341 seniors (≥50 years) competing in the Huntsman World Senior Games (HWSG) included blood lipids, inflammatory makers, blood glucose, blood pressure (BP) and anthropometric measurements of obesity and central adiposity. Multiple regression analysis was used to determine correlations of measured variables with cIMT. Two of the fitness related variables, PFA (r ≈ 0.1359; p = 0.012) and predicted VO2max (r ≈ 0.1475; p = 0.007) were significantly correlated to cIMT without controlling for confounding factors, but lost significance when adjustments for other CVD risk factors were included. PAR (r ≈ 0.0869; p = 0.111) was not significantly correlated to cIMT. Regression analysis indicated that the most predictive variables of cIMT we investigate were: age (t = 7.166, p = 0.000), gender (t = 3.310, p = 0.001), BMI (t = 1.892, p = 0.05), SBP (t = 3.952, p = 0.000), total cholesterol (TC) (t = 4.184, p = 0.000) and triglycerides (TRG) (t ≈ 3.466, p = 0.000), our R2 = .299, thus indicating these 6 variables account for about 30% of the variance in cIMT in seniors competing at HWSG. Physical activity and cardiovascular fitness influence other CVD risk factors and consequently may have an indirect impact on cIMT.

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No description available.

The aim of this thesis was to investigate the extent of peripheral and central components in the development of fatigue during maximal exercise. Fatigue during maximal and supramaximal exercise has traditionally been modelled from the peripheral context of an inadequate capacity to supply metabolic substrate to the contracting muscles to meet the increased energy demand. However, there are a number of observations that are not compatible with the peripheral fatigue model but which support a reduced central drive during exercise acting to prevent organ failure that might occur should the work be continued at the same intensity. Candidates for the role of “exercise stopper” have been identified as mechanical forces, teleoanticipation, cardiovascular capacity and dyspnoea. We explored these various possibilities in order to determine the most likely cause of exercise cessation during high intensity exercise.The development of a plateau in oxygen consumption during maximal incremental exercise has traditionally been used as evidence that an oxygen deficiency in the exercising muscles causes the termination of exercise. However, the incidence of this “plateau phenomenon” depends largely on mode of exercise, testing protocol and sampling frequency. The aim of this study was to examine whether the development of the “plateau phenomenon” is an artefact of pedalling cadence. In the first study nine healthy individuals performed in random order a maximal incremental ramp test (0.5 W.s-1) on four occasions at a fixed cadence of 60, 80 or 100 rpm and at a self-selected cadence. Oxygen consumption (VO2), CO2 production (VCO2), minute ventilation (VE) and heart rate were measured throughout each trial and averaged over 30 s. Cadence was recorded every second. Neither VO2max nor peak power output were different between trials. Submaximum VO2, VCO2 and VE were not influenced by cadence. A plateau in oxygen consumption was observed in 14% of the trials. Cadence declined significantly towards the end of the self-selected cadence trial (p < 0.05). This ramp protocol produces a low incidence of the “plateau phenomenon” and the measured physiological variables are unaffected by cadence. Furthermore, only one subject displayed this phenomenon on more than one occasion. This confirms that the “plateau phenomenon” is an artefact of the testing protocol. The significant fall in cadence in anticipation of exercise termination during the self-selected cadence trial indicates the presence of a neural regulation, which would lead to a “plateau phenomenon” in those cycle tests in which the work rate is cadence-dependent.The purpose of the second study was to assess whether pacing strategies are adopted during supramaximal exercise bouts lasting longer than 30 s. Eight healthy males performed six Wingate Anaerobic Tests (WAnT). Subjects were informed that they were performing four 30 s WAnT and a 33 s and 36 s WAnT. However, they actually completed two trials of 30, 33 and 36 s each. Temporal feedback in the deception trials was manipulated so that subjects were unaware of the time discrepancy. Power output (PO) was determined from the angular displacement of the flywheel and averaged over 3 s. The peak power (PPI), mean power (MPI) and fatigue (FI) indices were calculated for each trial. Power output was similar for all trials up to 30 s. However, at 36 s the PO was significantly lower in the 36 s deception trial compared to the 36 s informed trial (392 ± 32 W vs 470 ± 88 W) (p < 0.001). The MPI was significantly lower in the 36 s trials (714 ± 76 W and 713 ± 78 W) compared to the 30 s trials (745 ± 65 W and 764 ± 82 W) although they were not different at 30 s (764 ± 83 W and 755 ± 79 W). The significant reduction in FI was greatest in the 36 s deception trial. In conclusion, the significant reduction in PO in the last six seconds of the 36 second deception trial, but not in the 36 second informed trial, indicates the presence of a pre-programmed 30 second “end point” based on the anticipated exercise duration from previous experience. Furthermore the similarity in pacing strategy in all informed trials suggests that the pacing strategy is centrally regulated and is independent of the total work to be performed.Athletes adopt a pacing strategy to delay fatigue and optimise athletic performance. However, many current theories of the regulation of muscle function during exercise do not adequately explain all observed features of such pacing strategies. We studied power output, oxygen consumption and muscle recruitment strategies during successive 4km cycling time trials to determine whether alterations in muscle recruitment by the central nervous system could explain the observed pacing strategies. Seven, highly trained cyclists performed three consecutive 4 km time trial intervals, each separated by 17 minutes. Subjects were instructed to perform each trial in the fastest time possible, but were given no feedback other than distance covered. Integrated electromyographic (iEMG) readings were measured at peak power output and for 90 s before the end of each trial. Subjects reach a VO2max in each interval. Time taken to complete the first and third intervals was similar. Peak power output was highest in the first interval but average power output, oxygen consumption, heart rate and postexercise plasma lactate concentrations were not different between intervals. Power output and iEMG activity rose similarly during the final 60 s in all intervals but were not different between trials. The similar pacing strategies in successive intervals and the parallel increase in iEMG and power output towards the end of each interval suggests that these pacing strategies could not have been controlled by peripheral mechanisms. Rather, these findings are compatible with the action of a centrally regulated that are recruited and de-recruited during exercise. The extent to which peripheral feedback influences recruitment patterns could not be determined from these experiments.The fourth study examined whether the supplementation of inspired air with a hyperoxic mixture results in a dose-dependent increase in peak work rate and maximal oxygen consumption (VO2max) during a ramp test to volitional exhaustion. To avoid the methodological disadvantages associated with breathing the gas mixtures from mixing bags, the trials were performed in a sealed chamber in which the oxygen fraction (FIO2) in the ambient air was altered and subjects were able to inhale directly from the environment. The three oxygen fractions in which the subjects exercised were 21% (room air), 35 or 60%. Arterial blood sampling occurred at rest and every 3 min during the trial. The blood was analysed for the partial pressure of oxygen (pO2), and carbon dioxide (pCO2); pH; oxygen saturation (sO2); haemoglobin saturation (O2Hb); and lactate concentrations. Expired gas and heart rate were measured continuously. Arterial sO2 and O2Hb were elevated in both hyperoxic conditions and did not fall throughout either trial. However in the normoxic trial sO2 and O2Hb declined over the duration of the trial. Lactate concentrations and pH were similar between all trials. VO2max was significantly higher with an FIO2 of 35 and 60% but was not different between hyperoxic conditions. Maximal ventilation (VEmax), carbon dioxide production (VCO2max) and heart rate were similar for all trials. Peak power output was increased in the trained athletes in the 60% FIO2 trial. Since the plateau phenomenon occurred infrequently in all trial (~9%) and the effect of hyperoxia on performance was less than the changes in blood oxygen carrying capacity, we conclude that hyperoxia improved exercise performance not solely by increasing oxygen delivery to the exercising muscles.In order to be able to directly compare the results from studies using different equipment it is important to know the interchangeability of the results from the machines. The fifth study tested the reliability and interchangeability of the two automated metabolic gas analyser systems that would be used in this series of studies at a range of submaximal workloads. Eight highly trained cyclists performed two incremental submaximal cycle ergometer tests. For each session either a Schiller CS-200 or a Vmax Series 229 automated gas analyser was used for expired gas analysis. Data for oxygen consumption (VO2), CO2 production (VCO2), minute ventilation (VE) and respiratory exchange ration (RER) were averaged for each of the five stages (200, 250, 275, 300 and 325 W). The VO2, VE and RER were similar between trials at all workloads. However, VCO2 was significantly lower in the Schiller trial at workloads above 200 W (p < 0.05). Although there was a significant correlation between the two automated systems for the measured parameters (VO2 = 0.78; VCO2 = 0.80; VE = 0.82; RER = 0.72) (p < 0.05), a Bland-Altman plot revealed that the limits of agreement between the two systems were unacceptably large (VO2 = 0.53 to 1.30 L.min-1; VCO2 = 0.55 to 0.64 L.min-1; VE = -22.3 to 30.3 L.min-1; RER = - 0.03 to 0.13). The co-efficient of variation within the analysers was insignificant for both systems. Both the systems provide reliable measures of expired gas parameters. However, care should be taken in directly comparing studies that have used the two different systems due to the poor agreement between the systems.The factors causing the termination of maximal exercise at sea level are unknown. A widely held view is that skeletal muscle anaerobiosis consequent to an inadequate oxygen delivery to the exercising muscles limits exercise. However, there is also evidence that respiratory muscle fatigue at the high ventilatory volumes achieved during maximal exercise delivery and respiratory muscle work on maximal exercise performance, we exercised 8 highly trained cyclists in a pressure-sealed chamber in which O2 concentrations were manipulated and helium (He) was substituted for nitrogen in the ambient air in order to reduce the work of breathing during exercise. This system ensured that external inspiratory and expiratory resistance was minimised and identical in all experimental conditions and approximated conditions present during usual exercise. During trials with O2 enriched ambient air the peak work rate increased (451 ± 58 W vs. 429 ± 59 W). Neither maximum nor submaximal oxygen consumption was altered in FIO2 of 35% (5.0 ± 0.6 l.min-1) compared to 21% (4.9 ± 0.7 l.min- 1). Substituting helium for nitrogen had no additional effect on work (453 ± 56 W) or VO2max (4.9 ± 0.7 l.min-1) beyond those observed for the hyperoxic conditions. Although submaximum VE was reduced with helium, VEmax was unchanged. Since exercise was terminated at the same peak work rate (± 5 W) in the two hyperoxic conditions we postulate that the actual work rate may be the sensed variable that determines maximal exercise performance. The findings from these studies suggest that the maintenance of physiological homeostasis and the avoidance of organ and cellular damage are of fundamental importance during maximal exercise. This is achieved through central regulation of work output based, possibly, on afferent information from the mechanoreceptors in the exercising skeletal muscles or alternatively, the extent of motor unit recruitment during maximal exercise may be hardwired in the central nervous system in a system of feed-forward control.

Title: Functional Profile of Performance Billiard Players Objectives: The main aim of thesis was to find out maximal functional characteristics and body composition of performance billiard players by using laboratory testing. Next step was to define load intensity during simulated match. Methods: There were used biomedical measurements as a body measuring, bioelectrical impedance, laboratory spiroergometric measuring by maximal stress testing. Field spiroergometric measuring was provide during simulated match in pool hall. To find the role of physical fitness in performance billiard were used half structured interview with open questions and online survey. Results: The findings show that tested billiard players achieve levels of physical fitness from average to very good values. But some of them are classified as overweight and obese. Long-time playing billiard does not have any important influence on asymetric composition of muscle mass of upper limbs. During playing billiard an oxygen consumption didn't get over 30% of VO2max and values of heart rate were between 39 to 59% HRmax. During playing billiard an energy expenditure grows from 222 to 330% of BM. Billiard energetic demands of tested players are moving between 14,6 kJ to 29,3 kJ. Another result of thesis is a statement about the role of...

Syfte och frågeställningar. Syftet med studien är att, hos äldre personer, över 65 år, samt hos yngre vuxna, mellan 20-30 år, jämföra syreupptagningsförmågan med två olika metoder, fem-minuterspyramidtest (5MPT) samt VO2max-test på löpband. Vid båda mätmetoderna används direkt syrgasmätning. Metod. Totalt deltog 36 personer i studien, varav 17 äldre personer 65 till 85 år (9 kvinnor och 8 män) samt 19 yngre med en ålder mellan 20 till 35 år (10 kvinnor och 9 män). Deltagarnas syreupptagningsförmåga mättes under 5MPT vid två tillfällen som sedan jämfördes med VO2max mätt via ett maximalt test på löpband vid ett tillfälle. Således utfördes sammanlagt tre mätningar med direkt syrgasmätning, via andningsmask, under ett maximalt löpbandstest samt under två separata tester av 5MPT med minst 48 timmar mellan varje testtillfälle. Utandningsluften analyserades sedan, vid 5MPT för alla, via det trådlösa portabla systemet Jaeger Oxycon Mobile och vid test på löpband för testgruppen med yngre deltagare. För den testgrupp med äldre deltagare användes, vid testet på löpband, den fasta on-line-utrustningen Jaeger Oxycon Pro som är en liknande mätmetod för syreupptag. 5MPT är ett fem minuter långt test där individen från golvnivå, med högsta möjliga tempo, förflyttar sig fram och tillbaka på en 5,50 meter lång sträcka med en centralt placerad trappramp som är pyramidformad och med en högsta central höjd på 0,62 meter. Resultat. Det primära fyndet i studien var att en stark signifikant korrelation (r = 0,99) visade sig mellan direkt uppmätt VO2max under maximalt test på löpband gentemot syreupptagningsförmågan vid 5MPT då båda åldersgrupperna var sammanslagna, uppmätt i l·min–1. Slutsats. Då det i undersökningen visades en stark signifikant korrelation mellan direkt uppmätt VO2max vid 5MPT och ett maximalt test på löpband i l·min–1 för äldre och yngre vuxna ger det indikationer på att 5MPT kan används som en tillförlitlig metod vid undersökning och uppföljning av en persons aeroba förmåga. Fyndet kan vara av värde då det genom mindre kostsamma och enklare metoder går att få ett mått på en persons hälsa i form av aerob kapacitet, vilket är betydelsefullt ur flera hälsoaspekter på individ- och samhällsnivå. / Aim. The purpose of the study was to investigate the results and correlation between oxygen uptake levels (VO2max) at five-minute pyramid test (5MPT) against maximal oxygen uptake test (VO2max) on a treadmill test, both measured by direct oxygen measurement, in elderly people over 65 years and younger adults aged 20-30 years. Method. A total of 36 people participated in the study, 17 elderly people aged between 65 to 85 years (9 women and 8 men) and 19 younger adults aged between 20 to 35 years (10 women and 9 men). The participants' oxygen uptake was measured twice during 5MPT and then compared with VO2max measured by a maximal treadmill test at one occasion. Thus a total of three measurements with direct oxygen measurement, via the breathing mask, during a maximum treadmill test and two separate tests of 5MPT with at least 48 hours between each test. The exhaled air was analyzed at 5MPT for all, through the wireless portable system Jaeger Oxycon Mobile and also during the test on treadmill for the test group with younger participants. The test group of older participants, got their exhaled air analyzed through a stationary on-line equipment Jaeger Oxycon Pro instead of the portable system which is a similar reliable method to measure VO2max. 5MPT is a five minute test where the subjects from floor level, with the highest possible speed, moves back and forth at a measured distance of 5.50 meter with a central staircase ramp, which is pyramid-shaped, with a maximum center height of 0.62 meters. Results. The main finding of the study was that there was a strong significant correlation (r = 0.99) between directly measured VO2max during a maximum treadmill test compared to oxygen uptake at 5MPT when both the elderly people and the younger adults were combined, measured in l·min–1. Conclusion. The study showed a strong significant correlation between directly measured VO2max at 5MPT and a maximal treadmill testing l·min–1 for older and younger adults. This indicates that 5MPT can be used as a reliable method for investigation and monitoring a person’s aerobic capacity. This finding may be of value because it shows that less expensive and easier methods can be used to measure a person's health in terms of aerobic capacity, which is important from several aspects of health at both the individual and society level.

Syfte och frågeställningar Syftet med studien var att undersöka för elitorienterare resultaten vid och korrelationen mellan ett så kallat 5 minuters pyramidtest (5MPT) och ett maximalt test för bestämning av maximalt syreupptag (VO2max) på rullband. Frågorna vi ställde oss var: Vilken korrelation föreligger mellan 5MPT och ett bestämt VO2max på rullband hos elitorienterare? Hur ser en jämförelse ut mellan uppmätt samt beräknat VO2max? Vilken är reliabiliteten för 5MPT? Hur ser ekvationen ut för att beskriva sambandet mellan dessa två olika maxtester? Metod I valideringsstudien deltog 16 elitorienterare (6 kvinnor och 10 män) i åldrarna 17 till 37 år. De två testerna som genomfördes var 5MPT och bestämning av VO2max på rullband. 5MPT är ett skytteltest som är fem minuter långt, där testpersonen (tp) tar sig fram och tillbaka mellan två stolpar (sträcka 5.5 m) där en vertikal trappa (formad likt en pyramid) passeras under varje vända. Antalet vändor, skattad ansträngning samt hjärtfrekvens (HF) registrerades. Utvecklad power (effekt) erhölls genom produkten av vikt, gravitation, antal vändor, höjd på högsta plinten (0,62 m) dividerat med total duration i 5MPT. Testet för att bestämma VO2max utfördes med löpning på ett motordrivet rullband. Under den första minuten av testet sprang tp på en hastighet av 8km/h (kvinnor) respektive10km/h (män) utan lutning. För varje minut ökades hastigheten med 1km/h. Lutningen höjdes med en grad efter minut ett och därefter med 0,5 grader/minut. Testet pågick till dess tp nått sin VO2max. Var 15:e sekund registrerades tp:s HF, VO2 (l/min), VCO2 (l/min), VO2 (ml/kg/min) och respiratorisk kvot (RER) med hjälp av ett datoriserat syreupptagningssystem. Resultat Korrelationen var signifikant och hög (r = 0,89, p&lt;0,0001) mellan utvecklad power på 5MPT och VO2max (l/min) och även mellan antalet vändor på 5MPT och VO2max (l/min) (r = 0,89, p&lt;0,0001) på detta material av elitorienterare. Följande formler, baserade på resultaten från elitorienterarna, kan användas för att predicera VO2max efter genomfört 5MPT: VO2max  (l/min) = (5MPTPOWER – 50,914) / 25,795 VO2max (l/min) = (5MPTVÄNDOR – 74,447) / 9,7668 Slutsats 5MPT uppvisar en stark korrelation med bestämd VO2max sett till power och/eller antalet genomförda vändor. Beräkningsformler för prediktion av VO2max har varit möjligt att beskriva. Se resultatdelen för andra resultat och samband mellan 5MPT och VO2max. / Abstract Aim The aim of this study was to investigate for elite orienteers the results in and the correlation between a so called 5-minutes-pyramid test (5MPT) and a specific maximum oxygen uptake test (VO2max) on a treadmill. The questions we asked ourselves were: Which correlation exists between 5MPT and a specific VO2max on the treadmill for elite orienteers? How would a comparison look like between measured and estimated VO2max? What is the reliability for the 5MPT? How would an equation look like that describe the correlation above? Method In the validity the study 16 elite orienteers (6 women and 10 men) aged 17 to 37 years participated. The two tests that have been carried out were the 5MPT and determined VO2max during running on a treadmill. The 5MPT is a 5-minute-shuttle test, in which the participant moves back and forth in a short interval (5.5 m) over boxes (highest height: 0.62) formed like a pyramid. Power in the pyramid test (5MPTPOWER) was calculated as the product of numbers of laps, body weight, gravity and highest box level divided by time. To determine VO2max the method running on a treadmill was performed. During the first minute the running speed was 8km/h (women)/10 km/h (men) without elevation. Each minute the velocity increased with 1 km/h. The elevation increased with 1 degree after the first minute and thereafter with 0,5 degrees/minute.  The test was finished when the participant had reached her VO2max. Every 15 second the participants heart rate, VO2 (l/min), VCO2 (l/min), VO2 (ml/kg/min) and RER, was registered by means of an online system. Results The correlation between the developed power of the 5MPT and measured VO2max (l/min) was high (r = 0.89, p&lt;0,0001) and also between the number of laps in the 5MPT and measured VO2max (l/min) (r = 0.89, p &lt; 0,0001). The following formulas can be used to predict VO2max after completed 5MPT: VO2max  (l/min) = (5MPTPOWER – 50,914) / 25,795 VO2max (l/min) = (5MPTLAPS – 74,447) / 9,7668 Conclusions 5MPT show a strong correlation with VO2max determined in terms of power and/or the number of completed laps. Calculated formulas for prediction of VO2max have been possible to describe. See results section for other results and relationships between 5MPT and VO2max. / Maximal Aerobic Power versus Performance in Two Aerobic Endurance Tests among Young and Old Adults.Andersson E, Lundahl N, Wecke L, Lindblom I, Nilsson, J.

Background: In the past 37 years, increased efforts have been directed toward a better understanding of the importance of Hcy in disease and it has now become clear that hyperhomocysteinemia is a major independent risk factor for CVD. Extensive research on the influence of vitamin supplementation leading to reductions in Hcy levels and improvements in cardiovascular function has been done. The importance of exercise in the lowering of cardiovascular risk factors, as well as its favourable influence on cardiovascular function has also been indicated in several studies, however, the limited number of studies investigating the effect of exercise on Hcy concentrations revealed contradicting results. Furthermore, a relationship between Hcy concentration and cardiovascular function with the intervention of an exercise training and a vitamin supplementation programme respectively has also not been investigated. Objective: The objective of this study was to examine the effect of a 12-week exercise training and a 12-week vitamin supplementation intervention respectively on tHcy concentrations and cardiovascular function, and whether the change in tHcy concentration within the different interventions correlated with the change in cardiovascular function. Methods: In a randomised controlled cross-over intervention study, 52 men matched for age, cardiorespiratory fitness levels and cardiovascular risk factors were randomly assigned to one of 3 groups (Group A = exercise training programme, 20-30min. at 70-80% of HRmax; Group B = 400 g folic acid and 25 g vitamin B12 supplement; Group C = control). Group A and B were crossed over for phase 11, and Group C remained the control. The questionnaires were completed, and the body composition variables (BMI, WHR and body fat percentage), cardiovascular function (Finometer), tHcy concentrations and VO2max, were measured before and after each 12-week intervention period. A 6-week washout period separated the crossovers. Results: The ANCOVA, adjusted for age and BMI, showed that the percentage change from baseline to end, corrected for baseline of the tHcy concentration increased significantly (p ≤ .05) by 9.7% with the exercise training intervention and decreased significantly (p ≤ .05) by 12.9%, with the vitamin supplementation intervention. The ANCOVA of the percentage change from baseline to end in cardiovascular function showed that the vitamin supplementation intervention resulted in improvements in cardiovascular function (decreased resting MAP, TPR and increased resting SV, CO, Cw) in comparison to the impairment in cardiovascular function with the exercise training intervention (increased resting DBP, MAP and TPR). The relationship between the tHcy concentration and cardiovascular function at baseline and within each of the different interventions were assessed by partial correlations adjusted for age, BMI and VO2max. Significant (p ≤ .05) relationships only occurred within the vitamin supplementation intervention, where decreased percentage change in tHcy concentration significantly correlated with increased percentage change of resting SV and CO and decreased percentage change of resting TPR. Conclusion: The general conclusion that can be drawn is that a 12-week vitamin supplementation intervention showed increased health related results, e.g. a significant reduction in tHcy concentration, an improvement in cardiovascular function and a significant positive relationship between these b o factors, in comparison to the 12-week exercise training intervention that significantly increased the tHcy concentration and did not show increased health related results. Due to inadequate compliance to the exercise training intervention, no conclusion can be drawn with regard to the effect of exercise training on tHcy concentrations and cardiovascular function. / Thesis (M.Sc. (Human Movement Science))--North-West University, Potchefstroom Campus, 2007