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Background: Green tea is rich in catechin, a polyphenolic antioxidant. Consumption of green tea or extract from green tea has been shown to result in weight loss, increased fat oxidation, and elevated energy expenditure in mice and humans. Green tea consumption has also been shown to result in increased exercise endurance in mice and improved maximal oxygen uptake (VO2max) in humans. It is not clearly known whether green tea consumption would increase exercise endurance in humans. Objective: The aim of this study was to determine if the daily consumption of decaffeinated green tea extract for 4-5 weeks, would improve exercise endurance in humans, as measured by running 2.5 miles on an indoor track. Subjects, Design, and Methods: This study was based on a randomized, double-blind design. Fourteen, normal, healthy individuals volunteered for participation and completed the study. They were divided into two groups (n= 7 for each group). All participants completed 2 endurance trials, 1 at the baseline and 1 at the conclusion of the study. Each trial consisted of a 2.5 mile run around the GSU Recreation Center indoor track. One group consumed green tea extract pill containing 900 mg catechins and the other group consumed a placebo for 4-5 weeks between run trials. Results: Green tea and placebo groups improved their running times, however, there was no significant difference between these two groups in mean end time (P = 0.74). Under one statistical analysis, the green tea group significantly improved their running time compared to baseline (P = 0.019), while the placebo group did not. However, under another statistical analysis (removing one participant due to possible skewing effect), both groups significantly improved their running time over baseline (P< 0.05). Conclusions: This study was not able conclusively ascertain whether or not the daily consumption of green tea improved endurance performance as measured by 2.5 mile run times. Results of this study should be used with caution due to small sample size. Future studies are warranted on the impact of green tea consumption on exercise endurance, using a longer duration and a larger sample size than has been studied.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2009. / Härtill 5 uppsatser.

The purpose of this study was to investigate the effects of hydroxytyrosol (HT) supplementation on markers of mitochondrial biogenesis, aerobic capacity, and endurance exercise performance in recreationally active men. Sixty-one (n = 61) subjects (21.46 ± 0.22 yrs, 179.46 ± 0.79 cm, 78.91 ± 1.19 kg) consumed either a high dose (HI) HT supplement (150 mg HT), a low dose (LO) HT supplement (50 mg HT), or a placebo (PLA) every day for 6 weeks. Muscle biopsies from the vastus lateralis were obtained at baseline and after 6 weeks of supplement consumption and analyzed for markers of mitochondrial biogenesis: succinate dehydrogenase (SDH), citrate synthase (CS), and peroxisome proliferator-activated receptor ɣ coactivator (PGC)-1α. Subjects completed exercise testing on a bicycle ergometer at baseline and after 3 and 6 weeks of supplement consumption to measure changes in maximal aerobic power (VO2MAX), lactate threshold, respiratory exchange ratio (RER), substrate utilization, and endurance exercise performance on a 20 km time trial course. The primary findings were that HT supplementation increased muscle oxidative enzyme activity suggesting increased oxidative capacity. HT also increased time trial performance at midpoint and endpoint and this corresponded with an improvement in lactate threshold and a lower RER for the LO HT treatment. Time trial performance was also improved at endpoint for PLA, however, unlike LO an HI HT, this was accompanied by a significant increase in rating of perceived exercise (RPE) and not associated with improvements in muscle oxidative capacity. Our results indicate that HT ranging from 50 to 150 mg/day for 6 weeks can improve muscle oxidative capacity and aerobic performance, and suggests that HT may be used chronically to improve mitochondrial function. HT may be used as an effective means to increase mitochondria to improve exercise performance, and limit diseases associated with mitochondrial dysfunction such as cardiovascular disease, type II diabetes, and some cancers. / text

The purpose of this study was to investigate the effects of 6 weeks of hydroxytyrosol (HT) supplementation on markers of muscle damage in healthy, recreationally active men before and throughout acute aerobic exercise bouts. Using a randomized, double-blind, repeated-measures, placebo-controlled design, sixty-one (n = 61) subjects (21.46 ± 0.22 yrs, 179.46 ± 0.79 cm, 78.91 ± 1.19 kg) consumed either a high dose (HI) HT supplement (150 mg HT), a low dose (LO) HT supplement (50 mg HT), or a placebo (PLA) every day for 6 weeks. Throughout the course of the study, the subjects performed four time trial rides (TT1-TT4) on a cycle ergometer. TT1 occurred before supplementation, TT2 halfway through the supplementation period, and TT3 and TT4 occurred in the sixth week and final two days of supplementation. Blood was drawn prior to (pre) and just before termination (end) of each time trial to measure markers of muscle damage during exercise. We observed that endurance exercise increased indicators of muscle damage, CPK and myoglobin, but an association between HT treatment and reduced muscle damage indicators during exercise were not demonstrated. However, the HT supplementation for 6 weeks in recreationally-active males improved time trial performance in the HT treatment groups over the course of the study and this improvement was accompanied by a lower increase in myoglobin concentration in blood in the HI treatment group than in the LO treatment group. Also, performance was improved after 6 weeks in the PLA group. This improvement was associated with an increase in rating of perceived exertion (RPE). RPE was not increased in either the LO and HI treatment groups, although time trial performance was significantly improved. It is possible that HT can improve performance by altering perception of effort. We conclude that chronic and acute HT supplementation did not reduce markers of muscle damage in this population at rest, during, or following exercise, but improved aerobic performance. / text

The delayed occurrence of fatigue while maintaining submaximal force output is a function that could be driven by the central nervous system (CNS). It has been found previously that mean EMG amplitude increases with fatigue. Endurance time has also been found to increase over repeated testing. The purpose of this study was to compare the muscle activation patterns and endurance times after training of the AdP muscle. This study analyzed surface EMG of the adductor pollicis (AdP) muscle in young, healthy adults during a sustained submaximal isometric fatiguing contraction before and after 4 weeks of muscular endurance task training. Eight participants (training group: n = 4 and control group: n = 4) carried out maximal voluntary contractions (MVCs) while sustaining isometric force of 20% MVC of thumb adduction before and after the four weeks of endurance training. EMG, recorded through surface electrodes, was measured before and after training in an effort to detect a possible CNS training effect. The endurance training group trained the AdP muscle at 20% MVC every other day for 4 weeks. Average force was calculated over 5 second time bins every 5% of endurance time (20 time bins total). A significant increase in endurance time was seen in the training group of this study. A significant effect of change for pre and post-training mean EMG amplitude across the two groups was found (p < .001). A significant interaction effect between pre and post training and control groups was also found (p = .016). There was also a significant deficit in increases of mean amplitude between the first and last time bins of the endurance task (pre and post) after training. This indicates that there is an effect of training on increasing endurance time which can be exhibited through changes in mean EMG amplitude. / text

SUMMARY The endurance and mobility of spinal muscles in 6-7 year old children The problem of the study: The health of a child depends not only on genetic factors, conditions of life, and nutrition but also on the health education in family, kindergarten and school, on the conditions of hygiene and lifestyle. The training of the posture occupies an important place in contemporary system of health education of preschool and junior school age children. The beginning of posture disorders has to be looked for not in schools. Optimal muscle activity determines the correctness of the posture. The correct posture is formed with the well-timed and adequate assessment of the condition of the muscles, determination of the muscles’ weakness or the reduction of endurance, and adequate training. The aim of the work: To assess the endurance and mobility of spinal muscles in 6-7 year old children. The objectives: 1. To assess the endurance of spinal, abdominal and lateral muscles in 6-7 year old children. 2. To assess the mobility of lateral waist muscles in 6-7 year old children. 3. To assess the endurance of abdominal, spinal, and lateral muscles and the lateral mobility of the spine in boys and girls. 4. To determine the correlative relationship between the endurance of spinal, abdominal and lateral waist muscles and the mobility of the waist. The hypothesis: We claim that the endurance of the flexion of the waist to the left and right sides and the endurance of abdominal... [to full text]

Introduction : L'obésité est devenue une problématique prédominante dans notre société actuelle. Effectivement, en 2005, l'organisation mondiale de la santé estimait à plus de 400 millions le nombre d'individus obèses et elle estime qu'en 2015, 700 millions d'individus seront obèses. De plus, durant le processus du vieillissement et plus spécifiquement lors de la ménopause, on assiste à une modification de la composition corporelle (gain de masse grasse et perte de masse musculaire). Récemment, un sous-type d'obèse sain (MHO: Metabolically Healthy but Obese) a été mis en évidence dans la littérature. Contrairement aux obèses à risque, les MHO présentent des composantes métaboliques saines (e.g. profil insulinémique, lipidique et inflammatoire) malgré la présence excessive de masse grasse. Les interventions visant la perte de masse grasse semblent avoir des effets différents chez ces deux sous-types d'obèses. Effectivement, une diminution de la sensibilité à l'insuline a été observée chez les obèses MHO suite à une restriction calorique de 6 mois contrairement à l'amélioration observée chez les obèses à risque. Ainsi, il est primordial d'identifier une intervention qui permettra une amélioration de la composition corporelle chez les obèses MHO tout en conservant leur profil métabolique favorable. Il a été montré que l'entraînement en résistance permettait d'améliorer la composition corporelle, le contrôle de la glycémie, la masse grasse abdominale et la tension artérielle. Objectif : Ainsi, l'objectif de cette étude était de : 1) Comparer l'effet d'un entraînement en résistance de 16 semaines sur la masse grasse chez des femmes post-ménopausées obèses à risque et MHO. 2) Vérifier et comparer si ce type d'intervention à un effet sur les composantes du profil métabolique (tour de taille, glycémie, tension artérielle, triglycérides, HDL) chez des femmes post-ménopausées obèses à risque et MHO. Méthodes : Trente-six femmes post-ménopausées, obèses, sédentaires ont été recrutées. Les MHO ont été identifiés selon les critères du syndrome métabolique définis par la Fédération International de Diabète (circonférence de taille > 88 cm et 2 des 4 facteurs suivants : triglycérides > 1,7 mmol/L; HDL < 1,3 mmol/L; tension artérielle systolique > 130 mmHg ou diastolique > 85 mmHg ; glycémie à jeun > 5,6 mmol/L). À partir de cette méthode, les participantes ayant le syndrome métabolique ont été classées dans la catégorie des obèses à risque, les autres ont été classées dans la catégorie des obèses MHO. Le profil métabolique (tension artérielle, glycémie à jeun, insuline à jeun, triglycérides et cholestérol total), la composition corporelle (tour de taille, masse grasse et masse maigre) et la force musculaire (test de 1 répétition maximale (RM) au développé des jambes et développé des bras) ont été mesurés avant et après intervention. Les participantes ont suivi un programme d'entraînement en résistance supervisé d'une durée de 16 semaines (1h/3x/semaine). Résultats : Suite à l'intervention, une diminution significative de la masse grasse totale (%) ainsi qu'une augmentation significative de la masse maigre totale (kg), du 1RM au développé des jambes et du 1RM au développé des bras ont été observées chez les deux groupes. Finalement, aucune différence significative n'a été observée pour les composantes métaboliques. Conclusion : Un entraînement en résistance d'une durée de quatre mois entraine une diminution de la masse grasse totale (%), une augmentation de la masse musculaire totale (kg) et une augmentation de la force sans avoir d'effets sur les composantes métaboliques (tension artérielle, glucose à jeun, insuline à jeun, ApoB, triglycérides, cholestérol total, HDL-cholestérol, LDL-cholestérol et CRP) autant chez les femmes post-ménopausées obèses à risque que chez celles MHO. Ainsi, l'entraînement en résistance est donc à recommander chez la femme post-ménopausée obèse à risque et MHO. ______________________________________________________________________________

Tyrimo tikslas – išsiaiškinti kaip greitumo ir ištvermės fizinis krūvis veikia regbio žaidėjų fizinių gebėjimų rodiklius. Hipotezės – keliame prielaidas, kad -trijų savaičių greitumo fizinis krūvis, teigiamai įtakos regbio žaidėjų greitumo bei galingumo rodiklius ir turės neigiamos įtakos maksimalios jėgos rodikliams. -trijų savaičių ištvermės fizinis krūvis turės neigiamos įtakos greitumo, galingumo ir maksimalios jėgos rodikliams. Tyrimo uždaviniai: 1. Ištirti kaip trijų savaičių greitumo fizinis krūvis veikia regbio žaidėjų maksimalios jėgos (pritūpimas su štanga), galingumo (30 metrų bėgimas iš starto), bei greitumo (30 metrų bėgimas įsibegėjus) rodiklius. 2. Nustatyti kaip trijų savaičių ištvermės fizinis krūvis veikia regbio žaidėjų maksimalios jėgos (pritūpimas su štanga), galingumo (30 metrų bėgimas iš starto), bei greitumo (30 metrų bėgimas įsibegėjus) rodiklius. Rezultatai.Tyrimo rezultatai parodė, kad po trijų savaičių greitumo fizinio krūvio, greitumo ir galingumo rezultatai turėjo tendenciją gerėti: galingumo rezultatai prieš krūvį 3,72 ± 0,27 s, po krūvio 3,65 ± 0,21 s, greitumo rezultatai prieš krūvį 4,22 ± 0,26 s, po krūvio 4,17 ± 0,24 s, tačiau statistiškai reikšmingo skirtumo nebuvo rasta (p > 0,05). Maksimalios jėgos rezultatai statistiškai reikšmingai pablogėjo (p > 0,05), prieš krūvį 101,82 ± 12,70 kg, po krūvio 95,00 ± 5,48 kg.Tyrimo rezultatai gauti po trijų savaičių ištvermės fizinio krūvio parodė, kad galingumo testo rezultatai turėjo tendenciją... [toliau žr. visą tekstą] / Purpose: the aim of this study is to investigate how speed and endurance training will affect the physical abilities in rugby players. Hypotheses - we presume that -three weeks of speed training will have positive effect on power and speed indicators and may affect negatively maximum strength indicators in rugby players. -three weeks of endurance training for rugby players, will affect all three previously mentioned physical indicators negatively. The objectives of the research: 1. Determine how three weeks of speed training will affect the following factors in rugby players: maximal strength (1RM squat with „Smith machine“), power (30 metres dash), speed (30 metres dash with flying start). 2. Investigate how three weeks of endurance training will affect the following factors in rugby players: maximal strength (1RM squat with „Smith machine“), power (30 metres dash), speed (30 metres dash with flying start). Results. Results of the first research demonstrated that three weeks of speed training had tendency to positively influence: speed from 3,72 ± 0,27 s, to 3,65 ± 0,21 s and also power from 4,22 ± 0,26 s, to 4,17 ± 0,24 s, but no significant changes were found (p > 0,05). Maximum strength indicators significantly (p < 0,05) decreased after three weeks speed training programme, from 101,82 ± 12,70 kg, to 95,00 ± 5,48 kg. Results of our second research demonstrated that three weeks of endurance training had tendency to negatively influence power: from 4,16 ± 0,24 s, to 4,25... [to full text]

Pagrindinis širdies ir kraujagyslių sistemos uždavinys – deguonies ir maisto medžiagų tiekimas. Deguonimi ir maisto medžiagomis kraujas aprūpina dirbančius raumenis ir kitus organus. Darbo tikslas – palyginti ištvermę lavinančių sportininkų ir nesportuojančiųjų širdies funkcinį parengtumo ypatybes taikant elektrokardiografijos metodą ir skirtingo kryptingumo fizinio krūvio mėginius. Uždaviniai: 1 - palyginti nesportuojančiųjų ir ištvermę lavinančių sportininkų ŠSD kaitos ypatybes atliekant pakopomis didėjantį krūvį veloergometru; 2 - palyginti nesportuojančiųjų ir ištvermę lavinančių sportininkų ŠSD kaitos ypatybes atliekant dozuoto krūvio mėginį; 3 - palyginti nesportuojančiųjų ir ištvermę lavinančių sportininkų ŠSD kaitos ypatybes atliekant maksimalaus anaerobinio krūvio mėginį; 4 – palyginti trijų skirtingų fizinio krūvio mėginių informacinės dimensijos reikšmes, kai elektrokardiografijos metodu vertinama funkcinio parengtumo ypatybės. Metodika. Buvo tirta 7 ištvermės rungčių atstovai lengvaatlečiai ir 16 nesportuojančių asmenų. Tiriamieji atliko tris fizinio krūvio mėginius: pakopomis didėjantį krūvį veloergometru; Rufje fizinio krūvio mėginį ir 30 - s vertikalaus šuoliavimo testą. Kompiuterine EKG registravimo ir analizės sistema „Kaunas-krūvis“ buvo registruojama EKG ir vertinama ŠŠD, JT intervalo, ST-segmento depresijos kaita atliekant krūvius ir pirmąsias tris atsigavimo minutes. Rezultatai ir išvados. Pakopomis didėjančio krūvio metu registruojant... [toliau žr. visą tekstą] / Cardiovascular system is the main physiological system determining physical working capasity or endurance. The main task of cardiovascular system to deliver the oxygen anf energy substrates to tisues and muscles as well. The purpors of this study was to compare functional peculiarities of cardiovascular system in endurance and non-sportsmans cohorts while performing various exercise tests. Objectives: 1 - to compare the cardiovascular reactions in endurance and non-sportsmans cohorts while performing graded exercise stress (bycycle ergometry); 2 – to compare the cardiovascular reactions in endurance and non-sportsmans cohorts while performing dosed aerobic exercise test; 3 – to compare the cardiovascular reactions in endurance and non-sportsmans cohorts while performing maximal anaerobic workload (30-s vertical jumps test); 4 – to compare the informativeness of aplyed exercise protocols for assessment of cardiovascular reactions in endurance and non-sportsmans cohorts. Methods. The participant fo this study was 7 endurance athletes and 16 non-sportsman. Subjects performed three exercise tests: graded exercise stress (bycycle ergometry); dosed aerobic exercise test (Roufier Test) maximal anaerobic workload (30-s vertical jumps test). A computerized ECG analysis system "Kaunas-load" was recorded ECG and assessed FCU, JT interval, ST-segment depression changes in workloads and the first three minutes of recovery. Results and Conclusions. The registration of ECG during the... [to full text]