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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

HUMAN BLOOD LACTATE AND AMMONIA LEVELS AFTER SUPRAMAXIMAL UPHILL AND DOWNHILL RUNNING

MIYAMURA, MIHARU, YAMAZAKI, YOSHIHIKO, OHKUWA, TETSUO, ITOH, HIROSHI 27 December 1996 (has links)
No description available.
2

The effects of different intermittent priming strategies on 3km cycling performance

McIntyre, Jordan Patrick Ross January 2007 (has links)
Priming exercise, or the ‘warm-up’, is an accepted practice prior to exercise participation, physical training or sporting competition. Traditionally, low intensity exercise has been used prior to both short- and long-duration events in an effort to prepare the athlete, but not fatigue them. Recently, however, a more scientific approach to priming exercise has been considered important, with some research suggesting that a high intensity intermittent priming strategy may be optimal. However, given the paucity of performance focussed ‘warm-up’ studies, and that existing data regarding high-intensity priming strategies is inconclusive, the aim of this thesis was to determine the effects of three high-intensity intermittent priming strategies on physiological responses and subsequent 3km laboratory time-trial (TT) performance. Ten well-conditioned endurance-trained male cyclists (mean ± SD: age, 28.3 ± 8.4 yr, body mass, 81.8 ± 11.6 kg, stature, 1.8 ± 0.1 m, O2peak, 4.6 ± 0.5 L•min−1) were recruited for this study. After an initial incremental exercise test to exhaustion, participants completed four 3km time trials (TT) on four separate occasions, each preceded by a different priming strategy. These included a ‘self-selected’ (control) condition, and three high-intensity intermittent priming strategies of varying intensity (100% and 150% of the power at O2peak, and all-out) and fixed duration (15 minutes), each in predetermined random order. Five minutes passive rest separated each priming exercise condition from the experimental 3km-TT. Oxygen uptake ( O2) and heart rate (HR) were measured continuously, while blood lactate concentration ([BLa]) and core temperature (TC) were recorded at rest, post-priming exercise, and immediately prior to and following the 3km-TT. In an attempt to provide a mechanistic explanation for changes in performance, O2 kinetic variables were determined from the O2 data. Performance was quantified as a mean power (Wmean) and total time taken to complete the 3km-TT. Mean power output and time taken for each 500m segment of the 3km-TT were also calculated. Results demonstrated that the athletes self-chosen priming condition (378.6 ± 44.0 W) resulted in Wmean that was slightly greater than both the lowest (376.3 ± 44.9 W; 0.7%; p = 0.57) and moderate (373.9 ± 47.8 W; 1.5%, p = 0.30) intensity intermittent priming condition, but significantly greater than the ‘all-out’ intermittent sprint priming condition (357.4 ± 44.5 W; 5.8%, p = 0.0033). Similar differences were observed for time. While differences existed in the O2 deficit (however, mainly non-significant), these differences did not provide clear explanations for the differences in performance, with the moderate priming condition displaying a significantly reduced O2 deficit (59.4 ± 15.6 L, p < 0.05), despite the non-significant change in Wmean, compared to the self-chosen priming condition (73.3 ± 18.6 L). Additionally no significant differences were observed in either the time constant or the mean response time of O2. Significant findings with regard to HR, [BLa] and TC were observed, but consistent with O2 kinetic variables, they were not related to, nor explain performance changes. In conclusion, regardless of intensity, different high-intensity intermittent priming exercise did not improve 3km-TT performance more than the control condition (self-chosen). A priming strategy that is overly intense was detrimental to subsequent cycling performance. The observed finding that a self-chosen priming strategy resulted in a comparable performance suggests that athletes are able to self-select (consciously or sub-consciously) a ‘warm-up’ that is of appropriate intensity/duration. Further work utilising the priming strategies from the current study with events of shorter duration is required to further clarify how priming strategies of this nature may affect track cycling performance.
3

Metabolic Responses to Supramaximal Exercise and Training: A Gender Comparison

Weber, Clare L., n/a January 2003 (has links)
The primary aim of this thesis was to investigate the gender-specific responses to supramaximal cycling and to examine the changes in anaerobic and aerobic metabolism that occur in response to high-intensity interval training (HIT). All subjects in the present experiments were untrained, healthy young adults aged between 18 and 35 yr. Cycle ergometry was used for all experimental test procedures and training programs. The accumulated oxygen (AO2) deficit was used to quantify the production of adenosine triphosphate (ATP) via anaerobic metabolism during supramaximal cycling. In addition, pulmonary oxygen uptake measured at the onset of exercise was described using mathematical modeling to determine the rate response of the aerobic energy system during exercise. The purpose of experiment one was to examine the test-retest reliability of the maximal accumulated oxygen deficit (MAOD) measured at 110% and 120% of peak oxygen uptake for cycling in seven untrained male and seven untrained female subjects. After one familiarization trial, all subjects performed two MAOD tests at a power output corresponding to 110% and two tests at 120% of peak oxygen uptake in random order. MAOD was calculated for each subject as the difference between the estimated AO2 demand and the AO2 uptake measured during the exercise bout. The mean±standard error time to exhaustion (TE) for the group was not significantly different between trial one (226±13 s) and trial two (223±14 s) of the 110% test. Likewise, the difference in the TE between trial one (158±11 s) and trial two (159±10 s) was not significant for the 120% test. The intra-class correlation coefficients for the TE were 0.95 for the 110% test and 0.98 for the 120% test. The mean MAOD value obtained in trial one (2.62±0.17 L) was not significantly different from the mean value obtained in trial two (2.54±0.19 L) for the 110% test. Additionally, the mean values for the two trials did not differ significantly for MAOD (2.64±0.21 L for trial one and 2.63±0.19 L for trial two) in the 120% test. The intra-class correlation coefficients for MAOD were 0.95 for the 110% test and 0.97 for the 120% test. All intra-class correlation coefficients were significant at p < 0.001. When conducted under standardized conditions, the determination of MAOD for cycling was highly repeatable at both 110% and 120% of peak oxygen uptake in untrained male and female subjects. The results observed in experiment one suggest that the MAOD may be used to compare the anaerobic capacity (AC) of men and women and to examine changes in the contribution of the anaerobic energy systems before and after training. Experiment two examined the gender-specific differences in MAOD before and after 4 and 8 wk of HIT. Untrained men (n=7) and women (n=7) cycled at 120% of pre-training peak oxygen uptake to exhaustion (MAOD test) pre-, mid-, and post-training. A post-training timed test was also completed at the MAOD test power output, but this test was stopped at the TE achieved during the pre-training MAOD test. The 14.3±5.2% increase in MAOD observed in males after 4 wk of training was not different from the 14.0±3.0% increase seen in females (p > 0.05). MAOD increased by a further 6.6±1.9% in males and this change was not different from the additional 5.1±2.3% increase observed in females after the final 4 wk of training. Peak oxygen uptake measured during incremental cycling increased significantly (p < 0.01) in male but not in female subjects after 8 wk of training. Moreover, the AO2 uptake was higher in men during the post-training timed test compared to the pre-training MAOD test (p < 0.01). In contrast, the AO2 uptake was unchanged from pre- to post-training in female subjects. The increase in MAOD with training was not different between men and women suggesting an enhanced ability to produce ATP anaerobically in both groups. However, the increase in peak oxygen uptake and AO2 uptake obtained in male subjects following training indicates improved oxidative metabolism in men but not in women. It was concluded that there are basic gender differences that may predispose males and females to specific metabolic adaptations following an 8-wk period of HIT. Increases in AO2 uptake during supramaximal cycling demonstrated in men after training led to the hypothesis that peak oxygen uptake kinetics are speeded in male subjects with short-term HIT. It was suggested that training does not improve peak oxygen uptake kinetics in women as no change in AO2 uptake was found after 8 wk of HIT in female subjects. The purpose of experiment three was to examine peak oxygen uptake kinetics before and after 8 wk of HIT in six men and six women during cycling at 50% (50% test) and 110% (110% test) of pre-training peak oxygen uptake. A single-term exponential equation was used to model the peak oxygen uptake response (after phase I) during the 50% and 110% tests pre- and post-training. In addition, phase II and III of the peak oxygen uptake response during the 110% tests were examined using a two-term equation. The end of the phase I peak oxygen uptake response was identified visually and omitted from the modeling process. The duration of phase I determined during all experimental tests was not different between men and women and did not change with training in either group. Before training, men obtained a phase II peak oxygen uptake time constant (t2) of 29.0±3.3 s during the 50% test which was not different to the t2 of 28.8±2.2 s attained by women. In addition, the t2 determined during the 50% test was unchanged after 8 wk of HIT in both groups. The peak oxygen uptake kinetics examined during the 110% tests before training were well described by a single-term model in all male and female subjects. The t2 determined before training for the 110% test was significantly faster in men than in women. Furthermore, peak oxygen uptake was unchanged in female subjects and the t2 remained unaltered with 8 wk HIT (pre 45.5±2.2; post 44.8±2.3 s). In contrast, male subjects achieved a significantly higher peak oxygen uptake after training and the t2 determined for men during the 110% test was faster after training (36.4±1.6 s) than before training (40.1± 1.9 s). Improved model fits were obtained with the two-term equation compared to the single-term equation in two of the six male subjects during the 110% test post-training. It was found that the onset of the peak oxygen uptake slow component occurred at a mean time of 63.5±2.5 s and the t2 was reduced to 18.4±1.7 s. Using a Wilcoxon Signed Ranks z-test, the t2 described by the single-term equation in the remaining four subjects was determined to be significantly faster after training than before training, thus confirming the results obtained from the original group (n=6) of male subjects. End exercise heart rate (HREE) values obtained during the 50% and 110% tests were not different between men and women. During the 50% test, HREE values were unchanged, whereas HREE was significantly decreased during the 110% test after training in both groups. These data show that HIT might improve oxidative metabolism in men but not in women as reflected by a greater peak oxygen uptake and faster peak oxygen uptake kinetics during supramaximal work rates. We further suggest that the faster peak oxygen uptake kinetics demonstrated in men after training are probably not due to an improvement in cardiac function. Finally, the augmentation of oxidative metabolism during exercise after HIT in men might be dependent on the intensity of the exercise bout at which the peak oxygen uptake response is examined. The findings presented in this thesis suggest that MAOD is a reliable measure in both male and female subjects and can be used to monitor changes in anaerobic ATP production during supramaximal cycling. Moreover, these data suggest that 4 and 8 wk of HIT produce similar changes in anaerobic ATP generation in men and women. Finally, 8 wk of HIT results in the increase of peak oxygen uptake and AO2 uptake as well as the speeding of peak oxygen uptake kinetics during supramaximal cycling in male subjects. There was no evidence to suggest that oxidative metabolism was improved in women after short-term HIT. In conclusion, improvement in supramaximal exercise performances should be examined specifically for changes in the anaerobic and aerobic contributions to energy production. In addition, it is suggested that gender should be of primary consideration when designing exercise-training programs where improvement in both anaerobic and aerobic metabolism is required.
4

The effects of different intermittent priming strategies on 3km cycling performance

McIntyre, Jordan Patrick Ross January 2007 (has links)
Priming exercise, or the ‘warm-up’, is an accepted practice prior to exercise participation, physical training or sporting competition. Traditionally, low intensity exercise has been used prior to both short- and long-duration events in an effort to prepare the athlete, but not fatigue them. Recently, however, a more scientific approach to priming exercise has been considered important, with some research suggesting that a high intensity intermittent priming strategy may be optimal. However, given the paucity of performance focussed ‘warm-up’ studies, and that existing data regarding high-intensity priming strategies is inconclusive, the aim of this thesis was to determine the effects of three high-intensity intermittent priming strategies on physiological responses and subsequent 3km laboratory time-trial (TT) performance. Ten well-conditioned endurance-trained male cyclists (mean ± SD: age, 28.3 ± 8.4 yr, body mass, 81.8 ± 11.6 kg, stature, 1.8 ± 0.1 m, O2peak, 4.6 ± 0.5 L•min−1) were recruited for this study. After an initial incremental exercise test to exhaustion, participants completed four 3km time trials (TT) on four separate occasions, each preceded by a different priming strategy. These included a ‘self-selected’ (control) condition, and three high-intensity intermittent priming strategies of varying intensity (100% and 150% of the power at O2peak, and all-out) and fixed duration (15 minutes), each in predetermined random order. Five minutes passive rest separated each priming exercise condition from the experimental 3km-TT. Oxygen uptake ( O2) and heart rate (HR) were measured continuously, while blood lactate concentration ([BLa]) and core temperature (TC) were recorded at rest, post-priming exercise, and immediately prior to and following the 3km-TT. In an attempt to provide a mechanistic explanation for changes in performance, O2 kinetic variables were determined from the O2 data. Performance was quantified as a mean power (Wmean) and total time taken to complete the 3km-TT. Mean power output and time taken for each 500m segment of the 3km-TT were also calculated. Results demonstrated that the athletes self-chosen priming condition (378.6 ± 44.0 W) resulted in Wmean that was slightly greater than both the lowest (376.3 ± 44.9 W; 0.7%; p = 0.57) and moderate (373.9 ± 47.8 W; 1.5%, p = 0.30) intensity intermittent priming condition, but significantly greater than the ‘all-out’ intermittent sprint priming condition (357.4 ± 44.5 W; 5.8%, p = 0.0033). Similar differences were observed for time. While differences existed in the O2 deficit (however, mainly non-significant), these differences did not provide clear explanations for the differences in performance, with the moderate priming condition displaying a significantly reduced O2 deficit (59.4 ± 15.6 L, p < 0.05), despite the non-significant change in Wmean, compared to the self-chosen priming condition (73.3 ± 18.6 L). Additionally no significant differences were observed in either the time constant or the mean response time of O2. Significant findings with regard to HR, [BLa] and TC were observed, but consistent with O2 kinetic variables, they were not related to, nor explain performance changes. In conclusion, regardless of intensity, different high-intensity intermittent priming exercise did not improve 3km-TT performance more than the control condition (self-chosen). A priming strategy that is overly intense was detrimental to subsequent cycling performance. The observed finding that a self-chosen priming strategy resulted in a comparable performance suggests that athletes are able to self-select (consciously or sub-consciously) a ‘warm-up’ that is of appropriate intensity/duration. Further work utilising the priming strategies from the current study with events of shorter duration is required to further clarify how priming strategies of this nature may affect track cycling performance.
5

EFFECTS OF A PROPER COOL-DOWN AFTER SUPRAMAXIMAL INTERVAL EXERCISE ON PULSE WAVE REFLECTION, AORTIC STIFFNESS, AND AUTONOMIC MODULATION

Parks, Jason C. 15 May 2020 (has links)
No description available.
6

Approche intégrée et moléculaire du métabolisme anaérobie chez le rameur entrainé

Maciejewski, Hugo 28 April 2009 (has links) (PDF)
Ce travail avait pour objectif i) d'analyser les caractéristiques physiologiques et musculaires(déterminées d'après des biopsies) de rameurs poids légers entraînés, ii) de proposer une méthode de153calcul pour estimer de façon non-invasive la quantité de lactate accumulé dans l'organisme (QTLS) au cours d'un exercice épuisant sur ergomètre aviron d'après la modélisation de la cinétique lactique pendant la récupération et iii) d'explorer l'influence des caractéristiques musculaires, et de l'aptitude à échanger et à éliminer le lactate sur la capacité anaérobie des rameurs appréciée par la mesure du déficit maximal d'O2 cumulé (DMOC).Premièrement, les rameurs étudiés possédaient un rapport masse musculaire - masse corporelle élevé et leurs paramètres physiologiques et musculaires étaient caractéristiques des athlètes spécialisées en endurance.Dans un deuxième temps, nous avons démontré que QTLS était corrélé positivement à DMOC.Cette relation supporte notre hypothèse et confirme la cohérence de la méthode proposée pour calculer QTLS.Dans une dernière étude, les résultats ont démontré que DMOC était corrélée positivement à l'aptitude à éliminer le lactate. Cette dernière était également significativement corrélée à la densité capillaire et au contenu musculaire en MCT4, une protéine impliquée dans le cotransport lactate-proton à travers le sarcolemme.
7

Concentração Alveolar Mínima do Isofluorano em catetos (Tayassu tajacu, LINNAEUS, 1758) / Maria Gláucia Carlos. Isoflurane minimum alveolar concentration in collared peccary (Tayassu tajacu)

Oliveira, Maria Gláucia Carlos de 08 August 2013 (has links)
Made available in DSpace on 2016-08-15T20:31:30Z (GMT). No. of bitstreams: 1 MariaGCO_DISSERT.pdf: 3651986 bytes, checksum: 2ab08d5fd194352621c2b0fa211f2e22 (MD5) Previous issue date: 2013-08-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Inhalation anesthesia has been widespread in veterinary medicine. Nevertheless, its use in wild animals is still limited, having no studies on its use been observed in the species. The objective of the research was to determine the isoflurane minimum alveolar concentration (MAC) in peccaries and present the effects of its administration on the hemodynamic and respiratory variables, as well as data concerning the anesthesia recovery. The study used 10 male animals with age ranging from 1 to 3 years, from the Centro de Multiplicação de Animais Silvestres of Universidade Federal Rural do SemiÁrido, Brazil. All the animals had anesthesia induced with propofol 7mg.kg-1, were intubated and connected to the anesthetic circuit with isoflurane and 100% oxygen. The supramaximal noxious stimulation used was the interdigital pinch, which was performed after 15 minutes of waiting for each provided isoflurane concentration. When negative response to the stimulus was observed, the concentration was reduced by 20%; when positive response was verified, the stimulus was stopped, being the CAM value calculated from that point. Quantitative and qualitative data regarding recovery were also observed. Shapiro-Wilk test for normality was performed, as well as Levene test for equality of variance; the variables were subjected to One Way RM ANOVA for repeated measures followed by Tukey test, and the data expressed as mean and standard deviation. The MAC of isoflurane was 2.4% and the surgical MAC equal to 3.5%. Depressive action of isoflurane on blood pressure, heart and breathing rates was observed when compared to the average of the variables on awake animals; however, during maintenance of anesthesia, they remained stable. Metabolic acidosis was observed in the preanesthetic, which was offset after inhalation anesthesia. Recovery was quiet and smooth. It was concluded that the isoflurane MAC for peccaries was greater than that observed in related species. Isoflurane can be used in this species, being considered safe and effective. The animal s recovery after anesthesia with isoflurane was free from excitement / A anestesia inalatória vem sendo amplamente difundida na medicina veterinária, no entanto seu uso em animais selvagens ainda é restrito, não sendo observado nenhum estudo referente à sua utilização na espécie Tayassu tajacu. O objetivo da pesquisa foi determinar a concentração alveolar mínima (CAM) do isofluorano em catetos e apresentar os efeitos desta administração sobre as variáveis hemodinâmicas e respiratórias, como também a qualidade da recuperação. Utilizou-se 10 animais, machos, com idade variando de 1 a 3 anos oriundos do Centro de Multiplicação de Animais Silvestres da Universidade Federal Rural do Semi-Árido, Brasil. Todos tiveram anestesia induzida com 7 mg.kg-1 de propofol e posteriormente foram conectados a circuito anestésico com isofluorano e oxigênio 100%. O estímulo noceptivo supramáximo adotado foi pinçamento interdigital, o qual era realizado após 15 minutos de espera para cada concentração de isofluorano fornecida. Ao ser observada resposta negativa frente ao estímulo a concentração era reduzida em 20%, quando verificada resposta positiva o estímulo era cessado, calculando-se a partir daí o valor da CAM. Observou-se dados quantitativos e qualitativos referentes à recuperação. Utilizou-se o teste de normalidade de Shapiro Wilk e de homogeneidade de variânica de Levene, as variáveis avaliadas foram submetidas à One Way ANOVA-RM para medidas repetidas, seguidas por Teste Tukey, sendo os dados expressos em média e desvio padrão. A CAM do isofluorano foi de 2,4%, sendo a CAM cirúrgica igual a 3,5%. Observou-se ação depressiva do isofluorano sobre a pressão arterial, frequência cardíaca e respiratória quando comparada a média dessas variáveis para animais acordados, entretanto durante a manutenção anestésica mantiveram-se estáveis. Observou-se acidose metabólica no período pré-anestésico o qual foi compensado após a realização da anestesia inalatória. A recuperação anestésica foi tranquila e rápida. Concluiu-se que a CAM do isofluorano para catetos foi maior que a observada em espécies afins. O isofluorano pode ser utilizado nesta espécie, sendo considerado seguro e eficaz. A recuperação dos animais após anestesia com isofluorano foi livre de excitação
8

Approche intégrée et moléculaire du métabolisme anaérobie chez le rameur entrainé / Integrated and molecular approach of anaerobic metabolism in trained oarsmen

Maciejewski, Hugo 28 April 2009 (has links)
Ce travail avait pour objectif i) d’analyser les caractéristiques physiologiques et musculaires(déterminées d’après des biopsies) de rameurs poids légers entraînés, ii) de proposer une méthode de153calcul pour estimer de façon non-invasive la quantité de lactate accumulé dans l’organisme (QTLS) au cours d’un exercice épuisant sur ergomètre aviron d’après la modélisation de la cinétique lactique pendant la récupération et iii) d’explorer l’influence des caractéristiques musculaires, et de l’aptitude à échanger et à éliminer le lactate sur la capacité anaérobie des rameurs appréciée par la mesure du déficit maximal d’O2 cumulé (DMOC).Premièrement, les rameurs étudiés possédaient un rapport masse musculaire - masse corporelle élevé et leurs paramètres physiologiques et musculaires étaient caractéristiques des athlètes spécialisées en endurance.Dans un deuxième temps, nous avons démontré que QTLS était corrélé positivement à DMOC.Cette relation supporte notre hypothèse et confirme la cohérence de la méthode proposée pour calculer QTLS.Dans une dernière étude, les résultats ont démontré que DMOC était corrélée positivement à l’aptitude à éliminer le lactate. Cette dernière était également significativement corrélée à la densité capillaire et au contenu musculaire en MCT4, une protéine impliquée dans le cotransport lactate-proton à travers le sarcolemme. / The aim of this work was i) to analyse physiological and muscle characteristics (determinedfrom muscle biopsies) in trained lightweight oarsmen, ii) to propose a non-invasive method to estimatelactate accumulation in the organism (QTLS) using the blood lactate recovery kinetics in response to anall-out exercise on rowing ergometer and iii) to explore the influence of muscle characteristics andlactate exchange and removal abilities on the anaerobic capacity of our subjects determined from themeasurement of the maximal accumulated oxygen deficit (MAOD).Firstly, the studied oarsmen displayed an elevated muscle - body mass ratio and their muscleand physiological characteristics were typical of those of elite endurance athletes.Secondly, we showed that QTLS was positively correlated with MAOD. This relationshipsupports our hypothesis and reinforces the interest of our method to estimate QTLS.Finally, the results demonstrated that MAOD was positively correlated with the lactate removalability. This latter was also positively correlated with the capillary density and the muscle content ofMCT4, a protein involved in the cotransport of lactate and proton across the sarcolemma
9

Suplementação com bicarbonato de sódio: influência sobre o desempenho, respostas fisiológicas e neuromusculares durante e após exercício supramáximo no ciclismo / Sodium bicarbonate supplementation: effect on physiological and neuromuscular performance during and after supramaximal exercises in cycling

Schlickmann, Jardel 23 April 2012 (has links)
Made available in DSpace on 2016-12-06T17:06:50Z (GMT). No. of bitstreams: 1 Jardel Schlickmann.pdf: 828069 bytes, checksum: 28142f1471dd5fe8cbc06d71583812dd (MD5) Previous issue date: 2012-04-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The purpose of this study was to determine whether supplementation with sodium bicarbonate (NaHCO3) changes in performance during supramaximal cycling exercise (ESupra), the cardiorespiratory variables and subsequent isometric muscle strength (IMS). The study include 8 male subjects, physically active (23,0±4,01years; 54,69±6,51ml/kg/min-1). The subjects underwent an all out ESupra at 1min in cycle ergometer with load 0,075 kg/weight, after ingestion of solution 0,3g/kg with NaHCO3 or placebo (PLAC) with 0,045g/kg NaCl. After performed the IMS for the upper and lower limbs. The NaHCO3 did not affect the ESupra (497,45±52,47W) compared with PLAC (497,97±60,15W). There were no effects of the ESupra or NaHCO3 ingestion of the test IMS for the elbow flexors (NaHCO3 pre 38,4±6,6kgf and post 36,7±7,8kgf; PLAC pre 37,1±6,8kgf and post 36,2±8,0kgf), as well as for IMS the knee extensors (NaHCO3 pre 84,68±12,36kgf and after 80,28±11,88kgf; PLAC pre 87,04±16,38kgf and after 81,20±13,41kgf). In relation the physiological responses was observed a significant increase at the end of the ESupra only to VCO2 (4,93±0,47l/min) in the condition NaHCO3 compared to PLAC (4,44±0,28l/min). No differences were observed for VO2, VE and VCO2 at anytime during recovery. Lactate concentrations were differently to blood condition NaHCO3 compared to PLAC from the second minute after the ESupra. Before these results, it is likely that the increase in blood lactate concentration after ingestions of NaHCO3 was due to increased release of lactate exercised by muscle and/or by decreasing the absorption in other tissues, since not presented evidence of increased production during exercise (i.e. improved performance). Moreover, the largest peak value during the VCO2 in ESupra suggest a lager buffering H+ generated by supplementation with NaHCO3. Despite evidence to demonstrate the action of NaHCO3 on acid-base balance and transport of lactate the administration of the alkaloid did not favor the performance of 1min ESupra or the IMS of the upper and lower limbs in active individuals. / O objetivo deste estudo foi verificar se a suplementação com bicarbonato de sódio (NaHCO3) altera o desempenho durante exercícios supramáximos no ciclismo (ESupra), as variáveis cardiorrespiratórias, e a força muscular isométrica subseqüente. Participaram deste estudo 8 sujeitos do sexo masculino, fisicamente ativos (23,0±4,01anos; 54,69±6,51ml/kg/min-1). Os voluntários foram submetidos a um ESupra de 1min no cicloergômetro, com carga 0,075 kg/peso, após a ingestão de uma solução com 0,3g/kg NaHCO3 ou placebo (PLAC) com 0,045g/kg de NaCl. Em seguida realizaram os testes de força máxima isométrica (FMI) para os membros superiores e inferiores. O NaHCO3 não teve efeito sobre o desempenho no ESupra (497,45±52,47W) comparado ao PLAC (497,97±60,15W). Não foram observados efeitos do ESupra nem da ingestão do NaHCO3 no teste para FMI dos flexores do cotovelo (NaHCO3 pré 38,4±6,6kgf e pós 36,7±7,8kgf; PLAC pré 37,1±6,8kgf e pós 36,2±8,0kgf), como também para a FMI dos extensores do joelho (NaHCO3 pré 84,68±12,36kgf e pós 80,28±11,88kgf; PLAC pré 87,04±16,38kgf e pós 81,20±13,41kgf). Em relação às respostas fisiológicas foi observado um aumento significativo durante o ESupra apenas para o pico de VCO2 (4,93±0,47l/min) na condição NaHCO3 comparado com o PLAC (4,44±0,28l/min), sem diferenças significativas para essa variável durante a recuperação. Não foram observadas diferenças significativas para o VO2 e VE em qualquer momento durante a recuperação. As concentrações de lactato sanguíneo foram diferentes para condição NaHCO3 quando comparado com o PLAC à partir do segundo minuto após o ESupra até o final dos 30min de recuperação. Diante dos resultados encontrados, é provável que o aumento na concentração do lactato sanguíneo após ingestão de NaHCO3 seja decorrente da maior liberação do íon pela musculatura exercitada e/ou pela diminuição da absorção nos outros tecidos, uma vez que não foram apresentados indícios de uma maior produção durante o exercício (i.e. melhora na performance). Além disso, o maior valor de VCO2 pico durante o ESupra sugere um maior tamponamento do H+ gerado pela suplementação com NaHCO3. Apesar de demonstrarmos indícios da ação do bicarbonato sobre o equilíbrio acidobásico e no transporte de lactato, a administração do alcalóide não favoreceu o ESupra de 1min no ciclismo nem a força máxima isométrica de membros superiores e inferiores em indivíduos ativos.

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