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1.
Herz ; 43(1): 53-60, 2018 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-28116464

RESUMO

Physical activity is nowadays an established therapeutic principle concerning primary and secondary prevention of cardiovascular diseases; therefore, in internal sports medicine various aspects go beyond basic cardiological knowledge and require special medical expertise (sports cardiology). Acute cardiac risk is increased during physical activity; therefore, physical activity should be individually phased under consideration of the whole clinical situation. Physical training results in a functional adaptation of the cardiovascular system. Moreover, a structural adaptation can also be observed in competitive athletes but a differentiation between athlete's heart and cardiomyopathy is sometimes challenging. Preparticipation screening verifiably reduces the incidence of sudden cardiac death in athletes. Respective recommendations for the required diagnostics have been published and statutory health insurances are increasingly more willing to bear the incurred costs. Statistically, doping is more frequent in performance-orientated leisure time sports than in competitive sports. Drugs which are relevant for doping have partially irreversible cardiac side effects.


Assuntos
Doenças Cardiovasculares/fisiopatologia , Coração/fisiopatologia , Esportes/fisiologia , Cardiomegalia Induzida por Exercícios , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Dopagem Esportivo/prevenção & controle , Humanos , Incidência , Programas de Rastreamento , Condicionamento Físico Humano , Resistência Física/fisiologia , Aptidão Física/fisiologia , Fatores de Risco
2.
Int J Sports Med ; 30(11): 834-8, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19876797

RESUMO

Except for traumatic or spontaneous pneumothorax, little information is known about exercise associated pleural pathologies. We present the case of a 22-year-old athlete with symptoms of musculoskeletal disorders of his upper back after a first league soccer match. Clinical examination initially showed a blockage of the costotransversal joints six and seven with subsequent muscular tension representing an interscapulovertebral pain syndrom. Temporary complete pain relief with following severe reoccurrence of symptomes led to further diagnostic procedures after 3 days. Contrast Enhanced Magnetic Resonance Images (CE-MRI) surprisingly revealed an intrathoracic tumenescence in front of the cardiac apex with surrounding pleural effusion. After excluding all alternative diagnosis for unclear pleurisy we assumed an exercise dependent local pleurisy with subsequent pleural effusion due to local friction by a posttraumatic intrathoracic hematoma. Several invasive and non-invasive therapeutical options were discussed in this rare case with a final decision for a conservative strategy. Seven weeks after injury the player was able to return to play. Even if musculoskeletal problems are most likely in high impact athletes, referred pain due to less common disorders has always to be kept in mind.


Assuntos
Exercício Físico , Derrame Pleural/etiologia , Pleurisia/etiologia , Meios de Contraste , Hematoma/complicações , Hematoma/etiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Dor/etiologia , Derrame Pleural/diagnóstico , Pleurisia/complicações , Pleurisia/diagnóstico , Futebol , Adulto Jovem
3.
J Sports Med Phys Fitness ; 47(1): 91-5, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17369804

RESUMO

After 8 years of high performance training in mountain biking, a top female athlete, aged 23, first complained of diffuse, exercise-induced pain in both thighs. Over a period of the next 4 years, a slight but continuous reduction in her performance was observed, despite having maintained her training regime during the first 2 years. Gradually, pain increased, at last occurring even when she climbed a few stairs. This led to a clinical, echo-Doppler, MR-angiographic and DS-angiographic examination, which showed a complete occlusion of the right iliac external artery with good collateralisation. The left external iliac artery evidenced only small intravascular lesions. Surgical treatment (endarterectomy plus patch angioplasty) eliminated the pain completely. Except for a lipoprotein (a) of 114 mg/dL, no other significant risk factors were found. The influence of a genetic (heterocygotic) low APC-ratio of 1.6 and free protein S of 53% is unclear. This is a typical case of a delayed diagnosis in an athlete. A complete occlusion of an external iliac artery is extremely seldom in young in female athletes. With no indication of a general atherosclerotic or inflammatory process nor congenital abnormalities, an exercise-induced, chronic traumatisation may have caused this pathological condition.


Assuntos
Arteriopatias Oclusivas/diagnóstico , Arteriopatias Oclusivas/etiologia , Ciclismo/lesões , Doenças Vasculares Periféricas/diagnóstico , Doenças Vasculares Periféricas/etiologia , Ultrassonografia Doppler , Adulto , Angiografia Digital , Arteriopatias Oclusivas/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Artéria Ilíaca , Angiografia por Ressonância Magnética , Doenças Vasculares Periféricas/cirurgia , Fatores de Risco
4.
Ther Umsch ; 64(3): 181-5, 2007 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-17323291

RESUMO

Performance food in sports is mainly represented by macronutrients and additional nutritional food components. Performance food is often used in sports as so-called ergogenic aids, which are believed to increase exercise capacity, delay fatigue, or enhance the response to training via different mechanisms. Nevertheless, beneficial effects of only a few of these substances is supported by clear scientific evidence. However, a sound scientific base is lacking for most ergogenic aids, and their intake cannot be recommended. This article focuses on some of the most popular macronutrients and nutritional food components which are consumed with the goal of enhancing performance. Some have been shown to exert a positive impact on exercise capacity under specific conditions, or in connection with an optimal timing of ingestion in context with training. Nevertheless, additional research is required to clarify the role of the different performance foods in increasing exercise capacity before more detailed recommendations are possible.


Assuntos
Dieta/métodos , Suplementos Nutricionais , Alimentos Formulados , Alimentos Fortificados , Fenômenos Fisiológicos da Nutrição , Resistência Física/fisiologia , Esportes/fisiologia , Alimentos Orgânicos , Humanos
5.
J Appl Physiol (1985) ; 90(6): 2181-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11356781

RESUMO

The dilution of an intravenous bolus dose of [13C]bicarbonate is used as an estimate for the metabolic rate under certain conditions. It is a consistent finding in all studies that the total amount of intravenous [13C]bicarbonate cannot be recovered as breath 13CO2. In this study, we used a breath-by-breath analysis of 13CO2 to depict the washout of 13CO2 at a high temporal resolution to analyze the extent to which a probable first-pass effect is responsible for the reduced recovery. Eight healthy men were tested at seated rest and with bicycle exercise at a constant load relative to 40 and 75% maximal O2 consumption VO2 max). [13C]bicarbonate (0.0125 g/kg body wt) was administered as an intravenous bolus in each test. Respiratory mass spectrometry was used to derive the course of the end-tidal 13CO2-to-12CO2 ratio from the breath-by-breath data. Approximately 2 min after 13C administration, the washout curve could be fitted well by a two-exponential curve describing a two-compartment mammillary model. Immediately after administration of the bolus dose, an excess peak in the end-tidal 13CO2-to-12CO2 ratio appeared. This peak could not be included in the two-exponential fitting. The area under the first peak resulted in 3.8 +/- 1.3% of the total [13C]bicarbonate dose at rest, 11.5 +/- 2.9% at moderate exercise (40% VO2 max), and 16.9 +/- 4.0% at intensive exercise (75% VO2 max). The first-pass effect had an increasing impact of up to about two-thirds of the lacking bicarbonate with higher exercise intensity. The "loss" of tracer via this first-pass effect must be considered when the results of studies with parenteral administration of [13C]bicarbonate are considered, especially when it is given as a bolus dose and during exercise.


Assuntos
Bicarbonatos/farmacologia , Mecânica Respiratória/efeitos dos fármacos , Adulto , Algoritmos , Área Sob a Curva , Bicarbonatos/administração & dosagem , Bicarbonatos/farmacocinética , Radioisótopos de Carbono , Teste de Esforço , Feminino , Humanos , Injeções Intravenosas , Medidas de Volume Pulmonar , Masculino , Troca Gasosa Pulmonar/fisiologia
6.
J Sports Med Phys Fitness ; 42(3): 354-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12094127

RESUMO

BACKGROUND: Doping has developed into a widespread problem in competitive and high-performance sports due to increasing professionalism in, and commercialization of sports. In contrast, governments and sports organizations have limited financial resources to support all competitive sports. Therefore, further improvement of anti-doping measures can only be achieved through the inclusion and active participation of the athletes themselves. METHODS: In this study, 101 German athletes who are subject to national and international anti-doping tests were asked if doping in sports should be combatted, and which anti-doping measures appeared effective from an athlete's perspective. RESULTS: Ninety-eight point zero two per cent of those questioned felt that measures should be taken against doping in sports. Improved methods of detection and more information on the health risks were favored, as opposed to more severe punishments. In addition, more than two thirds of the athletes supported the introduction of an anti-doping law. The desire for more frequent drug testing was also expressed, despite the distinct invasion of the athletes' privacy. CONCLUSIONS: An anti-doping law, as requested by the athletes, should include measures for educating the public about the health risks involved with doping. In addition, such a law would also make it possible to develop suitable methods of detection.


Assuntos
Dopagem Esportivo/prevenção & controle , Dopagem Esportivo/psicologia , Adolescente , Adulto , Dopagem Esportivo/ética , Feminino , Humanos , Masculino , Opinião Pública , Esportes/psicologia , Medicina Esportiva/legislação & jurisprudência , Inquéritos e Questionários
7.
J Sports Med Phys Fitness ; 42(1): 92-4, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11832881

RESUMO

We are reporting on a 46-year-old man who has suffered of muscle cramps for 4 years, occurring immediately after jogging and playing tennis and lasting for 7-8 hours. Repeated neurological, orthopedic, internal medical and endocrinological examinations showed no pathological findings. Physiotherapy, supplementation of fluids and electrolytes had no effect, nor did medication therapy with muscle relaxants. During spiroergometry without medication, there was an overproportional increase of heart rate and respiratory rate with delayed pCO2 increase after exercise with otherwise normal blood gas levels. This reaction was considerably reduced during spiroergometry under beta-blockade (metoprolol 100 mg); at the same time, the muscle cramps could no longer be induced. Both excessive respiratory regulation and direct hyperadrenergic stimulation should be discussed as the primary cause of the muscle cramps. According to recent findings, b-blockers with intrinsic sympathocomimetic activity should be avoided in therapy.


Assuntos
Traumatismos em Atletas/complicações , Cãibra Muscular/etiologia , Antagonistas Adrenérgicos beta/uso terapêutico , Traumatismos em Atletas/tratamento farmacológico , Teste de Esforço , Humanos , Masculino , Metoprolol/uso terapêutico , Pessoa de Meia-Idade , Cãibra Muscular/tratamento farmacológico
8.
Z Orthop Unfall ; 149(5): 582-7, 2011 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-21984429

RESUMO

Especially in competitive professional sports, associated injuries often imply a specific challenge for the physicians responsible for team sports or tournaments. Besides choosing an optimal treatment strategy, in particular the time of absence from sports is of major relevance, not least because especially an "early return to play" may often qualify or disqualify a sports physician in the perception of the involved persons. Time pressure of a club and an athlete as well as an increasing number of matches per season may often result in inadequate rehabilitation periods or doubtful medical decisions and thus an increasing risk of reinjuries. On the other hand, professional sports may often reveal decisive circumstances, e.g., playing a final or special sportive pretensions of an athlete or a club, when - from a medical point of view - the classical "can or cannot play"-decision seams inappropriate. This article describes the borderline dilemma between responsible medical acting, irrespective of any sportive pressure of an athlete or the club and the need to concurrently take account of special circumstances in professional soccer sports. Furthermore, regarding the actual literature, a new decision model is presented which facilitates a responsible and well-balanced return to play decision respecting all the above named aspects.


Assuntos
Algoritmos , Traumatismos em Atletas/reabilitação , Técnicas de Apoio para a Decisão , Papel do Médico , Futebol/lesões , Medicina Esportiva , Comportamento Cooperativo , Avaliação da Deficiência , Medicina Baseada em Evidências , Alemanha , Comunicação Interdisciplinar , Modalidades de Fisioterapia , Avaliação da Capacidade de Trabalho
9.
Internist (Berl) ; 48(7): 737-42, 2007 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-17426943

RESUMO

Today, doping is no longer limited to the classical drugs with well known effects and side effects. Older generation anabolic steroids are used mainly in fitness and recreational sports. In contrast, due to doping tests, substances used in competitive sports include peptide hormones, medications not yet approved, and even specially developed drugs, such as designer steroids. Of the peptide hormones, particularly growth hormones (human growth hormone), erythropoietin and generics, insulin, and presumably insulin-like growth factor 1 are used. Substance groups potentially relevant for doping are selective androgen receptor modulators and gene therapy drugs. For most of these, there is no knowledge about side effects in healthy individuals, and no adequate doping tests. Therefore, anti-doping measures cannot rely solely on the continual improvement of doping analyses, but should include increased measures for doping prevention. Not only sports organizations, but also governmental agencies should be involved in developing and implementing these measures.


Assuntos
Dopagem Esportivo/métodos , Drogas Ilícitas , Estudos Transversais , Dopagem Esportivo/tendências , Controle de Medicamentos e Entorpecentes/tendências , Previsões , Terapia Genética/tendências , Alemanha , Humanos , Drogas Ilícitas/efeitos adversos , Drogas Ilícitas/farmacocinética , Detecção do Abuso de Substâncias/tendências
10.
Int J Sports Med ; 27(3): 236-41, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16541381

RESUMO

We assessed the use of nutritional supplements among master athletes focusing on their source of information and source of supply of nutritional supplements. 1560 standardized, anonymous questionnaires were distributed among participants of the World Masters Athletics Championships Indoors 2004. These questions were related to biometric parameters, social indicators, training parameters, illicit drugs, and nutritional supplements. Chi2-tests were computed to reveal meaningful associations between basic information (age, gender, family status, children, education, country of origin, disciplines, training years, smoking, and the use of alcohol, illicit drugs, and doping) and the intake of nutritional supplements. Descriptive information on the history of their use of nutritional supplements was also provided. 60.5 % of all participants reported the actual use of nutritional supplements. We found no significant differences between nutritional supplement users and non-users with regard to basic information. The substances predominantly used were vitamins (35.4 %) and minerals (29.9 %). In contrast to elite athletes who use nutritional supplements to increase their athletic performance, master athletes use these substances predominantly for health reasons and, thus, have a closer contact to the health care system. Physicians are their preferred source of information about nutritional supplements. More than half of the interviewed athletes obtain their nutritional supplements from pharmacies or physicians. The results of this study indicate that nutritional supplement users in master athletics show no specific user profile. Since it is not rare for nutritional supplements to contain trace contaminations of anabolic androgenic steroids or pro-hormones, physicians should also inform master competitive athletes of the dangers of testing positive for doping substances due to their intake of nutritional supplements and advise them accordingly.


Assuntos
Suplementos Nutricionais , Esportes , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Dopagem Esportivo , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Minerais/administração & dosagem , Fatores de Risco , Inquéritos e Questionários , Vitaminas/administração & dosagem
11.
Int J Sports Med ; 26(3): 238-43, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15776342

RESUMO

The purpose of the World Anti-Doping Code 2003 and the 2004 Prohibited List is to create a universal international standard to fight doping in competitive sports. The result of this is a whole series of changes for doctors with regard to their work with competitive athletes. The revised definition of doping now includes physicians in the group of persons who can fulfil the elements of a doping offence. Moreover, the mere possession of substances appearing on the Prohibited List represents a violation of anti-doping regulations. The 2004 Prohibited List includes several changes to the Olympic Movement List from 2003. Caffeine, for example, was removed from the list. Cannabinoids, on the other hand, are now prohibited in competition for all sports. The same is true for all forms of glucocorticosteroids. Therapeutic use exemptions in an abbreviated process are possible for the administration of glucocorticosteroids by non-systemic routes, as well as inhalative therapy with the beta-2-agonists formoterol, salbutamol, salmeterol, and termbutalin. In other cases, a therapeutic use exemption is possible using a standard application process. Further changes will become effective in the 2005 Prohibited List. In 2005, it is essential that beta-2-agonists are prohibited in and out of competition. HCG and LH are prohibited for all athletes. Dermatological preparations of glucocorticosteroids are no longer prohibited, and intravenous infusions will be a prohibited method in 2005, except as a legitimate acute medical treatment. In cases of violations of anti-doping regulations where it is permissible for the affected person to furnish proof of exoneration, the burden of proof is not higher than that required to prove the violation. The sanctions provided for in the World Anti-Doping Code follow a principle of rules and exceptions which at first glance seems difficult to understand. In the case of doping violations by physicians, the anti-doping code provides--as a general rule--for exclusion from sports associations for at least four years. Since several of the changes are questionable under constitutional aspects, it remains to be seen whether the World Anti-Doping Code 2003 will allow the achievement of a universal standard to combat doping.


Assuntos
Albuterol/análogos & derivados , Dopagem Esportivo/prevenção & controle , Glucocorticoides/uso terapêutico , Papel do Médico , Guias de Prática Clínica como Assunto , Esportes/normas , Agonistas Adrenérgicos beta/uso terapêutico , Albuterol/uso terapêutico , Comportamento Competitivo , Etanolaminas/uso terapêutico , Fumarato de Formoterol , Humanos , Xinafoato de Salmeterol
12.
J Sports Sci ; 23(7): 723-6, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16195022

RESUMO

A significant proportion of nutritional supplements manufactured worldwide contain non-listed contaminations with anabolic-androgenic steroids (AAS), whose ingestion may lead to positive doping test results. This will lead to the suspension of, and sanctions against, the athlete, since this group of active substances is prohibited by the anti-doping code of the World Anti-Doping Agency as well as by sports associations not connected with this agency. Considerable financial losses are often the consequence for a banned athlete. Based on an amendment to the law governing the manufacture and prescription of drugs (AMG) in Germany in 1997 and an increasingly extensive interpretation of the term "drug" by the Federal Supreme Court, preparations containing anabolic steroids or their precursors are to be classified as drugs and, therefore, are subject to compulsory declaration as stated by the AMG. If this obligation is not adhered to, the result may be a claim for damages by the athlete against the manufacturer of a preparation, if the athlete took the preparation thinking it was harmless as judged by the Anti-Doping regulations, but was then found to be positive in doping tests. The judges in the first case before the county court in Stuttgart decided in favour of the claim for damages with respect to lost bonuses, loss of earnings and accrued legal costs by a soccer player who tested positive and was therefore suspended. Based on the evidence presented, the court came to the decision that the soccer player's positive test result was due to the ingestion of nutritional supplements containing non-listed AAS. This procedure could set a precedent for other states to demonstrate that athletes who had tested positive due to contaminated nutritional supplements are not without legal protection.


Assuntos
Anabolizantes/análise , Dopagem Esportivo/legislação & jurisprudência , Dopagem Esportivo/métodos , Estudos de Amostragem , Futebol , Suplementos Nutricionais , Dopagem Esportivo/prevenção & controle , Feminino , Alemanha , Humanos , Estudos Longitudinais , Masculino , Apoio Nutricional/efeitos adversos , Fatores de Risco
13.
Int J Sports Med ; 26(7): 563-8, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16195990

RESUMO

The determination of anaerobic capacity (AC) using treadmill ergometry is problematic from a methodological, as well as a technical standpoint. In this study, a procedure from Monod and Scherrer was modified to examine whether realistic magnitudes of AC could be determined using three subject groups with different levels of anaerobic training. The subject groups consisted of 10 untrained (UT), 10 aerobic-trained runners (AeT), and 10 anaerobic-trained 400-meter sprinters (AnT). In two separate test series, first the VO2max was determined and second the so-called individual anaerobic threshold (IAT) was used to determine the aerobic power for all subjects. Then all subjects completed a series of sprints with increasing speeds above the VO2max, from which the work output from each test was calculated. Through linear regression, the point of intersection of the regression line with the y-axis was defined as global AC. The results show typically higher VO2max and IAT for AeT (62.2 ml x kg(-1) x min(-1), 14.7 km x h(-1)) compared to UT (53.2 ml x kg(-1) x min(-1); 11.2 km x h(-1)) and AnT (56.7 ml x kg(-1) x min(-1); 11.8 km x h(-1)). AC was significantly higher in AnT (4.1 +/- 0.58 kJ) compared to AeT (1.8 +/- 0.65 kJ) and UT (3.2 +/- 0.68 kJ). The determined absolute values of AC are considerably lower than of comparable examinations using bicycle ergometry. One reason for such an underestimation of AC could be that the horizontal work done during exercise on a treadmill was not taken into enough consideration. Another explanation is that the magnitude of the calculated AC values shows a dependency on the duration of each sprint test. In addition, the critical velocity for all subjects was found to be higher than for IAT, which consequently leads to an underestimation of AC. Moreover, the absolute level of the AC values appears to depend on the endurance of the comparison groups. It can then be concluded that the applied procedure allows for a differentiation amongst a variously trained collective, but does not allow a correct absolute determination of the AC.


Assuntos
Limiar Anaeróbio/fisiologia , Teste de Esforço/métodos , Tolerância ao Exercício/fisiologia , Medicina Esportiva/métodos , Adulto , Humanos , Estilo de Vida , Masculino , Corrida/fisiologia , Análise e Desempenho de Tarefas
14.
Int J Sports Med ; 24(3): 173-8, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12740734

RESUMO

With the expanding use of portable heart rate (HR) monitors in endurance sports, HR is increasingly used as a marker for exercise intensity. Hereby, HR at the so-called individual anaerobic threshold (IAT) is one possible reference point. However, once determined, it is often attempted to apply HR recommendations from one type of ergometry to different kinds of exercises. We examined whether HR at IAT and at 4 mmol x l -1 blood lactate is predictable from cycling to running and vice versa. Data of 371 subjects (304 male, 67 female) were analyzed. All subjects underwent an incremental test on a treadmill (TR, starting speed 6 or 8 km x h -1, increments 2 km x h -1 every 3 min) and on a bicycle ergometer (BE, start at 50 Watt, increments 25 or 50 Watt every 3 min). IAT was determined at a net increase of lactate concentration of 1 - 5 mmol x l -1 above lactate concentration at lactate threshold for running (as in: Med Sci Sports Exerc 1998, 30 (10); 1552 - 1557) and 1.0 mmol x l -1 for cycling. A maximum time span of three weeks was allowed between the tests. We found that heart rate at IAT or at 4 mmol x l -1 blood lactate did not correlate between cycling and running. A sports specific test seems to be a prerequisite for reliable heart rate recommendations.


Assuntos
Ciclismo/fisiologia , Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Corrida/fisiologia , Adulto , Limiar Anaeróbio/fisiologia , Ergometria/métodos , Feminino , Humanos , Ácido Láctico/sangue , Masculino , Fatores Sexuais
15.
Artigo em Inglês | MEDLINE | ID: mdl-8076624

RESUMO

Buffering is a factor which influences performance in short and middle-term endurance by compensating exercise acidosis. The aim of the study was to establish whether respiration parameters are a relative measure of buffering capacity and to study the influence of buffering on specific performance parameters. Three groups (each of ten subjects) with defined degrees of adaptation [untrained (UT), aerobic-trained (AeT) and elite 400-m runners (AnT) with a best time of 48.47 +/- 0.98 s] were examined in an incremental multi-stage test on the treadmill. Breath-by-breath gas analysis was performed using mass spectrometry and computer routines. Serum lactate concentrations were determined at each exercise level until subjective exhaustion. A value for the relative functional buffering capacity (relFB) was calculated using exercise metabolic parameters. Running speed at the lactate threshold was used as the starting point of buffering. The start of respiratory compensation of acidosis (RCP) was taken as the endpoint of buffering. RCP was determined at the point of decrease in end-tidal CO2 content (CO2-ET). RelFB was given in percent of buffering to running speed at RCP. Group AnT attained the same maximum performance data (maximum running speed, maximum rate of O2 consumption) as group AeT. However, these values were attained in group AnT with a significantly higher relFB (AnT: 31.0 +/- 3.2% vs. AeT: 15.7 +/- 3.9%, P < 0.0001), while a higher lactate threshold indicated a greater oxidative capacity in AeT (AeT: 3.07 +/- 0.26 m.s-1 vs. AnT: 2.68 +/- 0.22 m.s-1).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Exercício Físico/fisiologia , Lactatos/sangue , Aptidão Física/fisiologia , Adulto , Humanos , Concentração de Íons de Hidrogênio , Ácido Láctico , Masculino , Consumo de Oxigênio , Troca Gasosa Pulmonar , Corrida
16.
Int J Sports Med ; 21(6): 419-23, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10961517

RESUMO

The so-called excess-CO2 in physical exertion results stoichiometrically directly from the quantity of protons bound in bicarbonate buffering. This situation is used in determining the ventilatory threshold (VT). However, the extent to which the degree and increase characteristics of excess-CO2 can be used as an equivalent to blood lactate concentrations is uncertain. To investigate this relationship, 21 healthy men exercised on a cycle ergometer (starting at 50 watt, increases of 50 watt every 3 minutes) to subjective exhaustion. To evaluate the characteristics of this increase, a slope constant lambda was calculated in relation to performance for both the blood lactate concentration (lambda lactate) and the cumulated excess-CO2 (lambda CO2 excess). The start of the lactate increase (LT) and excess-CO2 (VT) showed good intercorrelation (VT=2.27+0.98 x LT; r=0.914; P<0.001). Mean lambda lactate and lambda CO2 excess were of similar dimensions in all subjects (69.3 +/- 39.8 watt vs. 80.11 +/- 15.7 watt), but a minority of the subjects (n=7) showed a considerably more gradual increase for the excess-CO2 to the maximum. Since in addition there was no significant correlation between the absolute values for maximum lactate concentrations and the cumulative excess-CO2, an interindividual prediction of lactate concentrations from the excess-CO2 would be difficult. It is an open question, however, whether perhaps additional performance-limiting factors, such as the ventilation or the buffering capacity, may be included when measuring the excess-CO2 so that this parameter could be more a measure for the formation rate of new lactate than the blood lactate concentration alone.


Assuntos
Dióxido de Carbono/sangue , Exercício Físico/fisiologia , Ácido Láctico/sangue , Adulto , Teste de Esforço , Humanos , Masculino , Consumo de Oxigênio , Análise de Regressão
17.
Int J Sports Med ; 20(8): 527-31, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10606216

RESUMO

Lower metabolic and cardiocirculatory reactions to eccentric compared to concentric exercise are known for large muscle groups. The extent of exercise reaction depends on the muscle mass involved and moreover differs between the various muscle groups, while it is unclear to which extent cardiovascular and metabolic reactions and differences between the types of work exist in the shoulder, also it is not known whether these reactions differ according to training status. Lactate production (LA), heart rate (HR), and blood pressure (BP) were examined following eccentric and concentric shoulder movements in 16 male gymnasts (GN) and 15 male untrained subjects (US). Differentiation was made according to the types of work for peak torque (PT) and local muscle endurance (LME). Following eccentric exercise, the increase of LA and HR was clearly lower than following concentric exercise (p<0.05). No difference was observed between the groups. Diastolic BP showed no changes, whereas systolic BP was higher following concentric exercise. Eccentric PT was higher than concentric PT in GN within a test-retest variability of 15%. LME showed a lower degree of fatigue under eccentric conditions, independent of the group. It is concluded that eccentric exercise of the shoulder leads to lower metabolic and cardiocirculatory reactions than concentric exercise, in spite of higher peak torque and less fatigue. Exercises consisting of a high proportion of eccentric movement may thus be beneficial in the therapy of shoulder complaints, especially in patients with cardiovascular disease.


Assuntos
Pressão Sanguínea/fisiologia , Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Ácido Láctico/sangue , Fadiga Muscular/fisiologia , Ombro/fisiologia , Adulto , Análise de Variância , Terapia por Exercício/métodos , Humanos , Masculino , Músculo Esquelético/fisiologia , Aptidão Física/fisiologia , Estudos Prospectivos , Lesões do Ombro
18.
Arch Pharm (Weinheim) ; 330(9-10): 307-12, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9396390

RESUMO

The aim of our study was to investigate structure activity relationship following the replacement of the 6-phenyl substituent at the 6,7-diaryl-2,3-dihydropyrrolizine template by various heteroaromatic residues. In this context we developed a new, efficient, and highly sensitive test method for the screening of dual cyclooxygenase-1 (COX-1) and 5-lipoxygenase (5-LOX) inhibitors. We used human platelets as a source of COX-1 and human PMNLs as a source of 5-LOX. Both cell types were isolated from the same volume of blood. PGE2 and LTB4 respectively were determined by highly selective and sensitive ELISA kits, using monoclonal antibodies. For a single determination at most 0.5 mL whole blood is needed.


Assuntos
Araquidonato 5-Lipoxigenase/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase/síntese química , Inibidores de Ciclo-Oxigenase/farmacologia , Isoenzimas/efeitos dos fármacos , Inibidores de Lipoxigenase/síntese química , Inibidores de Lipoxigenase/farmacologia , Prostaglandina-Endoperóxido Sintases/efeitos dos fármacos , Pirróis/síntese química , Pirróis/farmacologia , Plaquetas/efeitos dos fármacos , Plaquetas/enzimologia , Ciclo-Oxigenase 1 , Feminino , Humanos , Masculino , Proteínas de Membrana , Neutrófilos/efeitos dos fármacos , Neutrófilos/enzimologia
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