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1.
Front Sports Act Living ; 6: 1371723, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38689869

RESUMO

Whole-body electromyostimulation has proven to be a highly effective alternative to conventional resistance-type exercise training. However, due to adverse effects in the past, very extensive contraindications have been put in place for the commercial, non-medical WB-EMS market. Considering recent positive innovations e.g., federal regulation, mandatory trainer education, revised guidelines, and new scientific studies on WB-EMS application, we believe that a careful revision of the very restrictive contraindications on WB-EMS is needed. This applies all the more because many cohorts with limited options for conventional exercise have so far been excluded. During a first meeting of an evidence-based consensus process, stakeholders from various backgrounds (e.g., research, education, application) set the priorities for revising the contraindications. We decided to focus on four categories of absolute contraindications: "Arteriosclerosis, arterial circulation disorders", "Diabetes mellitus" (DM), "Tumor and cancer" (TC), "Neurologic diseases, neuronal disorders, epilepsy". Based on scientific studies, quality criteria, safety aspects and benefit/risk assessment of the category, DM and TC were moved to the relative contraindication catalogue, while arteriosclerosis/arterial circulation disorders and neurologic diseases/neuronal disorders/epilepsy were still considered as absolute contraindications. While missing evidence suggests maintaining the status of neurologic diseases/neuronal disorders as an absolute contraindication, the risk/benefit-ratio does not support the application of WB-EMS in people with arteriosclerosis/arterial circulation diseases. Despite these very cautious modifications, countries with less restrictive structures for non-medical WB-EMS should consider our approach critically before implementing the present revisions. Considering further the largely increased amount of WB-EMS trials we advice regular updates of the present contraindication list.

2.
Biol Sport ; 33(1): 71-6, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26929473

RESUMO

In this study, we tested the hypothesis that breathing hyperoxic air (FinO2 = 0.40) while exercising in a hot environment exerts negative effects on the total tissue level of haemoglobin concentration (tHb); core (Tcore) and skin (Tskin) temperatures; muscle activity; heart rate; blood concentration of lactate; pH; partial pressure of oxygen (PaO2) and carbon dioxide; arterial oxygen saturation (SaO2); and perceptual responses. Ten well-trained male athletes cycled at submaximal intensity at 21°C or 33°C in randomized order: first for 20 min while breathing normal air (FinO2 = 0.21) and then 10 min with FinO2 = 0.40 (HOX). At both temperatures, SaO2 and PaO2, but not tHb, were increased by HOX. Tskin and perception of exertion and thermal discomfort were higher at 33°C than 21°C (p < 0.01), but independent of FinO2. Tcore and muscle activity were the same under all conditions (p > 0.07). Blood lactate and heart rate were higher at 33°C than 21°C. In conclusion, during 30 min of submaximal cycling at 21°C or 33°C, Tcore, Tskin and Tbody, tHb, muscle activity and ratings of perceived exertion and thermal discomfort were the same under normoxic and hyperoxic conditions. Accordingly, breathing hyperoxic air (FinO2 = 0.40) did not affect thermoregulation under these conditions.

3.
J Sports Med Phys Fitness ; 54(4): 475-80, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24721989

RESUMO

AIM: This study aimed to quantify the cardiorespiratory, metabolic and hormonal responses of elite open-wheel indoor kart racers. METHODS: Ten male racers (age: 21±3 yrs; height: 1.92±0.06 m, body mass: 76.0±5.9 kg) participated in a racing tournament. Their peak oxygen uptake and heart rate were assessed by a ramp test (100 W, increase 30 W·min-1) in the laboratory. During the racing itself, the cardio-respiratory and accelerometer values were recorded and pre- and post-race levels of blood lactate and salivary cortisol were determined. RESULTS: The average peak values for all of the drivers with respect to oxygen uptake and heart rate were 4.5±0.8 L·min-1 (56.7±7.9 mL·min-1·kg-1) and 193±5 beats·min-1, respectively. Overall, 28.3±3.3 laps were completed during 30-min of racing. Acceleration forces for the entire test averaged 1.20±0.51 G (maximum: 3.30 G), declining from the first 10 min until the end of racing (P<0.03). The oxygen uptake (~20 mL·min-1·kg-1), heart rate (~133 beats·min-1), respiratory exchange ratio (~0.96) and ventilation (~70 L·min-1) observed indicated moderate cardio-respiratory responses. Blood lactate concentration was significantly higher after the race than before but remained at <2 mmol·L-1 (P<0.01; effect size: 1.62). CONCLUSION: There were no differences between salivary cortisol levels before and after the race (P<0.06; effect size: 0.49). Directly after the race, the drivers rated their perceived exertion on Borg's scale as 11.1±1.3. The present data revealed that the psycho-physical exertion associated with a 30-min open-wheel indoor kart race is moderate.


Assuntos
Frequência Cardíaca/fisiologia , Hidrocortisona/análise , Respiração , Saliva/química , Esportes/fisiologia , Humanos , Ácido Láctico/sangue , Masculino , Consumo de Oxigênio/fisiologia , Percepção , Esforço Físico/fisiologia , Estresse Psicológico , Adulto Jovem
4.
Int J Sports Med ; 35(4): 316-22, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24081622

RESUMO

The aim was to compare the acute hormonal response to a single HIT session at the beginning and end of a HIT shock microcycle. 13 male junior triathletes (15.8±1.8 yrs.) performed 16 HIT sessions within a 2 week period. Venous blood samples were collected before and after the first and last HIT session. Significant increases in cortisol (first session +89.7%; last session +70.3%) and hGH (first session +435.1%; last session +314.6%) concentrations were observed after both training sessions (P<0.05). The acute responses of cortisol, hGH, T3, and fT3 were not different between the first and last HIT sessions (P=1.00). Although no acute changes in testosterone were detected after the training sessions, testosterone concentrations were significantly higher at all time points (62.6-80.1%) during the last compared to first training session (P≤0.001). Findings from the present study reveal that 16 sessions of HIT led to significant increases in baseline concentrations of serum testosterone. This might indicate a heightened anabolic state even in junior triathletes. Based on the hormonal data, we conclude that at the end of this 2 week microcycle no familiarization effect was evident and that the training stimulus produced by HIT was still great enough to "stress" the athletes and induce positive training adaptations.


Assuntos
Adaptação Fisiológica , Hormônios/sangue , Educação Física e Treinamento/métodos , Resistência Física/fisiologia , Adolescente , Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Hormônio do Crescimento Humano/sangue , Humanos , Hidrocortisona/sangue , Masculino , Consumo de Oxigênio , Corrida/fisiologia , Natação/fisiologia , Testosterona/sangue , Tri-Iodotironina/sangue
5.
Sportverletz Sportschaden ; 25(4): 227-34, 2011 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-22161265

RESUMO

INTRODUCTION: In competitive sports different types of compression garments (socks, shorts, tights and whole body suits) have become popular. The results of scientific studies regarding their effectiveness, however, are heterogeneous. The aim of this literature review is to (i) survey the scientific data regarding performance enhancing benefits and the support of recovery when applying compression fabrics and (ii) to describe the practical relevance for the application of compression textiles in the competitive sport context. METHOD: In order to detect relevant publications for the present review an internet search using the medical databases "Medline" and "PubMed" was performed. Altogether, 37 studies were analysed. All publications were from the years 1987 to 2010. RESULTS: The literature review showed no general scientific indications regarding the benefit of compression garments in competitive sports. CONCLUSION: In particular, the different study designs and different clothing styles as well as different pressure gradients gave rise to contradictory data.


Assuntos
Vestuário , Bandagens Compressivas , Desempenho Psicomotor/fisiologia , Equipamentos Esportivos , Esportes/fisiologia , Têxteis , Força Compressiva , Humanos
6.
Scand J Med Sci Sports ; 21(6): e421-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21672028

RESUMO

This investigation tested the hypothesis that breathing oxygen-enriched air (F(i)O(2) =1.00) during recovery enhances peak (P(peak)) and mean power (P(mean)) output during repeated high-intensity exercise. Twelve elite male swimmers (21 ± 3 years, 192.1 ± 5.9 cm, 79.1 ± 8.2 kg) inhaled either hyperoxic (HOX) or normoxic (NOX) air during 6-min recovery periods between five repetitions of high-intensity bench swimming, each involving 40 maximal armstrokes. Oxygen partial pressure (pO(2)) and saturation (SO(2)), [H(+)], pH, base excess and blood lactate concentration were measured before and after all intervals. The production of the reactive oxygen species (ROS) hydrogen peroxide was measured before, directly after and 15 min after the test. P(peak) and P(mean) with HOX recovery were significantly higher than with NOX throughout the third, fourth and fifth intervals (P<0.001-0.04). With HOX, electromyography activity was lower during the third, fourth and fifth intervals than during the first (P=0.05-0.001), with no such changes in NOX (P=0.99). There were no differences in blood lactate, pH, [H(+)] or base excess and ROS production at any time point with either HOX or NOX recovery. These findings demonstrate that the P(peak) and P(mean) of elite swimmers performing high-intensity intervals can be improved by exposure to oxygen-enriched air during recovery.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Hiperóxia/terapia , Oxigênio/administração & dosagem , Resistência Física/fisiologia , Natação/fisiologia , Adolescente , Adulto , Alemanha , Humanos , Masculino , Respiração , Adulto Jovem
7.
Int J Syst Bacteriol ; 44(4): 836-8, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7981109

RESUMO

Two-by-two sequence alignment revealed that the levels of homology between 16S rRNA gene sequences of strains belonging to the two biovars of Ureaplasma urealyticum (class Mollicutes) ranged from 98.5 to 98.9%. Within the biovars, three serovars of the T960 biovar exhibited levels of homology of > or = 99.7%, and the four serovars of the parvo biovar exhibited levels of homology of > or = 99.7%. A dendrogram of the Mycoplasma pneumoniae-Ureaplasma clade of the Mollicutes reflected the distinctiveness of the biovars.


Assuntos
DNA Bacteriano/química , DNA Ribossômico/química , RNA Ribossômico 16S/genética , Ureaplasma/genética , Humanos , Homologia de Sequência do Ácido Nucleico
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