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1.
Sensors (Basel) ; 23(7)2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-37050508

RESUMO

Researchers involved in skiing investigations postulate Telemark skiing as an alternative technique to Alpine skiing, which may be associated with lower injury risk. A free heel of the boot, and a boot that enables flexion of the toe, are characteristic features. The aim of this research was to compare three types of turns on Telemark skis, through a biomechanical description of each skiing technique. Seven professional skiers were investigated. Two cameras and the MyoMotion Research Pro system were utilized. Eighteen wireless IMU sensors were mounted on each skier's body. For every skier, five runs were recorded for each of the three turning techniques. Velocity of run, range of movement, angular velocity in joints, time sequences, and order of initialization of movement were obtained. A higher velocity of skiing was obtained during the parallel (14.2 m/s) and rotational turns (14.9 m/s), compared to a low-high turn (8.9 m/s). A comparison of knee angles, revealed similar minimum (18 and 16 degrees) and maximum (143 and 147 degrees) values achieved during the parallel and rotational techniques, which differed considerably from the low-high technique (27 and 121 degrees, respectively). There were no significant differences in trunk rotation angles. A detailed analysis of the Telemark skiing technique revealed novel information on how turns are executed by well-trained skiers and the impact of different approaches.


Assuntos
Esqui , Movimento , Articulação do Joelho , Amplitude de Movimento Articular , Fenômenos Biomecânicos
2.
Sensors (Basel) ; 23(2)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36679425

RESUMO

In the construction of electronic nose devices, two groups of measurement setups could be distinguished when we take into account the design of electronic nose chambers. The simpler one consists of placing the sensors directly in the environment of the measured gas, which has an important advantage, in that the composition of the gas is not changed as the gas is not diluted. However, that has an important drawback in that it is difficult to clean sensors between measurement cycles. The second, more advanced construction, contains a pneumatic system transporting the gas inside a specially designed sensor chamber. A new design of an electronic nose gas sensor chamber is proposed, which consists of a sensor chamber with a sliding chamber shutter, equipped with a simple pneumatic system for cleaning the air. The proposal combines the advantages of both approaches to the sensor chamber designs. The sensors can be effectively cleared by the flow of clean air, while the measurements are performed in the open state when the sensors are directly exposed to the measured gas. Airflow simulations were performed to confirm the efficiency of clean air transport used for sensors' cleaning. The demonstrated electronic nose applies eight Figaro Co. MOS TGS series sensors, in which a transient response caused by a change of the exposition to measured gas, and change of heater voltage, was collected. The new electronic nose was tested as applied to the differentiation between the samples of Ciboria batschiana fungi, which is one of the most harmful pathogens of stored acorns. The samples with various coverage, thus various concentrations of the studied odor, were measured. The tested device demonstrated low noise and a good level of repetition of the measurements, with stable results during several hours of repetitive measurements during an experiment lasting five consecutive days. The obtained data allowed complete differentiation between healthy and infected samples.


Assuntos
Ascomicetos , Nariz Eletrônico , Odorantes
3.
Artigo em Inglês | MEDLINE | ID: mdl-36360677

RESUMO

The physical improvements from strength and resistance training have been known for decades, but the cognitive benefits of this type of activity are not as well-known. The aim of this review article is to provide a summary of studies presenting the effects of strength and resistance training on BDNF in healthy young adults. A systematic search of various electronic databases (PubMed, Web of Science, Science Direct and Google Scholar) was conducted in September 2022. Studies that examined associations between strength training and BDNF in healthy young adults aged 18-30 years were included. The final sample included 10 studies published between 2009 and 2020. The results of this literature review are inconclusive. Based on the results of the 10 studies, there is no clear answer as to whether strength training has positive effects on BDNF in healthy young adults.


Assuntos
Treinamento Resistido , Adulto Jovem , Humanos , Treinamento Resistido/métodos , Fator Neurotrófico Derivado do Encéfalo , Tempo , Força Muscular
4.
Artigo em Inglês | MEDLINE | ID: mdl-36078520

RESUMO

BACKGROUND: Decreased SpO2 during hypoxia can cause cognitive function impairment, and the effects of acute hypoxia on high-order brain functions such as executive processing remain unclear. This study's goal was to examine the impact of an acute normobaric hypoxia breathing session on executive function and biological markers. METHODS: Thirty-two healthy subjects participated in a blind study performing two sessions of single 30 min breathing bouts under two conditions (normoxia (NOR) and normobaric hypoxia (NH), FIO2 = 0.135). The Stroop test was applied to assess cognitive function. RESULTS: No significant difference was observed in the Stroop interference in the "reading" part of the test in either condition; however, there was a significant increase in the "naming" part under NH conditions (p = 0.003), which corresponded to a significant decrease in SpO2 (p < 0.001). There was a significant increase (p < 0.013) in the brain-derived neurotrophic factor (BDNF) level after NH conditions compared to the baseline, which was not seen in NOR. In addition, a significant drop (p < 0.001) in cortisol levels in the NOR group and a slight elevation in the NH group was noticed. CONCLUSIONS: According to these findings, acute hypoxia delayed cognitive processing for motor execution and reduced the neural activity in motor executive and inhibitory processing. We also noted that this negative effect was associated with decreased SpO2 irrespective of a rise in BDNF.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Função Executiva , Hipóxia , Altitude , Atenção , Fator Neurotrófico Derivado do Encéfalo/química , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Cognição , Humanos , Hipóxia/psicologia , Masculino
5.
Artigo em Inglês | MEDLINE | ID: mdl-35409504

RESUMO

This study characterizes high-altitude training camps and their effect on the aerobic capacity of a Polish national team member (M.W.), who was a participant in the PyeongChang 2018 Winter Olympic Games (body weight: 59.6 kg, body height: 161.0 cm, fat mass: 10.9 kg and 18.3% of fat tissue, fat-free mass: 48.7 kg, muscle mass: 46.3 kg, and BMI = 23.0 kg/m2). The tests were conducted in the periods from April 2018 to September 2018 and April 2019 to September 2019 (period of general and special preparation). The study evaluated aerobic and anaerobic capacity determined by laboratory tests, a cardiopulmonary graded exercise test to exhaustion performed on a cycle ergometer (CPET), and the Wingate anaerobic test. Based on the research, training in hypobaric conditions translated into significant improvements in the skater's exercise capacity recorded after participating in the Olympic Winter Games in Korea (February 2018). In the analyzed period (2018-2019), there was a significant increase in key parameters of aerobic fitness such as anaerobic threshold power output (AT-PO) [W]-223; power output POmax [W]-299 and AT-PO [W/kg]-3.50; (POmax) [W/kg]-4.69; and AT-VO2 [mL/kg/min]-51.3; VO2max [mL/kg/min]-61.0. The athlete showed high-exercise-induced adaptations and improvements in the aerobic metabolic potential after two seasons, in which four training camps were held in altitude conditions.


Assuntos
Altitude , Tolerância ao Exercício , Limiar Anaeróbio/fisiologia , Exercício Físico/fisiologia , Teste de Esforço , Humanos , Consumo de Oxigênio/fisiologia
6.
Sci Rep ; 12(1): 1825, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35115578

RESUMO

Vitamin D is necessary for musculoskeletal health, however, the supplementation of vitamin D above the sufficiency level does not bring additional bone mass density (BMD), unlike physical exercise which enhances the bone formatting process. Regular physical activity has been shown to upregulate VDR expression in muscles and to increase circulating vitamin D. Here we investigate whether a single bout of exercise might change 25(OH)D3 blood concentration and how it affects metabolic response to exercise. Twenty-six boys, 13.8 years old (SD ± 0.7) soccer players, participated in the study. The participants performed one of two types of exercise: the first group performed the VO2max test until exhaustion, and the second performed three times the repeated 30 s Wingate Anaerobic Test (WAnT). Blood was collected before, 15 min and one hour after the exercise. The concentration of 25(OH)D3, parathyroid hormone (PTH), interleukin-6 (IL-6), lactate, non-esterified fatty acids (NEFA) and glycerol were determined. 25(OH)D3 concentration significantly increased after the exercise in all boys. The most prominent changes in 25(OH)D3, observed after WAnT, were associated with the rise of PTH. The dimensions of response to the exercises observed through the changes in the concentration of 25(OH)D3, PTH, NEFA and glycerol were associated with the significant increases of IL-6 level. A single bout of exercise may increase the serum's 25(OH)D3 concentration in young trained boys. The intensive interval exercise brings a more potent stimulus to vitamin D fluctuations in young organisms. Our results support the hypothesis that muscles may both store and release 25(OH)D3.


Assuntos
Calcifediol/sangue , Exercício Físico/fisiologia , Músculo Esquelético/fisiologia , Hormônio Paratireóideo/sangue , Aptidão Física/fisiologia , Adolescente , Atletas , Ácidos Graxos não Esterificados/sangue , Glicerol/sangue , Humanos , Interleucina-6/sangue , Ácido Láctico/sangue , Masculino , Projetos Piloto , Testes de Função Respiratória
7.
Artigo em Inglês | MEDLINE | ID: mdl-34886043

RESUMO

In competitive athletes, the differential diagnosis between nonpathological changes in cardiac morphology associated with training (commonly referred to as "athlete's heart") and certain cardiac diseases with the potential for sudden death is an important and not uncommon clinical problem. The use of noninvasive, fast, and cheap analytical techniques can help in making diagnostic differentiation and planning subsequent clinical strategies. Recent studies have demonstrated the role of gut microbiota and their metabolites in the onset and the development of cardiovascular diseases. Trimethylamine (TMA), a gut bacteria metabolite consisting of carnitine and choline, has recently emerged as a potentially toxic molecule to the circulatory system. The present work aims to develop a simple and cost-effective capillary electrophoresis-based method for the determination of TMA in biological samples. Analytical characteristics of the proposed method were evaluated through the study of its linearity (R2 > 0.9950) and the limit of detection and quantification (LOD = 1.2 µg/mL; LOQ = 3.6 µg/mL). The method shows great potential in high-throughput screening applications for TMA analysis in biological samples as a novel potential biomarker of cardiovascular diseases. The proposed electrophoretic method for the determination of TMA in biological samples from patients with cardiac disease is now in progress.


Assuntos
Doenças Cardiovasculares , Microbioma Gastrointestinal , Biomarcadores , Doenças Cardiovasculares/diagnóstico , Humanos , Metilaminas
8.
Artigo em Inglês | MEDLINE | ID: mdl-34682674

RESUMO

Monitoring the training of amateur long-distance cross-country skiers (XCS) can help athletes' achieve a higher exercise capacity and protect their health. The aim of this study was to assess body composition changes and lipid profiles in middle-aged amateur long-distance XCS after four months of training, including specialized roller ski training. The results of the time-to-exhaustion (TTE) test and blood tests and changes in body composition were analyzed with basic descriptive statistics: the paired Wilcoxon test was used to compare the results (initial and final). Spearman's rank correlation coefficient (R) was used to assess the influence of various variables on maximum oxygen uptake (VO2max). The findings show that training of amateur long-distance XCS improved maximal oxygen uptake (p = 0.008) and had a positive effect on fat reduction, measured in percentages (p = 0.038) and in kilograms (p = 0.023), but did not change blood lipids or other parameters. Further research could focus on other aspects of the annual training cycle: the competition period, and women in a larger group of athletes. Training with roller skis and a cross-country skiing training machine (a specialized machine for strengthening the arms and upper body) can support health and prevent obesity, overweight, and cardiovascular disease.


Assuntos
Treino Aeróbico , Esqui , Composição Corporal , Feminino , Humanos , Lipídeos , Pessoa de Meia-Idade , Oxigênio , Consumo de Oxigênio , Resistência Física
9.
Front Physiol ; 12: 743535, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34675820

RESUMO

Background: The influence of high altitude on an organism's physiology depends on the length and the level of hypoxic exposure it experiences. This study aimed to determine the effect of a prolonged sojourn at very high altitudes (above 3,500m) on subsequent sea-level physical performance, body weight, body composition, and hematological parameters. Materials and Methods: Ten alpinists, nine males and one female, with a mean age of 27±4years, participated in the study. All had been on mountaineering expeditions to 7,000m peaks, where they spent 30±1days above 3,500m with their average sojourn at 4,900±60m. Their aerobic and anaerobic performance, body weight, body composition, and hematological parameters were examined at an altitude of 100m within 7days before the expeditions and 7days after they descended below 3,500m. Results: We found a significant (p<0.01) decrease in maximal anaerobic power (MAPWAnT) from 9.9±1.3 to 9.2±1.3W·kg-1, total anaerobic work from 248.1±23.8 to 228.1±20.1J·kg-1, anaerobic threshold from 39.3±8.0 to 27.8±5.6 mlO2·kg-1·min-1, body fat mass from 14.0±3.1 to 11.5±3.3%, and a significant increase (p<0.05) in maximal tidal volume from 3.2 [3.0-3.2] to 3.5 [3.3-3.9] L after their sojourn at very high attitude. We found no significant changes in maximal aerobic power, maximal oxygen uptake, body weight, fat-free mass, total body water, hemoglobin, and hematocrit. Conclusion: A month-long exposure to very high altitude led to impaired sea-level anaerobic performance and anaerobic threshold, increased maximal tidal volume, and depleted body fat mass, but had no effect on maximal aerobic power, maximal oxygen uptake, or hemoglobin and hematocrit levels.

10.
Front Physiol ; 12: 696335, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34290622

RESUMO

BACKGROUND: Few data are available on mountaineers' survival prospects in extreme weather above 8000 m (the Death Zone). We aimed to assess Death Zone weather extremes experienced in climbing-season ascents of Everest and K2, all winter ascents of 8000 m peaks (8K) in the Himalayas and Karakoram, environmental records of human survival, and weather extremes experienced with and without oxygen support. MATERIALS AND METHODS: We analyzed 528 ascents of 8K peaks: 423 non-winter ascents without supplemental oxygen (Everest-210, K2-213), 76 ascents in winter without oxygen, and 29 in winter with oxygen. We assessed environmental conditions using the ERA5 dataset (1978-2021): barometric pressure (BP), temperature (Temp), wind speed (Wind), wind chill equivalent temperature (WCT), and facial frostbite time (FFT). RESULTS: The most extreme conditions that climbers have experienced with and without supplemental oxygen were: BP 320 hPa (winter Everest) vs. 329 hPa (non-winter Everest); Temp -41°C (winter Everest) vs. -45°C (winter Nanga Parbat); Wind 46 m⋅s-1 (winter Everest) vs. 48 m⋅s-1 (winter Kangchenjunga). The most extreme combined conditions of BP ≤ 333 hPa, Temp ≤ -30°C, Wind ≥ 25 m⋅s-1, WCT ≤ -54°C and FFT ≤ 3 min were encountered in 14 ascents of Everest, two without oxygen (late autumn and winter) and 12 oxygen-supported in winter. The average extreme conditions experienced in ascents with and without oxygen were: BP 326 ± 3 hPa (winter Everest) vs. 335 ± 2 hPa (non-winter Everest); Temp -40 ± 0°C (winter K2) vs. -38 ± 5°C (winter low Karakoram 8K peaks); Wind 36 ± 7 m⋅s-1 (winter Everest) vs. 41 ± 9 m⋅s-1 (winter high Himalayan 8K peaks). CONCLUSIONS: 1.The most extreme combined environmental BP, Temp and Wind were experienced in winter and off-season ascents of Everest.2.Mountaineers using supplemental oxygen endured more extreme conditions than climbers without oxygen.3.Climbing-season weather extremes in the Death Zone were more severe on Everest than on K2.4.Extreme wind speed characterized winter ascents of Himalayan peaks, but severely low temperatures marked winter climbs in Karakoram.

11.
Artigo em Inglês | MEDLINE | ID: mdl-33809531

RESUMO

(1) Background: Today's elite alpinists target K2 and Everest in midwinter. This study aimed to asses and compare weather at the summits of both peaks in the climbing season (Everest, May; K2, July) and the midwinter season (January and February). (2) Methods: We assessed environmental conditions using the ERA5 dataset (1979-2019). Analyses examined barometric pressure (BP), temperature (Temp), wind speed (Wind), perceived altitude (Alt), maximal oxygen uptake (VO2max), vertical climbing speed (Speed), wind chill equivalent temperature (WCT), and facial frostbite time (FFT). (3) Results: Most climbing-season parameters were found to be more severe (p < 0.05) on Everest than on K2: BP (333 ± 1 vs. 347 ± 1 hPa), Alt (8925 ± 20 vs. 8640 ± 20 m), VO2max (16.2 ± 0.1 vs. 17.8 ± 0.1 ml·kg-1·min-1), Speed (190 ± 2 vs. 223 ± 2 m·h-1), Temp (-26 ± 1 vs. -21 ± 1°C), WCT (-45 ± 2 vs. -37 ± 2 °C), and FFT (6 ± 1 vs. 11 ± 2 min). Wind was found to be similar (16 ± 3 vs. 15 ± 3 m·s-1). Most midwinter parameters were found to be worse (p < 0.05) on Everest vs. K2: BP (324 ± 2 vs. 326 ± 2 hPa), Alt (9134 ± 40 vs. 9095 ± 48 m), VO2max (15.1 ± 0.2 vs. 15.3 ± 0.3 ml·kg-1·min-1), Speed (165 ± 5 vs. 170 ± 6 m·h-1), Wind (41 ± 6 vs. 27 ± 4 m·s-1), and FFT (<1 min vs. 1 min). Everest's Temp of -36 ± 2 °C and WCT -66 ± 3 °C were found to be less extreme than K2's Temp of -45 ± 1 °C and WCT -76 ± 2 °C. (4) Conclusions: Everest presents more extreme conditions in the climbing and midwinter seasons than K2. K2's 8° higher latitude makes its midwinter BP similar and Temp lower than Everest's. K2's midwinter conditions are more severe than Everest's in the climbing season.


Assuntos
Montanhismo , Altitude , Pressão Atmosférica , Estações do Ano , Tempo (Meteorologia)
12.
J Clin Med ; 10(8)2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33917691

RESUMO

BACKGROUND: On the one hand, hypoxic exposure may result in progressive brain metabolism disturbance, causing subsequent cognitive impairments. On the other hand, it might also enhance neurogenesis and brain vascularization as well as accelerate cerebral blood flow, leading to cognitive function improvement. The aim of this study was to investigate whether progressive stages of normobaric hypoxia (NH) (FIO2 = 13%, FIO2 = 12%, and FIO2 = 11%) differentially affect post-exposure cognitive performance. METHODS: Fifteen physically active men (age = 23.1 ± 2.1) participated in the study. The Stroop test (ST) was applied to assess cognitive function. To generate NH conditions, a hypoxic normobaric air generator was used. RESULTS: We observed an executive function impairment ("naming" interference p < 0.05) after NH exposure (FIO2 = 13%). After exposure at FIO2 = 12% and FIO2 = 11%, no changes were observed in the Stroop test. Also, changes in SpO2 during subsequent NH exposure were observed. CONCLUSIONS: The current investigation shows that executive functions deteriorate after acute NH exposure and this post-exposure deterioration is not proportional to the normobaric hypoxia stages among young physically active males.

13.
Molecules ; 25(23)2020 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-33291490

RESUMO

Fungi and oomycetes release volatiles into their environment which could be used for olfactory detection and identification of these organisms by electronic-nose (e-nose). The aim of this study was to survey volatile compound emission using an e-nose device and to identify released molecules through solid phase microextraction-gas chromatography/mass spectrometry (SPME-GC/MS) analysis to ultimately develop a detection system for fungi and fungi-like organisms. To this end, cultures of eight fungi (Armillaria gallica, Armillaria ostoyae, Fusarium avenaceum, Fusarium culmorum, Fusarium oxysporum, Fusarium poae, Rhizoctonia solani, Trichoderma asperellum) and four oomycetes (Phytophthora cactorum, P. cinnamomi, P. plurivora, P. ramorum) were tested with the e-nose system and investigated by means of SPME-GC/MS. Strains of F. poae, R. solani and T. asperellum appeared to be the most odoriferous. All investigated fungal species (except R. solani) produced sesquiterpenes in variable amounts, in contrast to the tested oomycetes strains. Other molecules such as aliphatic hydrocarbons, alcohols, aldehydes, esters and benzene derivatives were found in all samples. The results suggested that the major differences between respective VOC emission ranges of the tested species lie in sesquiterpene production, with fungi emitting some while oomycetes released none or smaller amounts of such molecules. Our e-nose system could discriminate between the odors emitted by P. ramorum, F. poae, T. asperellum and R. solani, which accounted for over 88% of the PCA variance. These preliminary results of fungal and oomycete detection make the e-nose device suitable for further sensor design as a potential tool for forest managers, other plant managers, as well as regulatory agencies such as quarantine services.


Assuntos
Fungos/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Oomicetos/química , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/química , Nariz Eletrônico , Odorantes/análise , Olfato
14.
Sensors (Basel) ; 20(12)2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32585850

RESUMO

Recent advances in the field of electronic noses (e-noses) have led to new developments in both sensors and feature extraction as well as data processing techniques, providing an increased amount of information. Therefore, feature selection has become essential in the development of e-nose applications. Sophisticated computation techniques can be applied for solving the old problem of sensor number optimization and feature selections. In this way, one can find an optimal application-specific sensor array and reduce the potential cost associated with designing new e-nose devices. In this paper, we examine a procedure to extract and select modeling features for optimal e-nose performance. The usefulness of this approach is demonstrated in detail. We calculated the model's performance using cross-validation with the standard leave-one-group-out and group shuffle validation methods. Our analysis of wine spoilage data from the sensor array shows when a transient sensor response is considered, both from gas adsorption and desorption phases, it is possible to obtain a reasonable level of odor detection even with data coming from a single sensor. This requires adequate extraction of modeling features and then selection of features used in the final model.

15.
J Sports Med Phys Fitness ; 58(5): 591-596, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28474866

RESUMO

BACKGROUND: One of the aims of the study was to describe the physiological factors of young boys participating in artistic gymnastic training and evaluate differences between the levels of aerobic and anaerobic efficiency in this group as compared to the control group. METHODS: The young male gymnasts selected to participate in the present study have been (G) participating in the training process since they were 6 years old (N.=12, age 11-12 y). In the control group (N.=12, age 11-12 y), boys were participating in physical education classes (C). Anaerobic efficiency was evaluated by using a 30 s Wingate Anaerobic Test (WAnT) for arms. Adjusted load was defined on the level of 50 g·kg-1 of body mass. Aerobic efficiency was defined using gradual effort to exhaustion for lower limbs on the cycle ergometer with simultaneous analysis of breathing gases. RESULTS: The test to exhaustion showed that group G achieved lower VO2peak results as compared to group C. The values were respectively: 48.1 mL·kg-1·min-1 and 55.6 mL·kg-1·min-1 (P<0.05). In the examination of anaerobic efficiency for upper limb parameters, total work and mean power were higher in group G than in group C, while the fatigue index (FI) was lower. CONCLUSIONS: It is likely that early specialization in young male gymnasts may influence proper aerobic metabolism development. Executing WAnT using arms in group G was more convenient and precise according to anaerobic efficiency.


Assuntos
Adaptação Fisiológica/fisiologia , Limiar Anaeróbio/fisiologia , Teste de Esforço , Ginástica/fisiologia , Força Muscular/fisiologia , Educação Física e Treinamento , Criança , Ergometria , Teste de Esforço/métodos , Fadiga , Humanos , Extremidade Inferior/fisiologia , Masculino , Fatores de Tempo , Extremidade Superior/fisiologia
16.
J Strength Cond Res ; 32(11): 3207-3215, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29283932

RESUMO

Wolyniec, W, Ratkowski, W, Kasprowicz, K, Jastrzebski, Z, Malgorzewicz, S, Witek, K, Grzywacz, T, Zmijewski, P, and Renke, M. Glomerular filtration rate is unchanged by ultramarathon. J Strength Cond Res 32(11): 3207-3215, 2018-Acute kidney injury (AKI) is reported as a common complication of marathon and ultramarathon running. In previous studies, AKI was diagnosed on the basis of the creatinine level in serum and estimated glomerular filtration rate (eGFR). In this study, we calculated eGFR and also measured creatinine clearance after every 25 km of a 100-km run. Twenty healthy, amateur runners (males, mean age 40.75 ± 7.15 years, mean body mass 76.87 ± 8.39 kg) took part in a 100-km run on a track. Blood and urine were collected before the run, after every 25 km, and 12 hours after the run. Seventeen runners completed the study. There was increase in creatinine, urea, and uric acid observed after 100 km (p < 0.05). The mean increase in creatinine was 0.21 mg·dl (24.53%). Five runners fulfilled the AKI network criteria of AKI. The eGFR according to the modification of diet in renal disease, chronic kidney disease epidemiology collaboration, and Cockcroft-Gault formulas was significantly decreased after the run (p ≤ 0.05). Otherwise, creatinine clearance calculated from creatinine level in both serum and urine remained stable. In contrast to the majority of previous studies, we did not observe any decrease in the kidney function during an ultramarathon. In this study, the creatinine clearance, which is the best routine laboratory method to determine GFR was used. There is no evidence that long running is harmful for kidney.


Assuntos
Creatinina/sangue , Creatinina/urina , Taxa de Filtração Glomerular , Corrida/fisiologia , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Adulto , Atletas , Humanos , Masculino , Pessoa de Meia-Idade , Ureia/sangue , Ureia/urina , Ácido Úrico/sangue , Ácido Úrico/urina
17.
Cryobiology ; 71(3): 398-404, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26475491

RESUMO

The anti-inflammatory effect induced by exposure to low temperature might trigger the endocrine function of muscle and fat tissue. Thus, the aim of this study was to investigate the influence of the whole body cryostimulation (CRY) on irisin, a myokine which activates oxygen consumption in fat cells as well as thermogenesis. In addition, the relationship between hepcidin (Hpc) - hormone regulating iron metabolism, and inflammation was studied. A group of middle aged men (n = 12, 38 ± 9 years old, BMI > 30 kg m(-2)) participated in the study. Subjects were exposed to a series of 10 sessions in a cryogenic chamber (once a day at 9:30 am, for 3 min, at temperature -110 °C). Blood samples were collected before the first cryostimulation and after completing the last one. Prior to treatment body composition and fitness level were determined. The applied protocol of cryostimulation lead to rise the blood irisin in obese non-active men (338.8 ± 42.2 vs 407.6 ± 118.5 ng mL(-1)), whereas has no effect in obese active men (371.5 ± 30.0 vs 343.3 ± 47.6 ng mL(-1)). Values recorded 24 h after the last cryo-session correlated significantly with the fat tissue, yet inversely with the skeletal muscle mass. Therefore, we concluded the subcutaneous fat tissue to be the main source of irisin in response to cold exposures. The applied cold treatment reduced the high sensitivity C-reactive protein (hsCRP) and Hpc concentration confirming its anti-inflammatory effect.


Assuntos
Crioterapia/métodos , Fibronectinas/sangue , Músculo Esquelético/fisiologia , Gordura Subcutânea/fisiologia , Adulto , Humanos , Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Atividade Motora , Obesidade/metabolismo , Obesidade/fisiopatologia , Obesidade/terapia , Aptidão Física
18.
Eur Cytokine Netw ; 25(1): 14-23, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24998353

RESUMO

Inflammation may accompany obesity and a variety of diseases, or result from excessive exercise. The aim of this study was to investigate the anti-inflammatory effect of whole-body cryostimulation on the inflammatory response induced by eccentric exercise under laboratory conditions. The study also sought to establish if cold treatment changes the lipid profile and modifies energy expenditure in young people. Eighteen healthy and physically active, college-aged men volunteered to participate in the experiment. They were divided into two subgroups: CRY- submitted to whole-body cryostimulation, and CONT- a control group. Both groups performed eccentric work to induce muscle damage. Blood samples were collected before and 24 h after the exercise. Over the five days that followed, the CRY group was exposed to a series of 10 sessions in a cryogenic chamber (twice a day, for 3 min, at a temperature of -110̊C). After this period of rest, both groups repeated a similar eccentric work session, following the same schedule of blood collection. The perceived pain was noted 24h after each session of eccentric workout. A 30-minute step up/down work-out induced delayed-onset muscle soreness in both groups. The five-day recovery period accompanied by exposure to cold significantly enhanced the concentration of the anti-inflammatory cytokine IL-10. It also led to a pronounced reduction in levels of the pro-inflammatory cytokine IL-1ß, and reduced muscle damage. The values for IL-10 before the second bout of eccentric exercise in the CRY group were 2.0-fold higher in comparison to baseline, whereas in the CONT group, the concentration remained unchanged. Furthermore, blood concentrations of the pro-inflammatory cytokine IL-1ß fell significantly in the CRY group. The main finding of this study was that a series of 10 sessions of whole body cryostimulation significantly reduced the inflammatory response induced by eccentric exercise. The lipid profile was also improved, but there was no effect on energy expenditure during the exercise.


Assuntos
Colesterol/sangue , Crioterapia/métodos , Exercício Físico/fisiologia , Inflamação/terapia , Mialgia/terapia , Adulto , Temperatura Baixa , Humanos , Inflamação/patologia , Inflamação/prevenção & controle , Mediadores da Inflamação/sangue , Interleucina-10/sangue , Interleucina-1beta/sangue , Masculino , Mialgia/prevenção & controle , Dor/prevenção & controle , Medição da Dor , Adulto Jovem
19.
J Sports Sci Med ; 12(2): 282-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24149807

RESUMO

Heat shock proteins (Hsp) represent proteins' groups, whose protective function, may be induced by heat, reactive oxygen species, cytokines etc. We evaluated blood levels of Hsp27 and Hsp70, and their relation to skeletal muscle damage and inflammation in young tennis players before and after the conditioning camp. Blood samples were collected directly after tournament season, 3-day rest and 14-day conditioning camp that followed. Hydrogen peroxide (H2O2) demonstrated the highest concentration directly after tournament season, which significantly decreased at camp's end. The pro-inflammatory cytokines IL-1ß and TNFα decreased, whereas anti-inflammatory cytokines IL-6 and IL-10 increased after 3d rest and 14d camp. Hsp27 increased after 3d rest and remained so after 14d camp, while Hsp70 decreased from baseline to camp's completion. Hsp27 and Hsp70 correlated significantly with H2O2, IL-1ß and TNFα. Muscle damage, observed as creatine kinase (CK) activity changes, increased after 14d camp similarly to Hsp27 and anti-inflammatory cytokines IL-6 and IL-10. Obtained data allows to conclude that decrease of Hsp27 and increase in pro-inflammatory cytokines could be a good indicator of overreaching. Reverse tendencies in these proteins may verify accuracy of conditioning camp. Finally, this training program caused an increase in the anti-inflammatory cytokines concentrations, improving individual status of recovery. Key PointsThe study demonstrating low grade inflammation-induced by the tournament season in young tennis player.Three days of active rest stimulated the anti-inflammatory response via rise of Hsp27 and anti-inflammatory cytokine IL-10.Observed decrease of blood Hsp70 may support mental recovery.Thirteen-day appropriate training program led to maintaining an immunological response balance.

20.
J Physiol Sci ; 63(5): 333-43, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23744123

RESUMO

This study was aimed to evaluate anti-inflammatory effect of the whole body cryostimulation in obese men. Fourteen subjects (BMI >30 kg m(-2)), divided into two subgroups according to cardiorespiratory fitness: higher (HCF) or lower (LCF), have been exposed to 10 sessions in a cryogenic chamber (-110 °C). Blood samples were collected before, 30 min and 24 h after the first, fifth and last cryostimulation. Coldness exposures affected blood cytokine profile; however, the response depended on subjects' fitness capacity. Concentrations of pro-inflammatory cytokines in the LCF decreased by 19, 6.8, and 7.4 % in IL-6, resistin, and visfatin, respectively. TNFα in the LCF dropped 4.3-fold compared to baseline, while in the HCF, changes were smaller, yet significant. Anti-inflammatory cytokine IL-10 increased in both groups. No changes in adiponectin and leptin were observed in either group. Obtained results suggest that whole body cryostimulation can be a supplementary method for obese in reducing systemic inflammation.


Assuntos
Inflamação/sangue , Inflamação/fisiopatologia , Obesidade/sangue , Obesidade/fisiopatologia , Adiponectina/sangue , Adulto , Temperatura Baixa , Humanos , Interleucina-10/sangue , Interleucina-6/sangue , Leptina/sangue , Masculino , Nicotinamida Fosforribosiltransferase/sangue , Fator de Necrose Tumoral alfa/sangue
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