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1.
Bioengineering (Basel) ; 10(2)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36829748

RESUMO

The market for wrist-worn devices is growing at previously unheard-of speeds. A consequence of their fast commercialization is a lack of adequate studies testing their accuracy on varied populations and pursuits. To provide an understanding of wearable sensors for sports medicine, the present study examined heart rate (HR) measurements of four popular wrist-worn devices, the (Fitbit Charge (FB), Apple Watch (AW), Tomtom runner Cardio (TT), and Samsung G2 (G2)), and compared them with gold standard measurements derived by continuous electrocardiogram examination (ECG). Eight athletes participated in a comparative study undergoing maximal stress testing on a cycle ergometer or a treadmill. We analyzed 1,286 simultaneous HR data pairs between the tested devices and the ECG. The four devices were reasonably accurate at the lowest activity level. However, at higher levels of exercise intensity the FB and G2 tended to underestimate HR values during intense physical effort, while the TT and AW devices were fairly reliable. Our results suggest that HR estimations should be considered cautiously at specific intensities. Indeed, an effective intervention is required to register accurate HR readings at high-intensity levels (above 150 bpm). It is important to consider that even though none of these devices are certified or sold as medical or safety devices, researchers must nonetheless evaluate wrist-worn wearable technology in order to fully understand how HR affects psychological and physical health, especially under conditions of more intense exercise.

2.
Biosensors (Basel) ; 11(10)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34677347

RESUMO

The myths surrounding women's participation in sport have been reflected in respiratory physiology. This study aims to demonstrate that continuous monitoring of blood oxygen saturation during a maximal exercise test in female athletes is highly correlated with the determination of the second ventilatory threshold (VT2) or anaerobic threshold (AnT). The measurements were performed using a pulse oximeter during a maximum effort test on a treadmill on a population of 27 healthy female athletes. A common behavior of the oxygen saturation evolution during the incremental exercise test characterized by a decrease in saturation before the aerobic threshold (AeT) followed by a second significant drop was observed. Decreases in peripheral oxygen saturation during physical exertion have been related to the athlete's physical fitness condition. However, this drop should not be a limiting factor in women's physical performance. We found statistically significant correlations between the maximum oxygen uptake and the appearance of the ventilatory thresholds (VT1 and VT2), the desaturation time, the total test time, and between the desaturation time and the VT2. We observed a relationship between the desaturation time and the VT2 appearance. Indeed, a linear regression model between the desaturation time and the VT2 appearance can predict 80% of the values in our sample. Besides, we suggest that pulse oximetry is a simple, fairly accurate, and non-invasive technique for studying the physical condition of athletes who perform physical exertion.


Assuntos
Oximetria , Consumo de Oxigênio , Saturação de Oxigênio , Atletas , Feminino , Humanos , Oxigênio
3.
Steroids ; 141: 104-113, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30503386

RESUMO

This article studies the genetic influence of polymorphism of the UGT2B17 gen on the urinary steroid profile and its implications for the anti-doping field. The study presents the results of a triple-blind randomized placebo-controlled crossover trial with healthy athletes submitted to a single dose of 250 mg of testosterone cypionate. Forty urine samples were collected from each participant. Mass spectrometry-based techniques commonly used in Anti-Doping laboratories, were employed to measure the urinary concentration and the Δδ13C values of a selection of target compounds for testosterone (T) administration together with LH. Twelve volunteers were included in the study; the polymorphism was evenly distributed among them. After T administration, the most meaningful change affected the Testosterone/Epitestosterone ratio (T/E) and the urinary concentration of LH. In relation with T/E, the wild type homozygous (ins/ins) group there was a mean relative increase of 30 (CI 95%: 25.2 to 36.7); in the heterozygous mutant (del/ins) group it was 19.8 (CI 95%:15.9 to 24.7); and in the homozygous mutant (del/del) group it was 19.7 (CI 95% 14.9 to 26.2). In the case of LH, it́s observed how LH values decrease significantly after the administration of Testex homogeneously among the three groups. The main outcome was related to the (del/del) group (homozygous mutant), where due to the depressed basal level of the steroid profile, if the longitudinal steroid profile of the athlete was not available, the analysis by GC/MS would not produce an "atypical" result according to the WADA TD2016EAAS despite the T administration. However, the genotyping of the UGT2B17 polymorphism, the follow up of LH and the use of GC-C-IRMS makes it possible to identify most of these samples as Adverse.


Assuntos
Glucuronosiltransferase/genética , Antígenos de Histocompatibilidade Menor/genética , Polimorfismo Genético/genética , Testosterona/análogos & derivados , Adulto , Atletas , Estudos Cross-Over , Cromatografia Gasosa-Espectrometria de Massas , Glucuronosiltransferase/sangue , Glucuronosiltransferase/deficiência , Humanos , Injeções Intramusculares , Masculino , Antígenos de Histocompatibilidade Menor/sangue , Mutação , Testosterona/administração & dosagem , Testosterona/urina
6.
Physiol Rep ; 3(12)2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26668303

RESUMO

The measurement of the testosterone to epitestosterone ratio (T/E ratio) in urine is often used as a marker for testosterone administration in the doping control field. This study examines the frequencies of the different expression forms of the UGT2B17 gene, and assesses their effects on this marker in volunteer subjects. The sample for this descriptive study was composed of male and female athletes aged between 16 and 55 years old who practiced different sports disciplines. All participants underwent a sports-medical physical examination, and subsequently provided 10 urine samples consecutively over a period of 48 h. The dependent variable examined was T/E and the main independent variable was the UGT2B17 gene polymorphism. During 1 year, 1410 urine samples were obtained from 141 athletes. The frequencies of the three genotypes were as follows: wt homozygotes (ins/ins) 48.2% (n = 68), mutant homozygotes (del/del) 12.1% (n = 17), and heterozygotes (ins/del) 39.7% (n = 56). Genotype distributions varied significantly (P < 0.001) according to ethnicity, 80% of Asian subjects being homozygous for the gene deletion (del/del) compared to 6.9% of Caucasian subjects. A multivariate analysis adjusted for genotype, age, sex, and sports discipline revealed that athletes with the del/del polymorphism showed a significantly lower mean T/E than heterozygotes (ins/del). In contrast, homozygous athletes for the gene insertion (ins/ins) showed higher mean T/E ratios than heterozygotes (ins/del). UGT2B17 gene deletion has a strong influence on the T/E ratio in urine, which is the most efficient indicator of testosterone prohormone misuse. Others factors studied seem not to have such an impact. The genotyping of UGT2B17 is an important source of information for understanding steroid profiling in the doping control field; therefore it is suggested that it be included in the Athletes Biological Passport.

7.
Apunts, Med. esport ; 46(169): 23-27, ene.-mar. 2011. ilus
Artigo em Espanhol | IBECS | ID: ibc-88579

RESUMO

La pulsioximetría sirve para determinar el porcentaje de saturación de oxígeno quehay en sangre. Su mayor característica es que se trata de un método no invasivo y relativamenteeconómico. Existen pocos estudios que relacionen pulsioximetría con actividad física, y losestudios que más abundan son los clínicos. Los autores revisan la definición de la oximetría depulso, los fundamentos en los cuales se basa. Se revisan la aplicación de la pulsioximetría alas pruebas de esfuerzo máximo, así como el comportamiento de la saturación de oxígeno ensangre durante la realización de pruebas de esfuerzo máximo. Además, se revisan los diferentesestudios acerca de los valores de saturación de oxígeno en sangre durante la realización deejercicio físico y su correlación con otras variables ventilatorias. Se analizan las consecuenciasdel uso de la pulsioximetría en pruebas de esfuerzo máximo(AU)


Pulse oximetry is used to determine the percentage saturation of oxygen in blood.Its main feature is that it is a noninvasive and relatively inexpensive. There are few studiesrelating physical activity and pulse oximetry with most abundant studies are clinical trials.The authors review the definition of pulse oximetry, the grounds upon which it is based. Wereview the application of pulse oximetry to maximum exercise testing, and the behavior ofoxygen saturation in the blood for testing of maximum effort. In addition, different studies onthe oxygen saturation values in blood during physical exercise and its correlation with otherventilatory variables. We analyze the consequences of the use of pulse oximetry in tests ofmaximal effort(AU)


Assuntos
Humanos , Oximetria/métodos , Teste de Esforço/métodos , Consumo de Oxigênio/fisiologia , Ergometria/métodos , Oxigênio/sangue
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