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1.
Drug Test Anal ; 14(6): 1004-1016, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34994063

RESUMEN

The haematological module of the athlete biological passport (ABP) monitors longitudinal haematological variations that could be indicative of blood manipulation. This study applied a multi-parametric model previously validated in elite cyclists to compare inferred and actual PV variations, whereas the potential influence of the oral contraceptive pill (OCP) cycle on the ABP blood biomarkers and plasma volume (PV) in 14 physically active women taking OCPs was also investigated. Blood and serum samples were collected each week for 8 weeks, and the ABP haematological variables were determined according to the World Anti-Doping Agency guidelines. Transferrin (sTFN), ferritin (FERR), albumin (ALB), calcium (Ca), creatinine (CRE), total protein (TP) and low-density lipoprotein (LDL) were additionally computed as 'volume-sensitive' variables in a multivariate analysis to determine individual estimations of PV variations. Actual PV variations were indirectly measured using a validated carbon monoxide rebreathing method. We hypothesised ABP markers to be stable during a standard OCP cycle and estimated PV variations similar to measured PV variations. Measured PV variations were in good agreement with the predictions and allowed to explain an atypical passport finding (ATPF). The ABP biomarkers, Hbmass and PV were stable over 8 weeks. Significant differences occurred only between Week 7 and Week 1, with lower levels of haemoglobin concentration ([Hb]), haematocrit (HCT) and red blood cell count (RBC)(-4.4%, p < 0.01; -5.1%, p < 0.01; -5.2%, p < 0.01) and higher levels of PV at week 7 (+9%, p = 0.05). We thus concluded that estimating PV variations may help interpret individual ABP haematological profiles in women.


Asunto(s)
Doping en los Deportes , Volumen Plasmático , Atletas , Biomarcadores , Anticoncepción , Femenino , Humanos
2.
J Sports Med Phys Fitness ; 62(8): 1103-1109, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34498826

RESUMEN

BACKGROUND: The influence of regular breath-hold training on hematological variables is not fully understood. We monitored hematological variables in breath-hold divers (BHDs) and active controls over a year expecting both breath-hold training and seasonal effects. METHODS: In 11 recreational BHDs (36±9 years, 177±8 cm, 72±9 kg) and 12 active controls (22±2 years, 174±8 cm, 70±13 kg) monthly blood samples were analyzed with the hematological module of WADA's athlete biological passport. Hemoglobin mass and plasma volume were measured indirectly by the CO-rebreathing method for the last eight months of the study. Breath-hold training sessions were recorded online. Days without breath-hold training, or the number of hours prior to blood sampling when training was realized within the last 24 hours, were recorded. RESULTS: Hematology did not differ significantly between BHDs and controls over the study time (P>0.05). However, hematological values varied significantly over time for both groups suggesting seasonal effects. Blood sampling 19 hours or more after a breath hold training did not indicate any acute effects of breath holding training. CONCLUSIONS: In comparison with a physically active lifestyle, regular breath-hold training does not induce significant variations over one year for the hematological module of the ABP.


Asunto(s)
Contencion de la Respiración , Buceo , Humanos , Estudios Longitudinales
3.
Front Sports Act Living ; 3: 618285, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33817634

RESUMEN

The hematological module of the Athlete Biological Passport (ABP) is used in elite sport for antidoping purposes. Its aim is to better target athletes for testing and to indirectly detect blood doping. The ABP allows to monitor hematological variations in athletes using selected primary blood biomarkers [hemoglobin concentration (Hb) and reticulocyte percentage (Ret%)] with an adaptive Bayesian model to set individual upper and lower limits. If values fall outside the individual limits, an athlete may be further targeted and ultimately sanctioned. Since (Hb) varies with plasma volume (PV) fluctuations, possibly caused by training load changes, we investigated the putative influence of acute and chronic training load changes on the ABP variables. Monthly blood samples were collected over one year in 10 male elite cyclists (25.6 ± 3.4 years, 181 ± 4 cm, 71.3 ± 4.9 kg, 6.7 ± 0.8 W.kg-1 5-min maximal power output) to calculate individual ABP profiles and monitor hematological variables. Total hemoglobin mass (Hbmass) and PV were additionally measured by carbon monoxide rebreathing. Acute and chronic training loads-respectively 5 and 42 days before sampling-were calculated considering duration and intensity (training stress score, TSSTM). (Hb) averaged 14.2 ± 0.0 (mean ± SD) g.dL-1 (range: 13.3-15.5 g·dl-1) over the study with significant changes over time (P = 0.004). Hbmass was 1030 ± 87 g (range: 842-1116 g) with no significant variations over time (P = 0.118), whereas PV was 4309 ± 350 mL (range: 3,688-4,751 mL) with a time-effect observed over the study time (P = 0.014). Higher acute-but not chronic-training loads were associated with significantly decreased (Hb) (P <0.001). Although individual hematological variations were observed, all ABP variables remained within the individually calculated limits. Our results support that acute training load variations significantly affect (Hb), likely due to short-term PV fluctuations, underlining the importance of considering training load when interpreting individual ABP variations for anti-doping purposes.

4.
Int J Lab Hematol ; 42(1): 61-67, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31821749

RESUMEN

INTRODUCTION: The Athlete's Biological Passport (ABP) is a tool for the indirect detection of blood doping. Guidelines from the World Anti-Doping Agency (WADA) require a 2 hours delay after any physical exercise, and to be seated for 10 minutes before collecting an ABP sample. This study investigated posture-related hematological variations with changes in body position during blood sampling. METHODS: Ten successive venous blood samples from 38 subjects were collected in three situations: immediately after 10-minutes of normalized activity (B1), after 10-minutes seated (B2, typical reference sample in an anti-doping context), after a 50 m walk (B3), after 5 and 10-minutes in a seated position again (B4 and B5), and finally after 5-30 minutes supine (B6-B10). Hemoglobin concentration [Hb] and hematocrit (Hct) were determined by flow cytometry to assess putative posture-related variations. RESULTS: Reticulocytes percentage was unchanged in all conditions, [Hb] and Hct were stable after at least 10-minutes in a seated position. Due to shifts in plasma volume, [Hb] and Hct increased slightly but significantly higher after changing posture for a short walk (+0.1 gr/dL [P = .008] and +0.4% [P = .01] respectively), but readjusted to previous levels after only 5 minutes. Supine position (>10 minutes) induced decreases of [Hb] (-0.2 g/dL in average, P < .01) and Hct (-1.1%, in average, P < .01). CONCLUSION: The observed variations in [Hb] and Hct may have minor clinical significance, while they underline the need to follow strict guidelines for posture before and during blood sampling in an anti-doping context.


Asunto(s)
Atletas , Recolección de Muestras de Sangre , Postura , Adulto , Doping en los Deportes/prevención & control , Femenino , Humanos , Masculino
5.
Rev Med Suisse ; 14(613): 1360-1363, 2018 Jul 11.
Artículo en Francés | MEDLINE | ID: mdl-29998639

RESUMEN

In the light of recurring anti-doping news, this article discusses some special cases and extends to the future prospects of developing effective anti-doping strategies. After recalling the current principles of the fight against doping, the use of substances tole-rated at a certain threshold, and the therapeutic use exemptions (TUE) are discussed. Authorized substances with a health risk for athletes are discussed before concluding on the development of the athlete's biological passport as a future common ground for anti-doping and medical follow-up of athletes. In conclusion, this approach emphasizes the imperative dialogue between anti-doping organizations and sports medicine in order to defend good practices preserving the intrinsic value of sport.


En réponse aux actualités antidopage, cet article traite quelques cas particuliers et s'étend aux perspectives futures de développement de stratégies antidopage efficaces. Après avoir rappelé les principes actuels de la lutte antidopage, il aborde l'utilisation de substances tolérées à un certain seuil et évoque les autorisations à usage thérapeutique (AUT). Les substances autorisées mais pouvant présenter un risque sanitaire pour les athlètes sont discutées avant de conclure sur le développement du passeport biologique de l'athlète comme futur terrain commun pour la lutte antidopage et le suivi médical des sportifs. En conclusion, cette approche souligne le dialogue impératif entre organisations antidopage et médecine du sport afin de défendre de bonnes pratiques à même de préserver la valeur intrinsèque du sport.


Asunto(s)
Doping en los Deportes , Deportes , Atletas , Doping en los Deportes/prevención & control , Humanos , Organizaciones , Detección de Abuso de Sustancias
6.
Ann Phys Rehabil Med ; 61(2): 65-71, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29223653

RESUMEN

BACKGROUND: An efficient cardiac rehabilitation programme (CRP) can improve the functional ability of patients after acute coronary syndrome (ACS). OBJECTIVE: To examine the effect of a CRP on parasympathetic reactivation and heart rate recovery (HRR) measured after a 6-min walk test (6MWT), and correlation with 6MWT distance and well-being after ACS. METHODS: Eleven normoweight patients after ACS (BMI<25kg/m2; 10 males; mean [SD] age 61 [9] years) underwent an 8-week CRP. Before (pre-) and at weeks 4 (W4) and 8 (W8) during the CRP, they performed a 6MWT on a treadmill, followed by 10-min of seated passive recovery, with HRR and HR variability (HRV) recordings. HRR was measured at 1, 3, 5 and 10min after the 6MWT (HRR1, HRR3, HRR5, HRR10), then modelized by a mono-exponential function. Time-domain (square root of the mean of the sum of the squares of differences between adjacent normal R-R intervals [RMSSD]) and frequency-domain (with high- and low-frequency band powers) were used to analyse HRV. Participants completed a mental and physical well-being questionnaire at pre- and W8. Exhaustion after tests was assessed by the Borg scale. Pearson correlation was used to assess correlations. RESULTS: HRR3, HRR5 and HRR10 increased by 37%, 36% and 28%, respectively, between pre- and W8 (P<0.05), and were positively correlated with change in 6MWT distance (r=0.58, 0.66 and 0.76; P<0.05). Percentage change in HRR3 was positively correlated with change in well-being (r=0.70; P=0.01). Parasympathic reactivation (RMSSD) was improved only during the first 30sec of recovery (P=0.04). CONCLUSION: Among patients undergoing a CRP after ACS, increased HRR after a 6MWT, especially at 3min, was positively correlated with 6MWT distance and improved well-being. HRR raw data seem more sensitive than post-exercise HRV analysis for monitoring functional and autonomic improvement after ACS.


Asunto(s)
Síndrome Coronario Agudo/rehabilitación , Rehabilitación Cardiaca/métodos , Tolerancia al Ejercicio/fisiología , Frecuencia Cardíaca/fisiología , Recuperación de la Función/fisiología , Síndrome Coronario Agudo/fisiopatología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Prueba de Paso
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