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1.
Eur J Appl Physiol ; 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38801445

RESUMEN

Independently, both prolonged uninterrupted sitting and the onset of menopause negatively impact markers of cardiovascular risk. Whether their combination augment these responses additively remains unknown. This study assessed whether prolonged uninterrupted sitting causes greater central and peripheral cardiovascular dysfunction in post-menopausal women compared to pre-menopausal women. To address this, 23 healthy women (13 pre-menopausal [43.77 ± 4.30 years] and 10 post-menopausal [57.20 ± 8.55 years]) sat uninterrupted for 2-h. Carotid-femoral pulse wave velocity (cf-PWV), pulse wave analysis (PWA), lower limb venous pooling (HHb), and calf circumference were assessed pre-and post-sitting using general linear mixed models, with age as a covariate. Changes in MAP over time (both between and within groups) was assessed using a two-way repeated-measures-ANOVA. There were no significant interactions for any outcome measures. However, for cf-PWV, there was a significant main effect of group (Δ = 0.854 ± 0.354 m s-1; p = 0.026, ηp2 = 0.707). For PWA, only heart rate (HR) and pressure forwards (Pf) showed significant main effects 13 of time [Δ = 6 ± 1 bts-min-1, p < 0.001, ηp2 = 0.861] and group [Δ = 3.893 ± 1.450 mmHg, p = 0.016, ηp2 = 0.271], respectively. Both HHb (Δ = 2.737 ± 0.952, p = 0.009, ηp2 = 0.742) and calf circumference (Δ = 0.812 ± 0.128 cm, p < 0.001, ηp2 = 0.863) significantly increased over time. Whilst post-menopausal women demonstrated greater overall arterial stiffness (increased cf-PWV at baseline), there was no difference in cardiovascular response (central or peripheral) to 2-h of prolonged sitting between the pre- and post-menopausal women.

2.
Sports Med ; 54(6): 1459-1497, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38762832

RESUMEN

Hypertension is recognised as a leading attributable risk factor for cardiovascular disease and premature mortality. Global initiatives towards the prevention and treatment of arterial hypertension are centred around non-pharmacological lifestyle modification. Exercise recommendations differ between professional and scientific organisations, but are generally unanimous on the primary role of traditional aerobic and dynamic resistance exercise. In recent years, isometric exercise training (IET) has emerged as an effective novel exercise intervention with consistent evidence of reductions in blood pressure (BP) superior to that reported from traditional guideline-recommended exercise modes. Despite a wealth of emerging new data and endorsement by select governing bodies, IET remains underutilised and is not widely prescribed in clinical practice. This expert-informed review critically examines the role of IET as a potential adjuvant tool in the future clinical management of BP. We explore the efficacy, prescription protocols, evidence quality and certainty, acute cardiovascular stimulus, and physiological mechanisms underpinning its anti-hypertensive effects. We end the review with take-home suggestions regarding the direction of future IET research.


Asunto(s)
Terapia por Ejercicio , Hipertensión , Humanos , Hipertensión/terapia , Hipertensión/prevención & control , Terapia por Ejercicio/métodos , Presión Sanguínea , Ejercicio Físico
3.
Eur J Sport Sci ; 23(7): 1269-1278, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36475378

RESUMEN

Mental fatigue (MF) impairs endurance exercise performance. Brain endurance training (BET) describes the systematic repetition of mentally-fatiguing cognitive tasks designed to build resilience to MF and improve endurance performance. Evidence to date shows that mental training during physical training can benefit post-training exercise performance, however, this concurrent BET approach may not be practical for all settings. Therefore, the current study evaluated the effects of mental training before physical training (prior BET) on exercise performance. A randomised control trial design: pre-test, training (BET, control), post-test. During the pre-test and post-test sessions, participants performed a 5-min rhythmic handgrip task requiring the generation of as much force as possible, a 20-min 2-back working memory task, and another 5-min rhythmic handgrip task. Participants were randomly assigned to a BET (n = 12) or control group (n = 12). Both groups completed the same submaximal rhythmic handgrip training for five weeks (four sessions per week). The BET group also completed 20-min cognitive training (2-back working memory task, incongruent colour-word Stroop task) before each submaximal exercise training session. Endurance performance improved more (p < 0.05) following BET (24%) than physical training alone (12%). Compared to the control group, the BET group showed higher prefrontal oxygenation during the post-test exercise tasks (p < 0.05). Both groups were characterised by the same exertion, motivation, heart rate, and heart rate variability. Mental training before physical training improves endurance performance greater than physical training alone. The benefits of prior BET may be explained, at least in part, by improved prefrontal oxygenation.HighlightsThis study provides further evidence that brain endurance training (BET) improves performance over matched physical training.Prior BET (i.e. engaging in mentally demanding cognitive tasks before physical training) offers another option to enhance fatigue resilience, which expands the use of BET to more sports and potentially higher intensity training where concurrent BET will not be practical.The benefits of prior BET may be explained, at least in part, by improved prefrontal oxygenation.


Asunto(s)
Entrenamiento Aeróbico , Humanos , Fuerza de la Mano , Encéfalo , Terapia por Ejercicio , Ejercicio Físico/fisiología , Resistencia Física/fisiología
4.
Drug Test Anal ; 12(3): 323-330, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31889433

RESUMEN

Exposure to either natural or simulated hypoxia induces hematological adaptations that may affect the parameters of the Athlete Biological Passport (ABP). The aim of the present study was to examine the effect of a novel, mixed hypoxic dose protocol on the likelihood of producing an atypical ABP finding. Ten well-trained middle-distance runners participated in a "live high, train low and high" (LHTLH) altitude training camp for 14 days. The participants spent ˜6 hr.d-1 at 3000-5400 m during waking hours and ˜10 h.d-1 overnight at 2400-3000 m simulated altitude. Venous blood samples were collected before (B0), and after 1 (D1), 4 (D4), 7 (D7), and 14 (D14) days of hypoxic exposure, and again 14 days post exposure (P14). Samples were analyzed for key parameters of the ABP including reticulocyte percentage (Ret%), hemoglobin concentration ([Hb]), and the OFF-score. The ABP adaptive model was administered at a specificity of 99% to test for atypical findings. We found significant changes in [Hb] and Ret% during the hypoxic intervention. Consequently, this led to ABP threshold deviations at 99% specificity in three participants. Only one of these was flagged as an "atypical passport finding" (ATPF) due to deviation of the OFF-score. When this sample was evaluated by ABP experts it was considered "normal". In conclusion, it is highly unlikely that the present hypoxic exposure protocol would have led to a citation for a doping violation according to WADA guidelines.


Asunto(s)
Altitud , Atletas , Doping en los Deportes/métodos , Hipoxia/sangre , Enseñanza , Adulto , Estudios Cruzados , Hemoglobinas/metabolismo , Humanos , Masculino , Recuento de Reticulocitos/estadística & datos numéricos , Método Simple Ciego , Factores de Tiempo , Adulto Joven
5.
J Neuromuscul Dis ; 6(2): 227-231, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31127730

RESUMEN

Nusinersen is the first disease-modifying therapy approved for the treatment of spinal muscular atrophy (SMA), a rare genetic disorder characterized by severe progressive muscular atrophy and weakness. An expanded access program (EAP) provides investigational treatment to patients without other treatment options. An EAP providing nusinersen treatment to individuals with the most severe form of SMA, infantile-onset SMA (consistent with SMA Type I), has enrolled over 800 participants as of September 2018, making it one of the largest in rare disease history. The successes, challenges experienced and opportunities for future consideration during the implementation of the nusinersen EAP are discussed.


Asunto(s)
Ensayos de Uso Compasivo , Oligonucleótidos/uso terapéutico , Atrofias Musculares Espinales de la Infancia/tratamiento farmacológico , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino
6.
J Neurol Neurosurg Psychiatry ; 84(6): 637-43, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23370617

RESUMEN

The aim of this study was to compare the prevalence of diagnosed neurodevelopmental disorders in children exposed, in utero, to different antiepileptic drug treatments. A prospective cohort of women with epilepsy and a control group of women without epilepsy were recruited from antenatal clinics. The children of this cohort were followed longitudinally until 6 years of age (n=415). Diagnosis of a neurodevelopmental disorder was made independently of the research team. Multiple logistic regression analysis revealed an increase in risk of neurodevelopmental disorders in children exposed to monotherapy sodium valproate (VPA) (6/50, 12.0%; aOR 6.05, 95%CI 1.65 to 24.53, p=0.007) and in those exposed to polytherapy with sodium VPA (3/20, 15.0%; aOR 9.97, 95% CI 1.82 to 49.40, p=0.005) compared with control children (4/214; 1.87%). Autistic spectrum disorder was the most frequent diagnosis. No significant increase was found among children exposed to carbamazepine (1/50) or lamotrigine (2/30). An accumulation of evidence demonstrates that the risks associated with prenatal sodium VPA exposure include an increased prevalence of neurodevelopmental disorders. Whether such disorders are discrete or represent the severe end of a continuum of altered neurodevelopmental functioning requires further investigation. Replication and extension of this research is required to investigate the mechanism(s) underpinning the relationship. Finally, the increased likelihood of neurodevelopmental disorders should be communicated to women for whom sodium VPA is a treatment option.


Asunto(s)
Anticonvulsivantes/efectos adversos , Discapacidades del Desarrollo/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Adulto , Carbamazepina/efectos adversos , Estudios de Casos y Controles , Niño , Trastornos Generalizados del Desarrollo Infantil/inducido químicamente , Trastornos Generalizados del Desarrollo Infantil/epidemiología , Preescolar , Discapacidades del Desarrollo/epidemiología , Femenino , Humanos , Lactante , Lamotrigina , Modelos Logísticos , Embarazo , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Triazinas/efectos adversos , Ácido Valproico/efectos adversos
7.
Chest ; 137(3): 707-10, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20202953

RESUMEN

Patients with obstructive sleep apnea (OSA) are predisposed to instability in central ventilatory control during sleep. Increased instability, as reflected in an enhanced expired volume in per unit time loop gain, has been associated with a greater predisposition to upper airway collapse. Here, in an otherwise healthy patient with untreated mild OSA, we describe the further exacerbation of OSA after oral indomethacin administration. The subject was a control subject in part of a study to investigate the effects of altering cerebral blood flow (CBF) on ventilatory responses and sleep. He was administered either placebo or 100 mg of indomethacin orally with 20 mL of antacid 2.5 h before sleep on different days. He was studied overnight by polysomnography, arterial blood gases, and transcranial Doppler ultrasound. Administration of 100 mg of oral indomethacin prior to sleep resulted in an almost doubling of the apnea-hypopnea index (14 to 24/h), compared with placebo. This was due to an increase in apneas, rather than hypopneas. Following the indomethacin, changes in arterial blood gases were unremarkable, but both CBF as indexed using transcranial Doppler ultrasound and CBF reactivity to a steady-state change in CO(2) (CBF-CO(2)) reactivity were reduced, and the ventilatory response to CO(2) was elevated. CBF was also further reduced during nonrapid eye movement sleep following the indomethacin when compared with the control night. Indomethacin-induced reductions in CBF and CBF-CO(2) reactivity and related increases in ventilatory instability may lead to a greater predisposition to upper airway collapse and related apnea; these factors may partly explain the exacerbation of OSA.


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Indometacina/efectos adversos , Apnea Obstructiva del Sueño/inducido químicamente , Circulación Cerebrovascular/efectos de los fármacos , Circulación Cerebrovascular/fisiología , Relación Dosis-Respuesta a Droga , Humanos , Masculino , Persona de Mediana Edad , Polisomnografía , Recurrencia , Apnea Obstructiva del Sueño/fisiopatología , Ultrasonografía Doppler Transcraneal
9.
J Physiol ; 586(16): 4005-10, 2008 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-18635643

RESUMEN

It is known that cerebral blood flow declines with age in sedentary adults, although previous studies have involved small sample sizes, making the exact estimate of decline imprecise and the effects of possible moderator variables unknown. Animal studies indicate that aerobic exercise can elevate cerebral blood flow; however, this possibility has not been examined in humans. We examined how regular aerobic exercise affects the age-related decline in blood flow velocity in the middle cerebral artery (MCAv) in healthy humans. Maximal oxygen consumption, body mass index (BMI), blood pressure and MCAv were measured in healthy sedentary (n = 153) and endurance-trained (n = 154) men aged between 18 and 79 years. The relationships between age, training status, BMI and MCAv were examined using analysis of covariance methods. Mean +/- s.e.m. estimates of regression coefficients and 95% confidence intervals (95% CI) were calculated. The age-related decline in MCAv was -0.76 +/- 0.04 cm s(-1) year(-1) (95% CI = -0.69 to -0.83, r(2) = 0.66, P < 0.0005) and was independent of training status (P = 0.65). Nevertheless, MCAv was consistently elevated by 9.1 +/- 3.3 cm s(-1) (CI = 2.7-15.6, P = 0.006) in endurance-trained men throughout the age range. This approximately 17% difference between trained and sedentary men amounted to an approximate 10 year reduction in MCAv 'age' and was robust to between-group differences in BMI and blood pressure. Regular aerobic-endurance exercise is associated with higher MCAv in men aged 18-79 years. The persistence of this finding in older endurance-trained men may therefore help explain why there is a lower risk of cerebrovascular disease in this population.


Asunto(s)
Envejecimiento/fisiología , Velocidad del Flujo Sanguíneo/fisiología , Circulación Cerebrovascular/fisiología , Ejercicio Físico/fisiología , Oxígeno/metabolismo , Aptitud Física/fisiología , Adolescente , Adulto , Anciano , Humanos , Masculino , Persona de Mediana Edad
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