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1.
Eur J Sport Sci ; 23(7): 1269-1278, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36475378

RESUMO

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.


Assuntos
Treino Aeróbico , Humanos , Força da Mão , Encéfalo , Terapia por Exercício , Exercício Físico/fisiologia , Resistência Física/fisiologia
2.
Drug Test Anal ; 12(3): 323-330, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31889433

RESUMO

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.


Assuntos
Altitude , Atletas , Dopagem Esportivo/métodos , Hipóxia/sangue , Ensino , Adulto , Estudos Cross-Over , Hemoglobinas/metabolismo , Humanos , Masculino , Contagem de Reticulócitos/estatística & dados numéricos , Método Simples-Cego , Fatores de Tempo , Adulto Jovem
3.
J Neuromuscul Dis ; 6(2): 227-231, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31127730

RESUMO

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.


Assuntos
Ensaios de Uso Compassivo , Oligonucleotídeos/uso terapêutico , Atrofias Musculares Espinais da Infância/tratamento farmacológico , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino
4.
J Neurol Neurosurg Psychiatry ; 84(6): 637-43, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23370617

RESUMO

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.


Assuntos
Anticonvulsivantes/efeitos adversos , Deficiências do Desenvolvimento/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Adulto , Carbamazepina/efeitos adversos , Estudos de Casos e Controles , Criança , Transtornos Globais do Desenvolvimento Infantil/induzido quimicamente , Transtornos Globais do Desenvolvimento Infantil/epidemiologia , Pré-Escolar , Deficiências do Desenvolvimento/epidemiologia , Feminino , Humanos , Lactente , Lamotrigina , Modelos Logísticos , Gravidez , Prevalência , Estudos Prospectivos , Fatores de Risco , Triazinas/efeitos adversos , Ácido Valproico/efeitos adversos
5.
Chest ; 137(3): 707-10, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20202953

RESUMO

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.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Indometacina/efeitos adversos , Apneia Obstrutiva do Sono/induzido quimicamente , Circulação Cerebrovascular/efeitos dos fármacos , Circulação Cerebrovascular/fisiologia , Relação Dose-Resposta a Droga , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia , Recidiva , Apneia Obstrutiva do Sono/fisiopatologia , Ultrassonografia Doppler Transcraniana
7.
J Physiol ; 586(16): 4005-10, 2008 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-18635643

RESUMO

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.


Assuntos
Envelhecimento/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Circulação Cerebrovascular/fisiologia , Exercício Físico/fisiologia , Oxigênio/metabolismo , Aptidão Física/fisiologia , Adolescente , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade
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