Aptitude physique et profil métabolique des jeunes diabétiques de type 1 (effets de l'entraînement chez les adolescentes diabétiques de type 1)

Le rôle des facteurs comportementaux (nutrition, activité physique) sur la prévalence des dysfonctions métaboliques chez les adolescentes diabétiques de type 1 est à préciser. Nous montrons que l'altération de l'aptitude physique avec la puberté chez les filles diabétiques est favorisée par une baisse d'activité physique, une prise de masse grasse (étude 1) et s'accompagne d'une altération des réponses sympatho-adrénergiques à l'effort intense (étude 2). L'e tude 3 précise les dysfonctions métaboliques (dont une tendance originale pour l'adiponectine). Celles-ci sont liées à l'inactivité physique et non à l'alimentation. Six mois d'entraînement, améliorent l'aptitude physique, la composition corporelle, le profil apolipoprotéique et limitent l'augmentation de leptine sérique des adolescentes diabétiques (étude 4). L'activité physique apparaît donc comme un moyen thérapeutique de limiter les dysfonctions métaboliques des adolescentes diabétiquesBehavioural factors (nutrition, physical activity) role in the prevalence of metabolic dysfunctions in adolescent girls with Type 1 diabetes remains almost unexplored. In turn, physical activity and fitness levels could be affected by these dysfunctions. Study 1 shows that physical fitness deterioration with puberty in diabetic girls may be linked to a physical activity decrease as well as a body composition alteration and is accompanied (Study 2) by an altered sympatho-adrenergic response to intense exercise. Study 3 specifies, in diabetic adolescent girls, the metabolic dysfunctions (particularly an original pattern for adiponectin). They are associated with physical inactivity but not with dietary intake. Moreover, 6 months physical training improve body composition, physical fitness, apolipoprotein profile, and prevent leptin increase (Study 4). Physical activity may thus be an important therapeutic adjunct for diabetic adolescent girls to manage cardiovascular risk factorsRENNES2-BU Centrale (352382101) / SudocSudocFranceF

Effects of (-)-epicatechin on mitochondria.

Mitochondrial dysfunction is observed in a broad range of human diseases, including rare genetic disorders and complex acquired pathologies. For this reason, there is increasing interest in identifying safe and effective strategies to mitigate mitochondrial impairments. Natural compounds are widely used for multiple indications, and their broad healing properties suggest that several may improve mitochondrial function. This review focuses on (-)-epicatechin, a monomeric flavanol, and its effects on mitochondria. The review summarizes the available data on the effects of acute and chronic (-)-epicatechin supplementation on mitochondrial function, outlines the potential mechanisms involved in mitochondrial biogenesis induced by (-)-epicatechin supplementation and discusses some future therapeutic applications

In Amateur Athletes With Type 1 Diabetes, a 9-Day Period of Cycling at Moderate-to-Vigorous Intensity Unexpectedly Increased the Time Spent in a State of Hyperglycemia, Which Was Associated With Impairment in Heart Rate Variability.

In type 1 diabetes, autonomic dysfunction may occur early as a decrease in heart rate variability (HRV). In populations without diabetes, the positive effects of exercise training on HRV are well-documented. However, exercise in individuals with type 1 diabetes, particularly if strenuous and prolonged, can lead to sharp glycemic variations, which can negatively impact HRV. This study explores the impact of a 9-day cycling tour on HRV in this population, with a focus on exercise-induced glycemic excursions. Twenty amateur athletes with uncomplicated type 1 diabetes cycled 1,500 km. HRV and glycemic variability were measured by heart rate and continuous glucose monitoring. Linear mixed models were used to test the effects of exercise on HRV, with concomitant glycemic excursions and subject characteristics considered as covariates. Nighttime HRV tended to decrease with the daily distance traveled. The more time the subjects spent in hyperglycemia, the lower the parasympathetic tone was. This result is striking given that hyperglycemic excursions progressively increased throughout the 9 days of the tour, and to a greater degree on the days a longer distance was traveled, while time spent in hypoglycemia surprisingly decreased. This phenomenon occurred despite no changes in insulin administration and a decrease in carbohydrate intake from snacks. In sports enthusiasts with type 1 diabetes, multiday prolonged exercise at moderate-to-vigorous intensity worsened hyperglycemia, with hyperglycemia negatively associated with parasympathetic cardiac tone. Considering the putative deleterious consequences on cardiac risks, future work should focus on understanding and managing exercise-induced hyperglycemia

L’exercice aérobie continu apparaît protecteur contre les hyperglycémies de récupération précoce, en période post-absorptive, en comparaison de l’exercice intermittent intense, chez des enfants et adolescents atteints d’un diabète de type 1

International audienceINTRODUCTION-QUESTIONDès le plus jeune âge, l’exercice est une clé de la prise en charge du diabète de type 1 (DT1). Néanmoins, la peur de l’hypoglycémie est un frein majeur à l’activité physique (Livny et coll. 2019). Chez l’adulte atteint de DT1, l’ajout de répétitions de séquences intenses lors d’un exercice continu modéré semble limiter la baisse de glycémie (Guelfi et coll. 2005). L’objectif est d’évaluer l’impact de l’intensité et de la modalité d’exercice sur les excursions glycémiques au décours de l’exercice chez l’enfant/adolescent atteint de DT1.MATERIELS ET METHODESCinq garçons et 7 filles atteints de DT1 (9,8±1,4ans; HbA1c 7 ,5±0,7%) réalisent en période post-absorptive, sur ergocycle, en ordre randomisé (visites espacées de >48h), un exercice continu modéré (CONT) et un exercice intermittent intense (INT) de durée et charge mécanique totale identiques [20min; 50%PWC170 vs. 15sec(150%PWC170)/30sec récupération passive). Lesvariations glycémiques (glycémie capillaire pendant l’exercice et glucose interstitiel à la récupération) sont comparées entre les types d’exercice et une condition sédentaire (SED), en prenant en compte la glycémie initiale, les glucides et l’insuline (covariables dans les modèles mixtes linéaires).RESULTATSAucune hypoglycémie symptomatique n’est survenue. Alors que la glycémie capillaire diminuait à l’exercice pour CONT (−26,5mg/dL), elle restait stable pour INT (différence inter-condition, P<0,05) à partir de valeurs élevées (respectivement de 192,8±39,4 et 179,2±78,3mg/dL, non différentes entre les conditions). Plus les glycémies initiales étaient élevées, plus lesexcursions hyperglycémiques étaient importantes en récupération précoce, mais avec un effet protecteur de l’exercice CONT vs. INT (P<0,05) et vs. SED (P200mg/dL, respectivement 0(0;51,6); 83(0;100) et 100(10;100)%]. Aucun effet des conditions n’est apparu en récupération tardive (8h post-exercice).DISCUSSION-CONCLUSIONLes enfants et adolescents atteints de DT1, pour lesquels la 1ère barrière à l’exercice était pourtant la peur de l’hypoglycémie (score BAPAD1: 4,1±1,6), ont souffert d’excursions hyperglycémiques dans les conditions sédentaire et exercice intermittent intense, alors que l’exercice continu modéré apparaissait protecteur. Les travaux futurs devraient considérer la problématique du risque hyperglycémique à l’exercice, au même titre que celle de l’hypoglycémie.Déclaration d'intérê

Acute running stimulates hippocampal dopaminergic neurotransmission in rats, but has no influence on brain-derived neurotrophic factor.

International audienceHippocampal brain-derived neurotrophic factor (BDNF) protein is increased with exercise in rats. Monoamines seem to play a role in the regulation of BDNF, and monoamine neurotransmission is known to increase with exercise. The purpose of this study was to examine the influence of acute exercise on monoaminergic neurotransmission and BDNF protein concentrations. Hippocampal microdialysis was performed in rats that were subjected to 60 min of treadmill running at 20 m/min or rest. Two hours postexercise, the rats were killed, and the hippocampus was dissected. In experiments without microdialysis, hippocampus and serum samples were collected immediately after exercise. Exercise induced a twofold increase in hippocampal dopamine release. Noradrenaline and serotonin release were not affected. Hippocampal BDNF levels were not influenced, whether they were measured immediately or 2 h after the exercise protocol. Serum BDNF levels did not change either, but serum BDNF was negatively correlated to peripheral corticosterone concentrations, indicating a possible inhibitory reaction to the stress of running. Sixty minutes of exercise enhances dopamine release in the hippocampus of the rat in vivo. However, this increase is not associated with changes in BDNF protein levels immediately nor 2 h after the acute exercise bout. An increased corticosterone level might be the contributing factor for the absence of changes in BDNF

Validation and reliability of the Dutch language version of the Modifiable Activity Questionnaire in healthy subjects

International audienceBackground The Modifiable Activity Questionnaire (MAQ) is a physical activity questionnaire shown to be both valid and reliable in French. After translation and adaptation to Dutch, the objective of the study was to see whether this questionnaire was valid and reliable in the Dutch language and thus could be used as a tool for the detection of exercise levels in a Dutch native-speaking population.Methods After translating and back translating the valid French version of the MAQ into Dutch, the final product of the Dutch version was tested twice in the same population (n = 101) interrupted by 1 week for the assessment of the test–retest reliability. To measure concurrent validity, the valid Dutch version of the IPAQ was filled in at the same time as the MAQ. To measure the construct validity of this assessment tool, a smaller sample size (n = 28) of the total population carried an accelerometer for 1 week.Results The intraclass correlation coefficient for the test– retest reliability was 0.78 (p \ 0.01), suggesting a good test–retest reliability. Pearson’s rho correlation coefficient between the IPAQ and the MAQ was 0.41 (p \ 0.01), suggesting a medium concurrent validity. Pearson corre- lation statistics showed a low, non-significant correlation coefficient (r = 0.243, p = 0.213) when measuring con- struct validity.Conclusion The present study shows that the Dutch lan- guage of the MAQ is reliable and has a medium concurrent validity. Although the construct validity is low, these results are in line with previous validation studies of physical activity questionnaires

Acute cocoa flavanol improves cerebral oxygenation without enhancing executive function at rest or after exercise

Acute exercise-induced improvements in cognitive function are accompanied by increased (cerebral) blood flow and increased brain-derived neurotrophic factor (BDNF) levels. Acute cocoa flavanol (CF) intake may improve cognitive function, cerebral blood flow (in humans), and BNDF levels (in animals). This study investigated (i) the effect of CF intake in combination with exercise on cognitive function and (ii) cerebral hemodynamics and BDNF in response to CF intake and exercise. Twelve healthy men participated in this randomized, double-blind, crossover study. Participants performed a cognitive task (CT) at 100 min after acute 903-mg CF or placebo (PL) intake, followed by a 30-min time-trial. Immediately after this exercise, the same CT was performed. Prefrontal near-infrared spectroscopy was applied during CT and exercise to measure changes in oxygenated (Delta HbO(2)), deoxygenated (Delta HHb), and total haemoglobin (Delta Hb(tot)) and blood samples were drawn and analyzed for BDNF. Reaction time was faster postexercise, but was not influenced by CF. Delta HbO(2) during the resting CT was increased by CF, compared with PL. Delta HbO(2), Delta HHb, and Delta Hb(tot) increased in response to exercise without any effect of CF. During the postexercise cognitive task, there were no hemodynamic differences between CF or PL. Serum BDNF was increased by exercise, but was not influenced by CF. In conclusion, at rest, CF intake increased cerebral oxygenation, but not BDNF concentrations, and no impact on executive function was detected. This beneficial effect of CF on cerebral oxygenation at rest was overruled by the strong exercise-induced increases in cerebral perfusion and oxygenation

L’usage du cannabidiol dans le sport : une bonne idée ?

International audienceObjectives: In this paper, we wish to review the different properties of cannabidiol (CBD) that could be interesting for athletes. News: CBD is one of the most abundant phytocannabinoids, with ∆9-tetrahydrocannabinol, in Cannabis Sativa L. The World Anti-Doping Agency removed CBD from the list of prohibited substances in or out of competition since 2018. With this decision, athletes may be interested to use CBD products derived from Cannabis Sativa L.. Prospects and project: Preclinical studies highlighted anxiolytic, analgesic, anti-inflammatory, neuroprotective properties and also beneficial effects on sleep. This can make CBD interesting for the management of injury, commotion, anxiety and sleep disturbances in athlete population. However, if CBD appears relatively safe, it can induce side effects and mostly when using non-medicinal products. Conclusion: Unfortunately, scientific evidences are scarce and no clinical data are available to recommend appropriately CBD use in athlete population.Objectifs : Dans cet article, nous souhaitons faire le point sur les différentes propriétés du cannabidiol (CBD) potentiellement intéressantes pour le sportif. Actualités : Le CBD est, avec le ∆9-tetrahydrocannabinol, l’un des phytocannabinoïdes les plus abondants du Cannabis Sativa L. Avec la levée de l’interdiction en 2018 du CBD par l’Agence Mondiale Anti-dopage, il est probable que les sportifs se tournent davantage vers les produits au CBD dérivés du Cannabis Sativa L. Perspectives et Projets : Des études précliniques sur le CBD ont montré des effets anxiolytiques, analgésiques, anti-inflammatoires, neuroprotecteurs mais également sur le sommeil. Ces propriétés pourraient être intéressantes dans la gestion des blessures, des commotions, de l’anxiété et des troubles du sommeil. Si le CBD paraît être une molécule sûre, les effets secondaires indésirables existent bel et bien et notamment pour les produits non réglementés. Conclusion : Le manque de preuves scientifiques et le trop peu d’études cliniques appliquées aux sportifs ne permettent pas, pour le moment, de recommander l’utilisation du CBD aux athlètes

Which characteristics and circumstances of exercise do expose to hypo/hyperglycaemic risk and glycaemic variability in children and adolescents with type 1 diabetes: a daily life observational study controlling for confounding impact of food intake and insulin administration

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