Physical Activity Counselling Received Throughout Pregnancy and Effect on Behaviours: A Quasi-Experimental Study.

OBJECTIVES: The objective was to examine the frequency of physical activity (PA) counselling for pregnant women over the course of their pregnancies and the effect on the women's PA behaviour. METHODS: A quasi-experimental study was conducted in the maternity unit of a hospital. In total, 72 pregnant women were randomized into a control or intervention group. Counselling about PA was dispensed to the women in the intervention group throughout pregnancy by health professionals who had been sensitized to its importance and the recommendations. The women in the control group received the usual consultation content. The PA behaviour of pregnant women in the intervention group who reported receiving PA counselling was evaluated. The counselling and PA levels were evaluated by chi-square tests and repeated measures analysis of variance, respectively. RESULTS: Overall, the women received little counselling in accordance with the recommendations, although the intervention group women received this counselling more frequently (P = 0.049). All women in the intervention group who reported receiving counselling throughout pregnancy limited their decline in PA compared with those in the control group. The decline in total PA among normal-weight and overweight pregnant women was reduced in the intervention group (respectively, P = 0.043 and P = 0.044). CONCLUSION: Our intervention showed the effectiveness of counselling on PA behaviour, although the effect was observed at the end of pregnancy. Training and sensitizing for professionals should be strengthened to ensure that counselling in line with the recommendations to maintain or increase PA levels throughout pregnancy is provided.

One hour of internal precooling with cold water/menthol enhances cycling performance in a heat/wet stress environment: A pilot study.

The aim of this study was to compare precooling durations before aerobic performance in a heat/ wet stress environment. Seven heat-acclimated and trained male cyclists completed 1-hour time trials in a hot and humid environment. Before each trial, the cyclists drank (1) a neutral beverage at 23°C during the 1-hour pre-exercise resting period (Neutral), (2) an ice-slush/menthol beverage at -1°C during the last 30 min of the resting period (Pre-30), or (3) an ice-slush/menthol beverage at -1°C during the 1-hour pre-exercise resting period (Pre-60). In each condition, the cyclists drank cold water/menthol at 3°C during the exercise. Performance was significantly higher in Pre-60 than in Pre-30 and Neutral conditions (condition effect: F(2,12)=9.50, p=0.003, ηp2=0.61), with no difference between Pre-30 and Neutral. During the resting period, rectal temperature was significantly lower in Pre-60 than in Pre-30 and Neutral (condition effect: F(2,12)=4.48, p=0.035, ηp2=0.43). Thermal comfort and rating of perceived exertion were not affected by conditions, but thermal sensation was positively affected in Pre-60 during the resting period (Friedman condition effect at 40, 45 and 60 minutes: χ2=6.74; df=2; p=0.035; χ2=8.00; df=2; p=0.018; χ2=4.90; df=2; p=0.086, respectively) and exercise (Friedman condition effect at 5 and 60 minutes: χ2=6.62; df=2; p=0.037; χ2=6.50; df=2; p=0.039, respectively). This study shows that 1 hour of precooling with an ice-slush and menthol beverage (1) improved performance in a 1-hour time trial, (2) had a cumulative effect with a cold water/menthol beverage during this exercise, and (3) decreased rectal temperature during the resting period. This precooling method enhances cycling performance in a heat/wet stress environment.

Relationship Between Actual and Perceived Locomotor and Ball Skills Competence Among Children: A Person-Centered Approach.

This study examined whether profiles varying in actual and perceived locomotor and ball skill competencies would be identified and whether these profiles would differ in relation to children's characteristics. Participants were 127 (70 boys; 57 girls) French-speaking Canadian children (5-11 years). Actual and perceived motor competencies were, respectively, measured using the Test of Gross Motor Development - Third version and the pictorial scale of Perceived Movement Skill Competence. Latent profile analyses revealed four profiles: (1) Non-Alignment: Devaluation (children underestimated their slightly below average competencies; 17.9%); (2) Non-Alignment: Overestimation (children overestimated their slightly below average competencies; 24.7%); (3) Non-Alignment: Underestimation (children slightly underestimated their above average competencies; 24.9%); (4) Alignment: Low Competence (children displayed accurate but slightly below average competencies; 32.5%). Girls were more likely to correspond to profiles 1 and 4, older children and children more frequently involved in physical activity/sport practice were more likely to correspond to profile 3, and younger children were more likely to correspond to profile 2. These results emphasise the importance of considering the alignment between perceived and actual motor competencies. They also indicate that age and physical activity/sport practice were associated with higher competencies, whereas girls and younger children were associated with lower competencies.

Oxidative stress, inflammation, blood rheology, and microcirculation in adults with sickle cell disease: Effects of hydroxyurea treatment and impact of sickle cell syndrome.

Inflammation and oxidative stress play a key role in the pathophysiology of sickle cell disease (SCD). However, the potential influence of different sickle genotypes, or hydroxyurea (HU) treatment, on these factors remains poorly documented. The present study compared several plasma markers of inflammation and oxidative stress, as well as microvascular function, between patients with sickle SC disease (HbSC, n = 19) and patients with sickle cell anemia (HbSS) under hydroxyurea (HU) treatment (n = 16), or not (n = 13). Hemorheological parameters and levels of inflammatory (IL-6, IL-8, IFN-γ, MCP-1, MIP-1ß, TNF-α) and oxidative stress (AOPP, MDA, MPO) markers were determined. Peripheral microcirculatory cutaneous blood flow and immediate microvascular response to local heat were evaluated using laser Doppler flowmetry. Oxidative stress and inflammation were lower in HbSC patients and HbSS patients under HU therapy compared to HbSS patients not treated with HU. Blood viscosity was higher in HbSC than in HbSS patients treated with or not with HU. Vasodilation response of the cutaneous microcirculation to heat stress was higher in HbSS patients receiving HU treatment. Our results clearly established that both sickle cell genotype and HU treatment modulate inflammation and oxidative stress.

Influence of High-Pressure Polymerization on Mechanical Properties of Denture Base Resins.

PURPOSE: The purpose of this study was to study the influence of high-pressure (HP) polymerization on the mechanical properties of denture base PMMA resins compared with conventional thermopolymerization and PMMA discs for digital dentures. MATERIALS AND METHODS: Three groups of blocks were prepared: Probase Hot (Ivoclar Vivadent, Lichtenstein) conventionally heat polymerized at 100°C, Probase Hot heat polymerized at 100°C under HP (200 MPa) and Ivobase CAD (Ivoclar Vivadent, Lichtenstein). Samples for mechanical/physical (n = 30) and samples for viscoelastic (n = 10) characterizations were cut from the blocks. Flexural strength (σf ), elastic modulus (Ef ), hardness, density (ρ), flexural deformation at maximal flexural stress, flexural load energy (Ur ) and viscoelastic properties (E', E'', Tanδ, Tg ) were analyzed using one-way ANOVA (α = 0.05), Scheffé multiple means comparisons (α = 0.05) and Weibull statistics (for σf ). SEM images of the fractured surfaces were obtained. RESULTS: Ef , E', E'' and density of HP polymerized Probase hot were significantly higher than conventional heat polymerized Probase Hot, whereas Tg was significantly lower and σf , Tanδ, hardness, flexural deformation at maximal flexural stress, Ur were not significantly different. The highest values for σf , flexural deformation at maximal flexural stress, Ur and Weibull modulus were obtained with Ivobase CAD. CONCLUSION: HP polymerization does not significantly increase the mechanical properties of denture base resins.

Skin Application of 4% Menthol Enhances Running Performance in Hot and Humid Climate.

Aerobic performance is negatively impacted by tropical climate due to impairment of thermoregulatory mechanisms. We tested the hypothesis that a torso application of a 4% menthol solution would have the same effect on a best performance 10-km run as an external use of cold water. Thirteen trained male athletes completed four outdoor 10-km runs (T=29.0±1.3°C, relative humidity 59.0±13.6%) wearing a tee-shirt soaked every 2-km either in a cold (~6°C) or warm/ambient (~28°C) solution, consisting in water or in a 4% menthol solution, (CTL, MENT-Amb, CLD and MENT-CLD). Run performances were improved from 4.8 to 6.1% in CLD (51.4±5.5 min), MENT-Amb (52.2±5.9 min) and MENT-CLD (51.4±5.1 min) conditions (vs. CTL, 55.4±8.4 min, P<0.05), without differences between these three conditions, whereas heart rate (177±13bpm), body temperature (38.7±0.6°C) and drink ingestion (356±170 g) were not modified. Thermal sensation after running was lower in MENT-CLD (vs. CTL, P<0.01) and thermal acceptability was higher in CLD and MENT-Amb (vs. CTL, P<0.05), but thermal comfort, feeling scale and rate of perceived exertion remained unchanged. The use of menthol on skin enhances aerobic performance in a tropical climate, and no differences in performance were observed between menthol and traditional percooling strategies. However, combining both menthol and traditional percooling brought no further improvements.

Beneficial Influence of Mindfulness Training Promoted by Text Messages on Self-Reported Aerobic Physical Activity in Older Adults: A Randomized Controlled Study.

Inactivity is known to have harmful effects on the physical and mental health of older adults. This study used a randomized, parallel trial design to evaluate whether daily text prompts to practice mindfulness would have a positive impact on the time that adults aged 50 years or older spend in aerobic physical activity. The participants were recruited from a certified fitness center and divided into mindfulness and control groups. For 4 weeks, they were exposed to the experimental conditions, with or without the morning text message. In the morning message condition, the mindfulness groups received a text message with the instruction to practice audio-guided mindfulness for 10 min, and the control group received a placebo message. The participants practicing mindfulness reported significantly more weekly minutes of aerobic physical activity and higher intrinsic motivation than the control participants. Mindfulness training was effective at increasing aerobic physical activity duration and might complement physical activity programs.

Leg asymmetry and muscle function recovery after anterior cruciate ligament reconstruction in elite athletes: a pilot study on slower recovery of the dominant leg.

The aim of this study was to examine performance in hopping tests in male athletes after anterior cruciate ligament reconstruction (ACLR) in the 4-to-6 months post-surgery period. A total of 36 athletes (24 ACLR and 12 controls) participated in this study. The ACLR group consisted of athletes who had undergone an ACLR on their dominant side (ACL DG n=16) or non-dominant side (ACL NDG n=8). Participants completed the following functional tests: a single-leg hop (SLH), single-leg triple hop (SL3H) and single-leg counter movement jump (SLCMJ), then the limb symmetry index (LSI) was calculated. There were no significant differences between the dominant and the non-dominant legs for all functional tests when comparing the ACL DG and the ACL NDG at 6 months after surgery. At 6 months after ACLR, the LSI of the two legs was within acceptable values, whether the athlete had the operation on their dominant or non-dominant leg (except the mean LSI for the ACL DG in the SLCMJ test). Furthermore, the control group showed higher performances as compared to the ACL group for all variables at 6 months after surgery, despite acceptable LSI. We concluded that an early return to "full participation to training" is not recommended in participants who have undergone an ACLR with patellar tendon grafts.

Exercise interventions to improve balance for young people with intellectual disabilities: a systematic review and meta-analysis.

AIM: To conduct a systematic review and meta-analysis of the effects of exercise interventions designed to improve balance in young people with intellectual disabilities. METHOD: A systematic literature search was performed on 10 databases. Studies in press or published in English in a peer-reviewed journal were included if: (1) participants were young people with intellectual disabilities; (2) exercise interventions were designed to improve balance; and (3) they used quasi-experimental or experimental designs. Studies focusing only on a specific subpopulation of young people with intellectual disabilities or having a specific physical characteristic were excluded. Risk of bias was assessed for randomization, allocation sequence concealment, blinding, incomplete outcome data, selective outcome reporting, and other biases. RESULTS: The search strategy identified 937 articles and 15 studies, published between 1991 and 2017, that met the inclusion criteria. Exercise intervention groups showed a significant and larger improvement in static (pooled effect size, Hedges' g=0.98) and dynamic (g=1.34) balance compared with the control groups. However, although the pooled improvement of static-dynamic balance was large (g=2.80), the result was non-significant. None of the subgroup analyses were significant, except for the improvement in: (1) static balance (higher in quasi-experimental than in experimental studies); and (2) dynamic balance (higher in young people with a mild vs a mild-moderate intellectual disability). INTERPRETATION: The reviewed exercise interventions seem to represent an effective means for improving the static and dynamic balance of young people with intellectual disabilities. However, the present findings should be considered as preliminary given the small number of studies and their limitations. WHAT THIS PAPER ADDS: Exercise intervention results in large and significant improvements in static and dynamic balance in young people with intellectual disabilities. Exercise intervention results in a large but non-significant improvement in static-dynamic balance. Static balance improvement was significantly higher in quasi-experimental versus experimental studies. Dynamic balance improvement was significantly higher in young people with mild versus mild-moderate intellectual disability. No significant differences related to age group, balance measures, and components of exercise intervention were found.

EJERCICIOS PARA MEJORAR EL EQUILIBRIO EN JÓVENES CON DISCAPACIDAD INTELECTUAL: UNA REVISIÓN SISTEMÁTICA Y UN METAANÁLISIS: OBJETIVO: Realizar una revisión sistemática y un metaanálisis sobre los efectos del ejercicio diseñado para mejorar el equilibrio en jóvenes con discapacidad intelectual. METODO: Se realizó una búsqueda sistemática en 10 bases de datos. Fueron incluidos estudios impresos o publicados en ingles en publicaciones revisadas por sus pares; que a su vez : (1) los participantes eran jóvenes con discapacidad intelectual, (2) las intervenciones a través del ejercicio fueron diseñados para mejorar el equilibrio, (3) fueron usados diseños experimentales o cuasi experimentales. Los estudios que se enfocaron únicamente a una subpoblación de jóvenes con discapacidad intelectual y los que tenían características físicas específicas fueros excluidos. El riesgo de sesgo fue evaluado para detectar randomización, ocultamiento de secuencia de alocación, estudios ciegos, datos de resultado incompletos, reporte de resultados seleccionados y otros sesgos RESULTADOS: La estrategia de búsqueda identificó 937 artículos y 15 estudios, publicados entre 1991 y 2017, que cumplieron los criterios de inclusión. El grupo con intervención de ejercicios mostró una mejora significativa en el balance estático (tamaño del efecto agrupado, g=0.98) y balance dinámico (g=1.34) comparado con el grupo control. Sin embargo, aunque la mejoría combinada del balance estático y dinámico fue grande (g=2.80), el resultado no es significativo. Ninguno de los subgrupos analizados fue significativo, excepto por la mejora en: (1) balance estático (mayor en los estudios cuasi-experimentales que en los experimentales) y (2) balance dinámico (mayor en gente joven con discapacidad intelectual leve que en gente con discapacidad intelectual leve -moderado). INTERPRETACION: La revisión de intervenciones con ejercicio parece representar un método eficaz para mejorar el equilibrio estático y dinámico en jóvenes con discapacidad intelectual. Sin embargo, los hallazgos deben ser considerados como preliminares por la pequeña cantidad de estudios y sus limitaciones.

INTERVENÇÕES COM EXERCÍCIOS PARA MELHORAR O EQUILÍBRIO PARA JOVENS COM DEFICIÊNCIA INTELECTUAL: UMA REVISÃO SISTEMÁTICA E METANÁLISE: OBJETIVO: Conduzir uma revisão sistemática e metanálise sobre os efeitos das intervenções com exercícios desenhadas para melhorar o equilíbrio em jovens com deficiência intelectual. MÉTODO Uma revisão sistemática da literature foi realizada em 10 bases de dados. Estudos in press ou publicados em inglês em revistas revisadas por pares foram incluídos se: 1) os participantes fossem jovens com deficiência intellectual; 2) intervenções com exercícios foram aplicadas visando melhorar o equilíbrio e 3) usaram desenhos experimentais ou quasi-experimentais. Estudos com enfoque em apenas uma sub-população específica de jovens com deficiência intelectual ou que tinham alguma característica física específica foram excluídos. O risco de viés foi avaliado para randomização, sequência de alocação selada, cegamento, resultados incompletes, relato seletivo de resultados, e outros vieses. RESULTADOS: A estratégia de busca identificou 937 artigos e 15 estudos, publicados entre 1991 e 2017, que atenderam aos critérios de inclusão Os grupos sob intervenção com exercícios mostraram significativa e maior melhora no equilíbrio estático (tamanho do efeito agrupado de Hedges g=0,98) and dinâmico (g=1,34) comparados com os grupos controle. Entretanto, embora a melhora agrupada no equilíbrio estático-dinâmico tenha sido grande (g=2,80), o resultado não foi significativo. Nenhuma das análises de subrupos foi significativa, exceto para a melhora em: (1) equilíbrio estático (maior nos estudos quasi-experimentais que nos experimentais) e (2) equilíbrio dinâmico (maior em jovens com deficiência intelectual leve versus leve-moderada). INTERPRETAÇÃO: As intervenções com exercícios revisadas parecem representar um meio efetivo de melhorar o equilíbrio estático e dinâmico de jovens com deficiência intelectual. No entanto, os achados presentes devem ser considerados preliminaries dado o pequeno número de estudos e suas limitações.

Metabolic response to oral glucose tolerance test performed in neutral and warm environmental temperature.

Objective: Hot environments are associated with impaired glucose metabolism at rest in healthy humans. The purpose of this study was to explore the contribution of key glucoregulatory hormones and biomarkers to this altered glucose tolerance. Methods: The effects of ambient temperature on glucose tolerance and its determinants were assessed with a 3-hr oral glucose tolerance test (OGTT) administered to 19 healthy young men and women at 22 °C and 31 °C. Results: The glucose response amplitude was greater in warm environment (AUC 904 ± 151 vs. 721 ± 89 mmol/l·180 min at 31 °C and 22 °C, respectively, p < .001). There was no significant effect of environmental temperature on insulin, growth hormone or pancreatic polypeptide concentrations (all p > .17). The cortisol response to the glucose load was reduced 30, 60, 90 and 120 minutes postload at 31 °C compared with 22 °C (p = .001). The interleukin-6 concentration was also lower in the session at 31 °C (p = .043). Conclusion: We conclude that the effects of environmental temperature on the glucoregulatory hormones and biomarkers reported in this study do not explain the exaggerated increase in blood glucose after a glucose load taken in a warm environmental temperature. Precis statement: This work demonstrates in healthy men and women that the ingestion of glucose elicits an exaggerated increase in blood glucose when the environmental temperature is warm.

Validation of a Photoplethysmographic Heart Rate Monitor: Polar OH1.

This study assessed the validity of a photoplethysmographic heart rate (HR) monitor, the Polar OH1 in various sports performed in ecological conditions: running, cycling, soccer, kayaking, walking, tennis and fitness. Seventy trained athletes (56 males, 14 females) wore the Polar OH1 armband and the H7 chest belt during training. A total of 390 h and 38 min of recording were compared using a 20-bpm window to assess data quality, and Bland-Altman agreements and ICC analyses were used to test accuracy. Linear regression analyses evaluated the HR accuracy and correlation with skin tone. Training loads (TRIMPs) were compared for each session. Reliability was high for endurance sports (>99%) and lower for sports involving arm movements (92~95%). Biases were slightly negative for all sports, whereas widths of limits of agreement varied from 7-20bpm. Bland-Altman agreements were all under 5% except tennis, kayak and fitness. HR accuracy was positively correlated to skin tone (p<0.05). Finally, TRIMPs from the OH1 device were inferior to criterion's (except walking and soccer), within a 3% range from reference. Hence, OH1 represents a valid tool to monitor instantaneous HR and training load, especially for endurance sports.

Fundamental movement skills in children and adolescents with intellectual disabilities: A systematic review.

BACKGROUND: This systematic review is a synthesis of studies concerning: (a) mastery, deficits, and/or delays in fundamental movement skills (FMS) among children and adolescents with intellectual disabilities; (b) comparisons of FMS between children and adolescents with intellectual disabilities and those with typical development (TD); and (c) correlates of FMS. METHOD: A systematic electronic search was performed in 12 databases. Seventeen studies, published between 1951 and 2017, met the inclusion criteria. RESULTS: Children with intellectual disabilities exhibited a lack of mastery and deficits/developmental delays in FMS. They tended to have significantly lower FMS performance than children with TD. Adolescents with intellectual disabilities had developmental delays in balance skills, but were not compared with adolescents with TD. Mastery or deficits in FMS were not explored. Several variables were significantly correlated with FMS among children and adolescents with intellectual disabilities. CONCLUSION: In future studies, FMS should be examined as an important outcome among children and adolescents with intellectual disabilities.

Text Messages Promoting Mental Imagery Increase Self-Reported Physical Activity in Older Adults: A Randomized Controlled Study.

OBJECTIVE: This study tested whether text messages prompting adults 50 years of age and older to perform mental imagery would increase aerobic physical activity (APA) duration using a randomized parallel trial design. METHOD: Participants were assigned to an Imagery 1, Imagery 2, or placebo group. For 4 weeks, each group was exposed to two conditions (morning text message vs. no morning text message). In the morning message condition, the imagery groups received a text message with the instruction to mentally imagine performing an APA, and the placebo group received a placebo message. All participants received an evening text message of "Did you do your cardio today? If yes, what did you do?" for 3 days per week. RESULTS: Participants of the imagery groups reported significantly more weekly minutes of APA in the morning text message condition compared with the no morning message condition. CONCLUSION: Electronic messages were effective at increasing minutes of APA.

Association between oxidative stress and vascular reactivity in children with sickle cell anaemia and sickle haemoglobin C disease.

Oxidative stress and haemolysis-associated nitric oxide (NO) depletion plays a crucial role in the development of vasculopathy in sickle cell anaemia (SS). However it remains unknown whether oxidative stress and haemolysis levels influence vascular function in patients with sickle haemoglobin C disease (SC). Microvascular response to heat (using Laser Doppler flowmetry on finger), oxidative stress biomarkers, NO metabolites, endothelin-1 and haematological parameters were compared between patients with SS and SC. Vascular function, oxidative and nitrosative markers were also measured in healthy (AA) children. SS and SC had increased plasma advanced oxidation protein products (AOPP), malondialdehyde, plasma antioxidant activities and NO end products, compared to AA. SC had lower catalase activity compared to AA and SS. Haemolytic rate, glutathione peroxidase and nitrotyrosine concentrations were significantly increased in children with SS compared to SC and AA. SS and SC had impaired microvascular reactivity compared to AA. In SS, the plateau phase of the response to local thermal heating was negatively associated with nitrotyrosine and AOPP. No association between vascular function parameters and oxidative stress markers was observed in SC. Mild haemolysis in SC, compared to SS, may limit oxidative and nitrosative stress and could explain the better preserved microvascular function in this group.

Micro- and macrovascular function in children with sickle cell anaemia and sickle cell haemoglobin C disease.

It is unclear whether vascular function is affected similarly in children with sickle cell anaemia (SS) and children with sickle haemoglobin C (SC) disease. Therefore, we compared micro and macrovascular functions in healthy (AA) children, children with SS and SC disease, and assessed their association with physical activity. Participants (24 SS, 22 SC and 16 AA), were compared in terms of 1) thermal hyperaemic response (finger pad warming to 42°C) measured by Laser Doppler techniques, 2) arterial stiffness determined by pulse wave velocity, 3) daily energy expenditure related to moderate and intense physical activities estimated by questionnaire and 4) fitness level, evaluated by the six-minute walk test. Response to heating differed between SS, SC and controls. Peripheral microvascular reactivity was lower and pulse wave velocity higher in SS compared to AA. SC had blunted microvascular reactivity in response to heating compared to AA but pulse wave velocity was not different within the two groups. Physical activity and fitness levels were markedly lower in sickle cell patients compared to healthy controls but no association was observed with vascular function. Microvasodilatory reserve is decreased in both SS and SC patients but only SS patients were also characterised by impaired macrovascular function.

Cerebral and muscle microvascular oxygenation in children with sickle cell disease: Influence of hematology, hemorheology and vasomotion.

The present study investigated cerebral and muscle hemoglobin oxygen saturation (tissue oxygen index, TOI) in children with sickle cell anemia (SS), sickle cell hemoglobin C disease (SC) and healthy children (AA). TOI was measured by near-infrared spectroscopy (NIRS) and spectral analysis of the TOI variability was used to assess flowmotion and vasomotion. Arterial oxyhemoglobin saturation (SpO2), hemorheological and hematological parameters were also measured in SS and SC children. Both TOI were lower in SS compared to both AA and SC children, with SC exhibiting lower values than AA children. Cerebral vasomotion expressed in absolute values was enhanced in SS compared to AA and SC children. Muscle vasomotion did not differ between the three groups. Hematocrit, SpO2 and red blood cell deformability were positively associated with cerebral TOI in SS children. We demonstrated that 1) cerebral and muscle TOI were markedly decreased in SS children while the decrease of TOI was milder in SC children, 2) cerebral TOI level was associated with several biological markers in SS children only and 3) cerebral vasomotion was enhanced in SS, possibly to counterbalance the effects of chronic cerebral hypoxia.

Which side of the balance determines the frequency of vaso-occlusive crises in children with sickle cell anemia: Blood viscosity or microvascular dysfunction?

Vascular resistance and tissue perfusion may be both affected by impaired vascular function and increased blood viscosity. Little is known about the effects of vascular function on the occurrence of painful vaso-occlusive crises (VOC) in children with sickle cell anemia (SCA). The aim of the present study was to determine which side of the balance (blood viscosity or vascular function) is the most deleterious in SCA and increases the risk for frequent hospitalized VOC. Microvascular function, microcirculatory oxygenation and blood viscosity were determined in a group of 22 SCA children/adolescents at steady state and a group of 13 healthy children/adolescents. Univariate analyses demonstrated blunted microvascular reactivity during local thermal heating test and decreased microcirculatory oxygenation in SCA children compared to controls. Multivariate analysis revealed that increased blood viscosity and decreased microcirculatory oxygenation were independent risk factors of frequent VOC in SCA. In contrast, the level of microvascular dysfunction does not predict VOC rate. In conclusion, increased blood viscosity is usually well supported in healthy individuals where vascular function is not impaired. However, in the context of SCA, microvascular function is impaired and any increase of blood viscosity or decrease in microcirculatory oxygenation would increase the risks for frequent VOC.

Impaired glucose tolerance after brief heat exposure: a randomized crossover study in healthy young men.

A high demand on thermoregulatory processes may challenge homoeostasis, particularly regarding glucose regulation. This has been understudied, although it might concern millions of humans. The objective of this project was to examine the isolated and combined effects of experimental short-term mild heat exposure and metabolic level on glucoregulation. Two experimental randomized crossover studies were conducted. Ten healthy young men participated in study A, which comprises four sessions in a fasting state at two metabolic levels [rest and exercise at 60% of maximal oxygen uptake (O2) for 40 min] in two environmental temperatures (warm: 31°C and control: 22°C). Each session ended with an ad libitum meal, resulting in similar energy intake across sessions. In study B, 12 healthy young men underwent two 3 h oral glucose tolerance tests (OGTTs) in warm and control environmental temperatures. Venous blood was sampled at several time points. In study A, repeated measure ANOVAs revealed higher postprandial serum glucose and insulin levels with heat exposure. Glycaemia following the OGTT was higher in the warm temperature compared with control. The kinetics of the serum glucose response to the glucose load was also affected by the environmental temperature (temperature-by-time interaction, P=0.030), with differences between the warm and control conditions observed up to 90 min after the glucose load (all P<0.033). These studies provide evidence that heat exposure alters short-term glucoregulation. The implication of this environmental factor in the physiopathology of Type 2 diabetes has yet to be investigated.

The Association of Body Fat and Leisure Time Physical Activity Called into Question for Asian Indians.

OBJECTIVE: Thrifty genotypes may predispose to type 2 diabetes and body fat (%BF) excess through a differentiated relationship between physical activity and body fat. We explored this hypothesis in Asian Indians, a population thought to be thrifty. METHODS: Three hundred and nine Guadeloupian adolescents responded to the modifiable activity questionnaire. Their body fat was assessed by bioimpedancemetry. We first studied the relationship between %BF and leisure time physical activity (LTPA). We then explored the associations of ethnicity with this relationship in a subgroup of 93 Asian Indians matched with 93 controls for age, sex, and LTPA class. The alpha risk retained was .05. RESULTS: The analyses showed that Asian Indians had higher %BF even when matched with controls for age, sex and LTPA quartile, and the relationship between LTPA and %BF observed in controls was not evidenced in Asian Indians. CONCLUSIONS: The higher %BF in Asian Indians remained significant even when they were matched with controls for age, sex and LTPA quartile, and their LTPA was not associated ‒ or was at least less robustly associated ‒ with %BF. These findings are consistent with the hypothesis of thriftiness in Asian Indians, with the weaker relationship of high LTPA and low %BF a possible path to thriftiness.

Intensity, recovery kinetics and well-being indices are not altered during an official FIFA futsal tournament in Oceanian players.

Physiological responses (intensity and recovery kinetics) and well-being indices were examined during a 4-day FIFA international tournament. Ten outfield New Caledonian players (age: 25.5 ± 3.8 years; height: 170 ± 7 cm; weight: 70.7 ± 8.6 kg) were assessed during the four matches. Players' aerobic and anaerobic capacities were measured before the tournament while heart rate (HR), intra-matches recovery and well-being indices (Hooper index) were measured throughout the tournament. HR (168 ± 8 bpm), exercise intensity (83.4 ± 2.3% of HR reserve) and recovery indices were similar throughout the tournament. Well-being indices were largely alike during the tournament while rating of perceived exertion increased throughout the tournament that was not associated with HR or well-being indices. High aerobic and anaerobic capacities were associated with high match intensities and slow recovery indices. In summary, match intensity assessed by HR, recovery kinetics and well-being of Oceanian futsal players were not modified during a 4-day FIFA futsal tournament. Assessment of aerobic and anaerobic capacities may be useful to select players for optimal performance during this type of international tournament.