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1.
Nutrients ; 12(5)2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32365848

RESUMO

We investigated the impact of nutrient intake on hydration biomarkers in cyclists before and after a 161 km ride, including one hour after a 650 mL water bolus consumed post-ride. To control for multicollinearity, we chose a clustering-based, machine learning statistical approach. Five hydration biomarkers (urine color, urine specific gravity, plasma osmolality, plasma copeptin, and body mass change) were configured as raw- and percent change. Linear regressions were used to test for associations between hydration markers and eight predictor terms derived from 19 nutrients merged into a reduced-dimensionality dataset through serial k-means clustering. Most predictor groups showed significant association with at least one hydration biomarker: 1) Glycemic Load + Carbohydrates + Sodium, 2) Protein + Fat + Zinc, 3) Magnesium + Calcium, 4) Pinitol, 5) Caffeine, 6) Fiber + Betaine, and 7) Water; potassium + three polyols, and mannitol + sorbitol showed no significant associations with any hydration biomarker. All five hydration biomarkers were associated with at least one nutrient predictor in at least one configuration. We conclude that in a real-life scenario, some nutrients may serve as mediators of body water, and urine-specific hydration biomarkers may be more responsive to nutrient intake than measures derived from plasma or body mass.

2.
Metab Syndr Relat Disord ; 18(4): 176-185, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32119801

RESUMO

Current algorithms for assessing risk of atherosclerotic cardiovascular disease (ASCVD) and, in particular, the reliance on low-density lipoprotein (LDL) cholesterol in conditions where this measurement is discordant with apoB and LDL-particle concentrations fail to identify a sizeable part of the population at high risk for adverse cardiovascular events. This results in missed opportunities for ASCVD prevention, most notably in those with metabolic syndrome, prediabetes, and diabetes. There is substantial evidence that accumulation of ectopic fat and associated metabolic traits are markers for and pathogenic components of high-risk atherosclerosis. Conceptually, the subset of advanced lesions in high-risk atherosclerosis that triggers vascular complications is closely related to a set of coordinated high-risk traits clustering around a distinct metabolic phenotype. A key feature of this phenotype is accumulation of ectopic fat, which, coupled with age-related muscle loss, creates a milieu conducive for the development of ASCVD: atherogenic dyslipidemia, nonresolving inflammation, endothelial dysfunction, hyperinsulinemia, and impaired fibrinolysis. Sustained vascular inflammation, a hallmark of high-risk atherosclerosis, impairs plaque stabilization in this phenotype. This review describes how metabolic and inflammatory processes that are promoted in large measure by ectopic adiposity, as opposed to subcutaneous adipose tissue, relate to the pathogenesis of high-risk atherosclerosis. Clinical biomarkers indicative of these processes provide incremental information to standard risk factor algorithms and advanced lipid testing identifies atherogenic lipoprotein patterns that are below the discrimination level of standard lipid testing. This has the potential to enable improved identification of high-risk patients who are candidates for therapeutic interventions aimed at prevention of ASCVD.

3.
Eur J Prev Cardiol ; 27(4): 394-406, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31408370

RESUMO

Despite major efforts to reduce atherosclerotic cardiovascular disease (ASCVD) burden with conventional risk factor control, significant residual risk remains. Recent evidence on non-traditional determinants of cardiometabolic health has advanced our understanding of lifestyle-disease interactions. Chronic exposure to environmental stressors like poor diet quality, sedentarism, ambient air pollution and noise, sleep deprivation and psychosocial stress affect numerous traditional and non-traditional intermediary pathways related to ASCVD. These include body composition, cardiorespiratory fitness, muscle strength and functionality and the intestinal microbiome, which are increasingly recognized as major determinants of cardiovascular health. Evidence points to partially overlapping mechanisms, including effects on inflammatory and nutrient sensing pathways, endocrine signalling, autonomic function and autophagy. Of particular relevance is the potential of low-risk lifestyle factors to impact on plaque vulnerability through altered adipose tissue and skeletal muscle phenotype and secretome. Collectively, low-risk lifestyle factors cause a set of phenotypic adaptations shifting tissue cross-talk from a proinflammatory milieu conducive for high-risk atherosclerosis to an anti-atherogenic milieu. The ketone body ß-hydroxybutyrate, through inhibition of the NLRP-3 inflammasome, is likely to be an intermediary for many of these observed benefits. Adhering to low-risk lifestyle factors adds to the prognostic value of optimal risk factor management, and benefit occurs even when the impact on conventional risk markers is discouragingly minimal or not present. The aims of this review are (a) to discuss novel lifestyle risk factors and their underlying biochemical principles and (b) to provide new perspectives on potentially more feasible recommendations to improve long-term adherence to low-risk lifestyle factors.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31231311

RESUMO

Purpose: Studies on long-term sustainability of low-carbohydrate approaches to treat diabetes are limited. We previously reported the effectiveness of a novel digitally-monitored continuous care intervention (CCI) including nutritional ketosis in improving weight, glycemic outcomes, lipid, and liver marker changes at 1 year. Here, we assess the effects of the CCI at 2 years. Materials and methods: An open label, non-randomized, controlled study with 262 and 87 participants with T2D were enrolled in the CCI and usual care (UC) groups, respectively. Primary outcomes were retention, glycemic control, and weight changes at 2 years. Secondary outcomes included changes in body composition, liver, cardiovascular, kidney, thyroid and inflammatory markers, diabetes medication use and disease status. Results: Reductions from baseline to 2 years in the CCI group resulting from intent-to-treat analyses included: HbA1c, fasting glucose, fasting insulin, weight, systolic blood pressure, diastolic blood pressure, triglycerides, and liver alanine transaminase, and HDL-C increased. Spine bone mineral density in the CCI group was unchanged. Use of any glycemic control medication (excluding metformin) among CCI participants declined (from 55.7 to 26.8%) including insulin (-62%) and sulfonylureas (-100%). The UC group had no changes in these parameters (except uric acid and anion gap) or diabetes medication use. There was also resolution of diabetes (reversal, 53.5%; remission, 17.6%) in the CCI group but not in UC. All the reported improvements had p < 0.00012. Conclusion: The CCI group sustained long-term beneficial effects on multiple clinical markers of diabetes and cardiometabolic health at 2 years while utilizing less medication. The intervention was also effective in the resolution of diabetes and visceral obesity with no adverse effect on bone health. Clinical Trial Registration: Clinicaltrials.gov NCT02519309.

5.
Sleep Med ; 55: 92-99, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30772699

RESUMO

OBJECTIVE: Sleep disruption is frequently associated with type 2 diabetes (T2D) and hyperglycemia. We recently reported the effectiveness of a continuous care intervention (CCI) emphasizing nutritional ketosis for improving HbA1c, body weight and cardiovascular risk factors in T2D patients. The present study assessed the effect of this CCI approach on sleep quality using a subjective patient-reported sleep questionnaire. METHODS: A non-randomized, controlled longitudinal study; 262 T2D and 116 prediabetes patients enrolled in the CCI and 87 separately recruited T2D patients continued usual care (UC) treatment. Patients completed the Pittsburgh Sleep Quality Index (PSQI) questionnaire. A PSQI score of >5 (scale 0 to 21) was used to identify poor sleepers. RESULTS: Global sleep quality improved in the CCI T2D (p < 0.001) and prediabetes (p < 0.001) patients after one year of intervention. Subjective sleep quality (component 1), sleep disturbance (component 5) and daytime dysfunction (component 7), also showed improvements in the CCI T2D (p < 0.01 for sleep quality and sleep disturbance; and p < 0.001 for daytime dysfunction) and prediabetes patients (p < 0.001 for all three components); compared to the UC T2D group after one year. The proportion of patients with poor sleep quality was significantly reduced after one year of CCI (T2D; from 68.3% at baseline to 56.5% at one year, p = 0.001 and prediabetes; from 77.9% at baseline to 48.7% at one year, p < 0.001). CONCLUSION: This study demonstrates improved sleep quality as assessed by PSQI in patients with T2D and prediabetes undergoing CCI including nutritional ketosis but not in T2D patients receiving UC. The dietary intervention benefited both sleep quality and the severity of T2D symptoms suggesting that nutritional ketosis improves overall health via multiple mechanisms.


Assuntos
Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/diagnóstico , Dieta Cetogênica/métodos , Estado Pré-Diabético/dietoterapia , Estado Pré-Diabético/diagnóstico , Transtornos do Sono-Vigília/dietoterapia , Transtornos do Sono-Vigília/diagnóstico , Adulto , Idoso , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Estado Pré-Diabético/metabolismo , Fatores de Risco , Sono/fisiologia , Transtornos do Sono-Vigília/metabolismo , Adulto Jovem
6.
BMJ Open ; 9(2): e023597, 2019 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-30803948

RESUMO

OBJECTIVE: One year of comprehensive continuous care intervention (CCI) through nutritional ketosis improves glycosylated haemoglobin(HbA1c), body weight and liver enzymes among patients with type 2 diabetes (T2D). Here, we report the effect of the CCI on surrogate scores of non-alcoholic fatty liver disease (NAFLD) and liver fibrosis. METHODS: This was a non-randomised longitudinal study, including adults with T2D who were self-enrolled to the CCI (n=262) or to receive usual care (UC, n=87) during 1 year. An NAFLD liver fat score (N-LFS) >-0.640 defined the presence of fatty liver. An NAFLD fibrosis score (NFS) of >0.675 identified subjects with advanced fibrosis. Changes in N-LFS and NFS at 1 year were the main endpoints. RESULTS: At baseline, NAFLD was present in 95% of patients in the CCI and 90% of patients in the UC. At 1 year, weight loss of ≥5% was achieved in 79% of patients in the CCI versus 19% of patients in UC (p<0.001). N-LFS mean score was reduced in the CCI group (-1.95±0.22, p<0.001), whereas it was not changed in the UC (0.47±0.41, p=0.26) (CCI vs UC, p<0.001). NFS was reduced in the CCI group (-0.65±0.06, p<0.001) compared with UC (0.26±0.11, p=0.02) (p<0.001 between two groups). In the CCI group, the percentage of individuals with a low probability of advanced fibrosis increased from 18% at baseline to 33% at 1 year (p<0.001). CONCLUSIONS: One year of a digitally supported CCI significantly improved surrogates of NAFLD and advanced fibrosis in patients with T2D. TRIAL REGISTRATION NUMBER: NCT02519309; Results.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Cirrose Hepática/sangue , Hepatopatia Gordurosa não Alcoólica/sangue , Biomarcadores/sangue , Diabetes Mellitus Tipo 2/dietoterapia , Dieta Rica em Proteínas e Pobre em Carboidratos , Feminino , Humanos , Cirrose Hepática/diagnóstico , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados não Aleatórios como Assunto , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Índice de Gravidade de Doença , Adulto Jovem
7.
Cardiovasc Diabetol ; 17(1): 56, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29712560

RESUMO

BACKGROUND: Cardiovascular disease (CVD) is a leading cause of death among adults with type 2 diabetes mellitus (T2D). We recently reported that glycemic control in patients with T2D can be significantly improved through a continuous care intervention (CCI) including nutritional ketosis. The purpose of this study was to examine CVD risk factors in this cohort. METHODS: We investigated CVD risk factors in patients with T2D who participated in a 1 year open label, non-randomized, controlled study. The CCI group (n = 262) received treatment from a health coach and medical provider. A usual care (UC) group (n = 87) was independently recruited to track customary T2D progression. Circulating biomarkers of cholesterol metabolism and inflammation, blood pressure (BP), carotid intima media thickness (cIMT), multi-factorial risk scores and medication use were examined. A significance level of P < 0.0019 ensured two-tailed significance at the 5% level when Bonferroni adjusted for multiple comparisons. RESULTS: The CCI group consisted of 262 participants (baseline mean (SD): age 54 (8) year, BMI 40.4 (8.8) kg m-2). Intention-to-treat analysis (% change) revealed the following at 1-year: total LDL-particles (LDL-P) (- 4.9%, P = 0.02), small LDL-P (- 20.8%, P = 1.2 × 10-12), LDL-P size (+ 1.1%, P = 6.0 × 10-10), ApoB (- 1.6%, P = 0.37), ApoA1 (+ 9.8%, P < 10-16), ApoB/ApoA1 ratio (- 9.5%, P = 1.9 × 10-7), triglyceride/HDL-C ratio (- 29.1%, P < 10-16), large VLDL-P (- 38.9%, P = 4.2 × 10-15), and LDL-C (+ 9.9%, P = 4.9 × 10-5). Additional effects were reductions in blood pressure, high sensitivity C-reactive protein, and white blood cell count (all P < 1 × 10-7) while cIMT was unchanged. The 10-year atherosclerotic cardiovascular disease (ASCVD) risk score decreased - 11.9% (P = 4.9 × 10-5). Antihypertensive medication use was discontinued in 11.4% of CCI participants (P = 5.3 × 10-5). The UC group of 87 participants [baseline mean (SD): age 52 (10) year, BMI 36.7 (7.2) kg m-2] showed no significant changes. After adjusting for baseline differences when comparing CCI and UC groups, significant improvements for the CCI group included small LDL-P, ApoA1, triglyceride/HDL-C ratio, HDL-C, hsCRP, and LP-IR score in addition to other biomarkers that were previously reported. The CCI group showed a greater rise in LDL-C. CONCLUSIONS: A continuous care treatment including nutritional ketosis in patients with T2D improved most biomarkers of CVD risk after 1 year. The increase in LDL-cholesterol appeared limited to the large LDL subfraction. LDL particle size increased, total LDL-P and ApoB were unchanged, and inflammation and blood pressure decreased. Trial registration Clinicaltrials.gov: NCT02519309. Registered 10 August 2015.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Prestação Integrada de Cuidados de Saúde , Diabetes Mellitus Tipo 2/dietoterapia , Cetoacidose Diabética/dietoterapia , Dieta com Restrição de Carboidratos , Dieta para Diabéticos , Estado Nutricional , Ácido 3-Hidroxibutírico/sangue , Adulto , Biomarcadores/sangue , Glicemia/metabolismo , Pressão Sanguínea , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/fisiopatologia , Terapia Combinada , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/fisiopatologia , Cetoacidose Diabética/sangue , Cetoacidose Diabética/diagnóstico , Cetoacidose Diabética/fisiopatologia , Dieta com Restrição de Carboidratos/efeitos adversos , Dieta para Diabéticos/efeitos adversos , Feminino , Humanos , Hipoglicemiantes/uso terapêutico , Indiana , Mediadores da Inflamação/sangue , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
9.
Diabetes Ther ; 9(2): 583-612, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29417495

RESUMO

INTRODUCTION: Carbohydrate restriction markedly improves glycemic control in patients with type 2 diabetes (T2D) but necessitates prompt medication changes. Therefore, we assessed the effectiveness and safety of a novel care model providing continuous remote care with medication management based on biometric feedback combined with the metabolic approach of nutritional ketosis for T2D management. METHODS: We conducted an open-label, non-randomized, controlled, before-and-after 1-year study of this continuous care intervention (CCI) and usual care (UC). Primary outcomes were glycosylated hemoglobin (HbA1c), weight, and medication use. Secondary outcomes included fasting serum glucose and insulin, HOMA-IR, blood lipids and lipoproteins, liver and kidney function markers, and high-sensitivity C-reactive protein (hsCRP). RESULTS: 349 adults with T2D enrolled: CCI: n = 262 [mean (SD); 54 (8) years, 116.5 (25.9) kg, 40.4 (8.8) kg m2, 92% obese, 88% prescribed T2D medication]; UC: n = 87 (52 (10) years, 105.6 (22.15) kg, 36.72 (7.26) kg m2, 82% obese, 87% prescribed T2D medication]. 218 participants (83%) remained enrolled in the CCI at 1 year. Intention-to-treat analysis of the CCI (mean ± SE) revealed HbA1c declined from 59.6 ± 1.0 to 45.2 ± 0.8 mmol mol-1 (7.6 ± 0.09% to 6.3 ± 0.07%, P < 1.0 × 10-16), weight declined 13.8 ± 0.71 kg (P < 1.0 × 10-16), and T2D medication prescription other than metformin declined from 56.9 ± 3.1% to 29.7 ± 3.0% (P < 1.0 × 10-16). Insulin therapy was reduced or eliminated in 94% of users; sulfonylureas were entirely eliminated in the CCI. No adverse events were attributed to the CCI. Additional CCI 1-year effects were HOMA-IR - 55% (P = 3.2 × 10-5), hsCRP - 39% (P < 1.0 × 10-16), triglycerides - 24% (P < 1.0 × 10-16), HDL-cholesterol + 18% (P < 1.0 × 10-16), and LDL-cholesterol + 10% (P = 5.1 × 10-5); serum creatinine and liver enzymes (ALT, AST, and ALP) declined (P ≤ 0.0001), and apolipoprotein B was unchanged (P = 0.37). UC participants had no significant changes in biomarkers or T2D medication prescription at 1 year. CONCLUSIONS: These results demonstrate that a novel metabolic and continuous remote care model can support adults with T2D to safely improve HbA1c, weight, and other biomarkers while reducing diabetes medication use. CLINICALTRIALS. GOV IDENTIFIER: NCT02519309. FUNDING: Virta Health Corp.

10.
Ann Nutr Metab ; 70 Suppl 1: 18-22, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28614809

RESUMO

BACKGROUND: Urine osmolality (UOSM) reflects the renal regulation of excess fluid or deficit fluid, and therefore, serves as a marker of hydration status. Little is known about monitoring hydration in pregnant and lactating women despite significant physiological challenges to body water balance during that time. Therefore, we designed a study to assess if urine color (UCOL), an inexpensive and practical method, was a valid means of assessing urine concentration. Twenty-four hour UCOL was significantly correlated with 24 h UOSM in all women: pregnant, lactating, and control (r = 0.61-0.84, all p < 0.001). Utilizing a receiver operating characteristic statistical analysis, we found that 24 h and single sample UCOL had excellent diagnostic accuracy for identifying UOSM ≥500 mOsm·kg-1 in all women (area under the curve = 0.68-0.95, p < 0.001-0.46), and the UCOL that reflected this cut off was ≥4 on the UCOL chart. SUMMARY: Therefore, UCOL is a valid marker of urine concentration and ultimately hydration status in pregnant, lactating, and non-pregnant, non-lactating women. For pregnant, lactating, and control women, the UCOL chart is a valid tool that can be used to monitor urine concentration in a single sample or over the course of the day via a 24 h sample. Key Message: Women who present with a UCOL of 4 or more likely have a UOSM ≥500 mOsm·kg-1. Given the positive health benefits associated with UOSM <500 mOsm·kg-1, women should aim for a 1, 2, or 3 on the UCOL chart. If a UCOL of ≥4 is observed, women should consider increasing fluid consumption to improve hydration status.


Assuntos
Biomarcadores/urina , Aleitamento Materno , Ingestão de Líquidos , Lactação/fisiologia , Urinálise/normas , Adulto , Estudos de Casos e Controles , Cor , Desidratação/prevenção & controle , Desidratação/urina , Feminino , Humanos , Recém-Nascido , Concentração Osmolar , Pigmentação , Gravidez , Complicações na Gravidez/prevenção & controle , Complicações na Gravidez/urina , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Gravidade Específica , Urina/química , Adulto Jovem
11.
JMIR Diabetes ; 2(1): e5, 2017 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30291062

RESUMO

BACKGROUND: Type 2 diabetes (T2D) is typically managed with a reduced fat diet plus glucose-lowering medications, the latter often promoting weight gain. OBJECTIVE: We evaluated whether individuals with T2D could be taught by either on-site group or remote means to sustain adequate carbohydrate restriction to achieve nutritional ketosis as part of a comprehensive intervention, thereby improving glycemic control, decreasing medication use, and allowing clinically relevant weight loss. METHODS: This study was a nonrandomized, parallel arm, outpatient intervention. Adults with T2D (N=262; mean age 54, SD 8, years; mean body mass index 41, SD 8, kg·m-2; 66.8% (175/262) women) were enrolled in an outpatient protocol providing intensive nutrition and behavioral counseling, digital coaching and education platform, and physician-guided medication management. A total of 238 participants completed the first 10 weeks. Body weight, capillary blood glucose, and beta-hydroxybutyrate (BOHB) levels were recorded daily using a mobile interface. Hemoglobin A1c (HbA1c) and related biomarkers of T2D were evaluated at baseline and 10-week follow-up. RESULTS: Baseline HbA1c level was 7.6% (SD 1.5%) and only 52/262 (19.8%) participants had an HbA1c level of <6.5%. After 10 weeks, HbA1c level was reduced by 1.0% (SD 1.1%; 95% CI 0.9% to 1.1%, P<.001), and the percentage of individuals with an HbA1c level of <6.5% increased to 56.1% (147/262). The majority of participants (234/262, 89.3%) were taking at least one diabetes medication at baseline. By 10 weeks, 133/234 (56.8%) individuals had one or more diabetes medications reduced or eliminated. At follow-up, 47.7% of participants (125/262) achieved an HbA1c level of <6.5% while taking metformin only (n=86) or no diabetes medications (n=39). Mean body mass reduction was 7.2% (SD 3.7%; 95% CI 5.8% to 7.7%, P<.001) from baseline (117, SD 26, kg). Mean BOHB over 10 weeks was 0.6 (SD 0.6) mmol·L-1 indicating consistent carbohydrate restriction. Post hoc comparison of the remote versus on-site means of education revealed no effect of delivery method on change in HbA1c (F1,260=1.503, P=.22). CONCLUSIONS: These initial results indicate that an individualized program delivered and supported remotely that incorporates nutritional ketosis can be highly effective in improving glycemic control and weight loss in adults with T2D while significantly decreasing medication use.

12.
Eur J Nutr ; 56(1): 355-362, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26572890

RESUMO

AIM: Urine concentration measured via osmolality (U OSM) and specific gravity (U SG) reflects the adequacy of daily fluid intake, which has important relationships to health in pregnant (PREG) and lactating (LACT) women. Urine color (U COL) may be a practical, surrogate marker for whole-body hydration status. PURPOSE: To determine whether U COL was a valid measure of urine concentration in PREG and LACT, and pair-matched non-pregnant, non-lactating control women (CON). METHODS: Eighteen PREG/LACT (age 31 ± 1 years, pre-pregnancy BMI 24.3 ± 5.9 kg m-2) and eighteen CON (age 29 ± 4 years, BMI 24.1 ± 3.7 kg m-2) collected 24-h and single-urine samples on specified daily voids at five time points (15 ± 2, 26 ± 1, and 37 ± 1 weeks gestation, 3 ± 1 and 9 ± 1 weeks postpartum during lactation; CON visits were separated by similar time intervals) for measurement of 24-h U OSM, U SG, and U COL and single-sample U OSM and U COL. RESULTS: Twenty-four-hour U COL was significantly correlated with 24-h U OSM (r = 0.6085-0.8390, P < 0.0001) and 24-h U SG (r = 0.6213-0.8985, P < 0.0001) in all groups. A 24-h U COL ≥ 4 (AUC = 0.6848-0.9513, P < 0.05) and single-sample U COL ≥ 4 (AUC = 0.9094-0.9216, P < 0.0001) indicated 24-h U OSM ≥ 500 mOsm kg-1 (representing inadequate fluid intake) in PREG, LACT, and CON. CONCLUSIONS: Urine color was a valid marker of urine concentration in all groups. Thus, PREG, LACT, and CON can utilize U COL to monitor their daily fluid balance. Women who present with a U COL ≥ 4 likely have a U OSM ≥ 500 mOsm kg-1 and should increase fluid consumption to improve overall hydration status.


Assuntos
Desidratação/diagnóstico , Desidratação/urina , Lactação , Gravidez , Adulto , Biomarcadores/urina , Índice de Massa Corporal , Estudos de Casos e Controles , Cor , Ingestão de Líquidos , Feminino , Humanos , Concentração Osmolar , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Gravidade Específica , Urinálise , Equilíbrio Hidroeletrolítico
13.
Eur J Nutr ; 56(6): 2161-2170, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27519184

RESUMO

INTRODUCTION: Previous research established significant relationships between total fluid intake (TFI) and urinary biomarkers of the hydration process in free-living males and females; however, the nature of this relationship is not known for pregnant (PREG) and lactating (LACT) women. PURPOSE: To determine the relationship between urinary and hematological hydration biomarkers with TFI in PREG and LACT. METHODS: Eighteen PREG/LACT (age: 31 ± 3 years, pre-pregnancy BMI: 24.26 ± 5.85 kg m-2) collected 24-h urine samples, recorded TFI, and provided a blood sample at 5 time points (15 ± 2, 26 ± 1, 37 ± 1 weeks gestation, 3 ± 1 and 9 ± 1 weeks postpartum during lactation); 18 pair-matched non-pregnant (NP), non-lactating (NL) women (age: 29 ± 4 years, BMI: 24.1 ± 3.7 kg m-2) provided samples at similar time intervals. Twenty-four-hour urine volume (U VOL), osmolality (U OSM), specific gravity (U SG), and color (U COL) were measured. Hematocrit, serum osmolality (S OSM), and serum total protein (S TP) were measured in blood. RESULTS: Significant relationships were present between TFI and urinary biomarkers in all women (P < 0.004); these relationships were not different between PREG and NP, and LACT and NL, except U VOL in PREG (P = 0.0017). No significant relationships between TFI and hematological biomarkers existed (P > 0.05). CONCLUSION: Urinary biomarkers of hydration, but not hematological biomarkers, have a strong relationship with TFI in PREG, LACT, NP, and NL women. These data suggest that urinary biomarkers of hydration reflect TFI during pregnancy and breast-feeding.


Assuntos
Biomarcadores/urina , Ingestão de Líquidos , Lactação , Estado de Hidratação do Organismo , Gravidez , Adulto , Índice de Massa Corporal , Aleitamento Materno , Desidratação/diagnóstico , Desidratação/urina , Feminino , Humanos , Masculino , Equilíbrio Hidroeletrolítico
14.
Int J Exerc Sci ; 9(1): 34-46, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27293505

RESUMO

The purpose of this observational study was to determine the circulating leukocyte subset response to completing the 2013 Hotter'N Hell Hundred recreational 164-km road cycle event in a hot and humid environmental condition. Twenty-eight men and four women were included in this study. Whole blood samples were obtained 1-2 hours before (PRE) and immediately after (POST) the event. Electronic sizing/sorting and cytometry were used to determine complete blood counts (CBC) including neutrophil, monocyte, and lymphocyte subsets. The concentration of circulating total leukocytes (103·µL-1) increased 134% from PRE to POST with the greatest increase in neutrophils (319%, p<0.0001). Circulating monocytes (including macrophages) increased 24% (p=0.004) and circulating lymphocytes including B and T cells increased 53% (p<0.0001). No association was observed between rolling time or relative intensity and leukocyte subset. Completing the Hotter n' Hell Hundred (HHH), a 100 mile recreational cycling race in extreme (hot and humid) environmental conditions, induces a substantial increase in total leukocytes in circulation. The contribution of increases in specific immune cell subsets is not equal, with neutrophils increasing to greater than 4-fold starting values from PRE to POST race. It is likely that exercise in stressful environmental conditions affects the complement of circulating immune cells, although activational state and characterization of specific leukocyte subsets remains unclear. The observed increase in circulating cell sub-populations suggests that the circulating immune surveillance system may be acutely affected by exercise in hot and humid conditions.

15.
Int J Sport Nutr Exerc Metab ; 26(4): 356-62, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26731792

RESUMO

Urine color (Ucol) as a hydration assessment tool provides practicality, ease of use, and correlates moderately to strongly with urine specific gravity (Usg) and urine osmolality (Uosm). Indicative of daily fluid turnover, along with solute and urochrome excretion in 24-hr samples, Ucol may also reflect dietary composition. Thus, the purpose of this investigation was to determine the efficacy of Ucol as a hydration status biomarker after nutritional supplementation with beetroot (880 mg), vitamin C (1000 mg), and riboflavin (200 mg). Twenty males (Mean ± SD; age, 21 ± 2 y; body mass, 82.12 ± 15.58 kg; height, 1.77 ± 0.06 m) consumed a standardized breakfast and collected all urine voids on one control day (CON) and 1 day after consuming a standardized breakfast and a randomized and double-blinded supplement (SUP) over 3 weeks. Participants replicated exercise and diet for one day before CON, and throughout CON and SUP. Ucol, Usg, Uosm, and urine volume were measured in all 24-hr samples, and Ucol and Usg were measured in all single samples. Ucol was a significant predictor of single sample Usg after all supplements (p < .05). Interestingly, 24-hr Ucol was not a significant predictor of 24-h Usg and Uosm after riboflavin supplementation (p = .20, p = .21). Further, there was a significant difference between CON and SUP 24-h Ucol only after riboflavin supplementation (p < .05). In conclusion, this investigation suggests that users of the UCC (urine color chart) should consider riboflavin supplementation when classifying hydration status and use a combination of urinary biomarkers (e.g., Usg and Ucol), both acutely and over 24 hr.


Assuntos
Ácido Ascórbico/administração & dosagem , Suplementos Nutricionais , Riboflavina/administração & dosagem , Equilíbrio Hidroeletrolítico , Atletas , Beta vulgaris/química , Biomarcadores/urina , Índice de Massa Corporal , Peso Corporal , Desjejum , Dieta , Método Duplo-Cego , Exercício Físico , Humanos , Masculino , Concentração Osmolar , Urinálise , Adulto Jovem
16.
Eur J Nutr ; 55(5): 1943-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26286348

RESUMO

PURPOSE: Urine colour (U Col) is simple to measure, differs between low-volume and high-volume drinkers, and is responsive to changes in daily total fluid intake (TFI). However, to date, no study has quantified the relationship between a change in TFI and the resultant change in U Col. This analysis aimed to determine the change in TFI needed to adjust 24-h U Col by 2 shades on an 8-colour scale, and to evaluate whether starting U Col altered the relationship between the change in TFI and change in U Col. METHODS: We performed a pooled analysis on data from 238 healthy American and European adults (50 % male; age, 28 (sd 6) years; BMI 22.9 (sd 2.6) kg/m(2)), and evaluated the change in TFI, urine volume (U Vol), and specific gravity (U SG) associated with a change in U Col of 2 shades. RESULTS: The mean [95 % CI] change in TFI and U Vol associated with a decrease in U Col by 2 shades (lighter) was 1110 [914;1306] and 1011 [851;1172] mL/day, respectively, while increasing U Col by 2 shades (darker) required a reduction in TFI and U Vol of -1114 [-885;-1343] and -977 [-787;-1166] mL/day. The change in U Col was accompanied by changes in U SG (lighter urine: -.008 [-.007;-.010]; darker urine: +.008 [.006;.009]). Starting U Col did not significantly impact the TFI change required to modify U Col by 2 shades. CONCLUSIONS: Our results suggest a quantifiable relationship between a change in daily TFI and the resultant change in U Col, providing individuals with a practical means for evaluating and adjusting hydration behaviours.


Assuntos
Água Potável/administração & dosagem , Água Potável/análise , Ingestão de Líquidos , Urinálise , Adulto , Cor , Desidratação/diagnóstico , Estudos de Avaliação como Assunto , Feminino , Humanos , Estilo de Vida , Masculino , Estudos Retrospectivos , Gravidade Específica , Equilíbrio Hidroeletrolítico , Adulto Jovem
17.
J Sports Sci ; 34(8): 694-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26199143

RESUMO

This study investigated the acute endocrine responses to a 164-km road cycling event in a hot environment. Thirty-four male experienced cyclists (49.1 ± 8.3 years, 86.8 ± 12.5 kg, 178.1 ± 5.1 cm) participating in a 164-km road cycling event were recruited. Blood samples were collected within 0.3-2.0 h before the start (PRE: ~0500-0700 h) and immediately following the ride (POST). Samples were analysed for testosterone, growth hormone (GH), cortisol and interleukin-6 (IL-6). The temperature and humidity during the event were 35.3 ± 4.9°C and 47.2 ± 14.0%, respectively. Based on the finishing time, results for the fastest (FAST, 305 ± 10 min) and the slowest (SLOW, 467 ± 31 min) quartiles were compared. At POST, testosterone concentration was significantly (P < 0.05) lower (PRE, 20.8 ± 8.6; POST, 18.2 ± 6.7 nmol · L(-1)), while GH (PRE, 0.3 ± 0.1; POST, 2.3 ± 0.3 µg · L(-1)), cortisol (PRE, 661 ± 165; POST, 1073 ± 260 nmol · L(-1)) and IL-6 (PRE, 4.0 ± 3.4; POST, 22.4 ± 15.2 pg · mL(-1)) concentrations were significantly higher than those at PRE. At POST, GH and cortisol were significantly higher for the FAST group than for the SLOW group (GH, 3.6 ± 2.0 and 1.0 ± 0.8 µg · L(-1); cortisol, 1187 ± 209 and 867 ± 215 nmol · L(-1)). Participation in an ultra-endurance road cycling event in a hot environment induced significant acute changes in concentrations of circulating hormones, with a greater augmentation of GH and cortisol in those completing the ride fastest.


Assuntos
Ciclismo/fisiologia , Temperatura Alta , Hormônio do Crescimento Humano/sangue , Hidrocortisona/sangue , Interleucina-6/sangue , Testosterona/sangue , Adulto , Humanos , Umidade , Masculino , Pessoa de Meia-Idade , Resistência Física/fisiologia
18.
J Athl Train ; 51(11): 927-935, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28068165

RESUMO

CONTEXT: Cooling devices aim to protect firefighters by attenuating a rise in body temperature. Devices for head cooling (HC) while firefighting and forearm cooling (FC) during rehabilitation (RHB) intervals are commonly marketed, but research regarding their efficacy is limited. OBJECTIVE: To investigate the physiological and perceived effects of HC and FC during firefighting drills and RHB. DESIGN: Randomized controlled clinical trial. SETTING: Firefighter training center. PATIENTS OR OTHER PARTICIPANTS: Twenty-seven male career firefighters (age = 39 ± 7 years; height = 169 ± 7 cm; weight = 95.4 ± 16.8 kg). INTERVENTION(S): Firefighters were randomly assigned to 1 condition: HC (n = 9), in which participants completed drills wearing a cold gel pack inside their helmet; FC (n = 8), in which participants sat on a collapsible chair with water-immersion arm troughs during RHB; or control (n = 10), in which participants used no cooling devices. Firefighters completed four 15-minute drills (D1-D4) wearing full bunker gear and breathing apparatus. Participants had a 15-min RHB after D2 (RHB1) and D4 (RHB2). MAIN OUTCOME MEASURE(S): Change (Δ) in gastrointestinal temperature (TGI), heart rate (HR), physiological strain index, and perceived thermal sensation. RESULTS: The TGI increased similarly in the HC and control groups, respectively (D1: 0.57°C ± 0.41°C, 0.73°C ± 0.30°C; D2: 0.92°C ± 0.28°C, 0.85°C ± 0.27°C; D3: -0.37°C ± 0.34°C, -0.01°C ± 0.72°C; D4: 0.25°C ± 0.42°C, 0.57°C ± 0.26°C; P > .05). The ΔHR, Δ physiological strain index, and Δ thermal sensation were similar between the HC and control groups during drills (P > .05). The FC group demonstrated a decreased TGI compared with the control group after RHB1 (-1.61°C ± 0.35°C versus -0.23°C ± 0.34°C; P < .001) and RHB2 (-1.40°C ± 0.38°C versus -0.38°C ± 0.24°C; P < .001). The physiological strain index score decreased in the FC group compared with the control group after RHB1 (-7.9 ± 1.3 versus -2.6 ± 1.7; P < .001) and RHB2 (-7.9 ± 1.6 versus -3.6 ± 1.1; P < .001), but no differences between groups were demonstrated for ΔHR or Δ thermal sensation (P > .05). CONCLUSIONS: The HC did not attenuate rises in physiological or perceptual variables during firefighting drills. The FC effectively reduced TGI and the physiological strain index score but not HR or thermal sensation during RHB. Clinicians and firefighters should not recommend the use of HC during firefighting but can consider using FC during RHB intervals in the field.


Assuntos
Temperatura Corporal/fisiologia , Temperatura Baixa/efeitos adversos , Bombeiros , Hipotermia/reabilitação , Adulto , Antebraço , Cabeça , Frequência Cardíaca/fisiologia , Humanos , Hipotermia/fisiopatologia , Masculino , Percepção , Adulto Jovem
19.
Nutrition ; 32(1): 79-82, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26440862

RESUMO

OBJECTIVES: The physiological regulation of total body water and fluid concentrations is complex and dynamic. The human daily water requirement varies because of differences in body size, dietary solute load, exercise, and activities. Although chronically concentrated urine increases the risk of renal diseases, an empirical method to determine inadequate daily water consumption has not been described for any demographic group; instead, statistical analyses are applied to estimate nutritional guidelines (i.e., adequate intake). This investigation describes a novel empirical method to determine the 24-h total fluid intake (TFI; TFI = water + beverages + moisture in food) and 24-h urine volume, which correspond to inadequate 24-h water intake (defined as urine osmolality of 800 mOsm/kg; U800). METHODS: Healthy young women (mean ± standard deviation; age, 20 ± 2 y, mass, 60.8 ± 11.7 kg; n = 28) were observed for 7 consecutive days. A 24-h urine sample was analyzed for volume and osmolality. Diet records were analyzed to determine 24-h TFI. RESULTS: For these 28 healthy young women, the U800 corresponded to a TFI ≥2.4 L/d (≥39 mL/kg/d) and a urine volume ≥1.3 L/d. CONCLUSIONS: The U800 method could be employed to empirically determine 24-h TFI and 24-h urine volumes that correspond to inadequate water intake in diverse demographic groups, residents of specific geographic regions, and individuals who consume specialized diets or experience large daily water turnover. Because laboratory expertise and instrumentation are required, this technique provides greatest value in research and clinical settings.


Assuntos
Água Corporal/fisiologia , Desidratação/urina , Dieta , Ingestão de Líquidos , Comportamento Alimentar , Equilíbrio Hidroeletrolítico , Água , Adolescente , Biomarcadores/urina , Registros de Dieta , Feminino , Alimentos , Humanos , Concentração Osmolar , Valores de Referência , Adulto Jovem
20.
Int J Sport Nutr Exerc Metab ; 26(2): 161-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26479401

RESUMO

This field investigation assessed differences (e.g., drinking behavior, hydration status, perceptual ratings) between female and male endurance cyclists who completed a 164-km event in a hot environment (35 °C mean dry bulb) to inform rehydration recommendations for athletes. Three years of data were pooled to create 2 groups of cyclists: women (n = 15) and men (n = 88). Women were significantly smaller (p < .001) than men in height (166 ± 5 vs. 179 ± 7 cm), body mass (64.6 ± 7.3 vs. 86.4 ± 12.3 kg), and body mass index (BMI; 23.3 ± 1.8 vs. 26.9 ± 3.4) and had lower preevent urinary indices of hydration status, but were similar to men in age (43 ± 7 years vs. 44 ± 9 years) and exercise time (7.77 ± 1.24 hr vs. 7.23 ± 1.75 hr). During the 164-km ride, women lost less body mass (-0.7 ± 1.0 vs. -1.7 ± 1.5 kg; -1.1 ± 1.6% vs. -1.9 ± 1.8% of body weight; p < .005) and consumed less fluid than men (4.80 ± 1.28 L vs. 5.59 ± 2.13 L; p < .005). Women consumed a similar volume of fluid as men, relative to body mass (milliliters/kilogram). To control for performance and anthropomorphic characteristics, 15 women were pair-matched with 15 men on the basis of exercise time on the course and BMI; urine-specific gravity, urine color, and body mass change (kilograms and percentage) were different (p < .05) in 4 of 6 comparisons. No gender differences were observed for ratings of thirst, thermal sensation, or perceived exertion. In conclusion, differences in relative fluid volume consumed and hydration indices suggest that professional sports medicine organizations should consider gender and individualized drinking plans when formulating pronouncements regarding rehydration during exercise.


Assuntos
Ciclismo/fisiologia , Ingestão de Líquidos , Hidratação , Sede , Adulto , Atletas , Feminino , Temperatura Alta , Humanos , Masculino , Pessoa de Meia-Idade , Resistência Física , Gravidade Específica , Urinálise
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