Bioavailability of orange juice (poly)phenols: the impact of short-term cessation of training by male endurance athletes

Background: Physical exercise has been reported to increase the bioavailability of citrus flavanones. Objective: To investigate the bioavailability of orange juice (OJ) (poly)phenols in endurance-trained men before and after cessation of training for 7 days. Design: Ten fit endurance-trained males, with a maximal oxygen consumption of 58.2 ± 5.3 mL/kg/min, followed a low (poly)phenol diet for 2 d before drinking 500 mL of OJ, containing 398 µmol of (poly)phenols of which 330 µmol were flavanones. After the volunteers stopped training for 7 days the feeding study was repeated. Urine samples were collected 12 h pre- and 24 h post-OJ orange consumption. Bioavailability was assessed by the quantitative analysis of urinary flavanone metabolites and (poly)phenol catabolites using HPLC-HR-MS. Results: While training, 0-24 h urinary excretion of flavanone metabolites, mainly hesperetin-3-O-glucuronide, hesperetin-3´-sulfate, naringenin-4´-O-glucuronide, naringenin-7-O-glucuronide, was equivalent to 4.2% of OJ flavanone intake. This increased significantly to 5.2% when OJ was consumed after the volunteers stopped training for 7 days. Overall, this trend, although not significant, was also observed with OJ-derived colonic catabolites which after supplementation in the trained state were excreted in amounts equivalent to 51% of intake compared to 59% after cessation of training. However, urinary excretion of three colonic catabolites of bacterial origin, most notably, 3-(3´-hydroxy-4´-methoxyphenyl)hydracrylic acid, did increase significantly when OJ was consumed post- compared to pre-cessation of training. Data were also obtained on inter-individual variations in flavanone bioavailability. Conclusion: A 7-day cessation of endurance training enhanced, rather than reduced, the bioavailability of OJ flavanones. The biological significance of these differences and, whether or not they extend to the bioavailability of other dietary (poly)phenols, remains to be determined. Hesperetin-3´-O-glucuronide and the colonic microbiota-derived catabolite 3-(3´-hydroxy-4´-methoxyphenyl)hydracrylic acid are key biomarkers of the consumption of hesperetin-O-glycoside-containing OJ and other citrus products

Effects of glycerol and creatine hyperhydration on doping-relevant blood parameters

Glycerol is prohibited as an ergogenic aid by the World Anti-Doping Agency (WADA) due to the potential for its plasma expansion properties to have masking effects. However, the scientific basis of the inclusion of Gly as a “masking agent” remains inconclusive. The purpose of this study was to determine the effects of a hyperhydrating supplement containing Gly on doping-relevant blood parameters. Nine trained males ingested a hyperhydrating mixture twice per day for 7 days containing 1.0 g•kg<sup>−1</sup> body mass (BM) of Gly, 10.0 g of creatine and 75.0 g of glucose. Blood samples were collected and total hemoglobin (Hb) mass determined using the optimized carbon monoxide (CO) rebreathing method pre- and post-supplementation. BM and total body water (TBW) increased significantly following supplementation by 1.1 ± 1.2 and 1.0 ± 1.2 L (BM, P < 0.01; TBW, P < 0.01), respectively. This hyperhydration did not significantly alter plasma volume or any of the doping-relevant blood parameters (e.g., hematocrit, Hb, reticulocytes and total Hb-mass) even when Gly was clearly detectable in urine samples. In conclusion, this study shows that supplementation with hyperhydrating solution containing Gly for 7 days does not significantly alter doping-relevant blood parameters

Identification of plasma and urinary metabolites and catabolites derived from orange juice (poly)phenols: analysis by high-performance liquid chromatography–high-resolution mass spectrometry

Orange juice is a rich source of (poly)phenols, in particular, the flavanones hesperetin-7-O-rutinoside and naringenin-7-O-rutinoside. Following the acute consumption of 500 mL of orange juice containing 398 μmol of (poly)phenols by 12 volunteers, 0–24 h plasma and urine samples were analyzed by targeted high-performance liquid chromatography–high-resolution mass spectrometry in order to identify flavanone metabolites and phenolic acid and aromatic catabolites. A total of 19 flavanone metabolites—comprising di-O-glucuronide, O-glucuronide, O-glucuronyl-sulfate, and sulfate derivatives of hesperetin, naringenin, and eriodictyol—and 65 microbial-derived phenolic catabolites, such as phenylpropanoid, phenylpropionic, phenylacetic, benzoic, and hydroxycarboxylic acids and benzenetriol and benzoylglycine derivatives, including free phenolics and phase II sulfate, glucuronide, and methyl metabolites, were identified or partially identified in plasma and/or urine samples. The data obtained provide a detailed evaluation of the fate of orange juice (poly)phenols as they pass through the gastrointestinal tract and are absorbed into the circulatory system prior to renal excretion. Potential pathways for these conversions are proposed

Moderate intensity exercise training combined with inulin-propionate ester supplementation increases whole body resting fat oxidation in overweight women

Background: Our previous work has shown that oral supplementation with inulin propionate ester (IPE) reduces intra-abdominal fat and prevents weight gain and that oral propionate intake enhances resting fat oxidation. The effects of IPE combined with exercise training on energy substrate utilisation are unknown. The aim of this study was to investigate the impact of 4-weeks IPE supplementation, in combination with a moderate intensity exercise training programme, on whole body fat oxidation and on plasma GLP-1 and PYY. Methods: Twenty overweight healthy women participated in randomised parallel study and underwent 4 weeks of supervised exercise training either with IPE (EX/IPE group) or Placebo (EX/Placebo group) supplementation. Before and after the intervention participants conducted an experimental trial, which involved collection of expired gas and blood samples in the fasted state and during 7 h of the postprandial state. Results: Within groups, the EX/IPE group significantly enhanced the amount of fat (Pre, 24.1 ± 1.2 g; Post, 35.9 ± 4.0 g, P < .05) oxidised and reduced CHO (Pre, 77.8 ± 6.0 g; Post, 57.8 ± 7.7 g, P < .05) oxidised, reduced body weight (Pre, 77.3 ± 4.2 kg; Post, 76.6 ± 4.1 kg, P < .05) and body fat mass (Pre, 37.7 ± 1.9%; Post, 36.9 ± 1.9%, P < .05). In EX/Placebo group, changes in amount of fat (Pre, 36.8 ± 3.9 g; Post, 37.0 ± 4.0 g) and CHO (Pre, 62.7 ± 6.5 g; Post, 61.5 ± 7.4 g) oxidised, body weight (Pre, 84.2 ± 4.3 kg; Post, 83.6 ± 4.3 kg) and body fat mass (Pre, 40.1 ± 1.9%; Post, 38.7 ± 1.5%) were not significant (P > .05). Comparing between groups, changes in the amount of fat oxidised were significantly (P < .05) different and a trend for difference was observed for amount of CHO oxidised (P = .06) and RER (P = .06). The interventions had no impact on fasting or postprandial plasma concentrations of GLP-1 and PYY. Conclusion: Moderate intensity exercise training programmes when combined with daily oral IPE supplementation may help overweight women to achieve increase in fat oxidation. The study was registered at clinicaltrials.gov as NCT04016350

Creatine/Glycerol and Creatine/Glycerol/Alpha- lipoic acid supplements: impact on hyperhydration, thermoregulatory and cardiovascular responses during exercise in the heat and cardiometabolic risk factors

The use of solutions containing creatine and glycerol (Cr/Gly) has become popular amongst athletes as a means of hyperhydrating prior to exercise in the heat, since achieving an optimal hydration status appears to be a critical factor for temperature and cardiovascular regulation during exercise in the heat. Hyperhydration has previously been achieved by means of a pre-exercise water loading strategy with the use of hydrating agents (i.e., Cr and Gly) in combination. Certain problems are related to this hyperhydration strategy and are investigated in this thesis. Firstly, the use of Gly has been prohibited and added to the WADA banned list due to the potential of Gly plasma expansion properties, to mask the use of doping substances such as erythropoietin stimulants. However, the scientific basis of the inclusion of Gly as a “masking agent” remains inconclusive. Secondly, the addition of high CHO amounts to the Cr/Gly strategy is central to successful Cr uptake and subsequent hyperhydration. Thirdly, high CHO intake has been linked to high plasma TAG in the athletic population and partial replacement of CHO with insulinotropic agents, such as alpha lipoic acid (Ala), a natural antioxidant and co-factor in the pyruvate dehydrogenase complex, has been shown to enhance Cr uptake under conditions of reduced CHO. On a separate note, Cr and Ala have been found to individually improve Glu tolerance and lipid markers in sedentary individuals while the combined effects of Cr/Ala supplementation on Glu tolerance and lipid markers of sedentary individuals have not been investigated. The aim of chapter 3 was to determine the effects of a hyperhydrating supplement containing 1.0 g/kg of BM of Gly, 10.0 g of Cr and 75.0 g of Gluon on doping-relevant blood parameters. This hyperhydration did not significantly alter PV or any of the doping-relevant blood parameters (e.g., Hct, [Hb], Ret (%) and tHb-mass). Due to the fact that most athletes, in situations where they may be subject to testing by WADA, may choose rapid hyperhydration protocols, the effects of a shorter supplementation 2 protocol on doping related blood parameters, was investigated in chapter 3. For this purpose, a separate cohort of participants consumed the Gly/Cr/Glu supplement over the course of one day. Despite a significant increase in BM over the course of supplementation lasting 8 hours, PV changes and the blood-relevant doping markers of interest were not significantly affected, even when urinary [Gly] was clearly above the urinary [Gly] observed following typical dietary Gly intake. In conclusion, this study showed that supplementation with a hyperhydrating solution containing Gly for 7 days or a short supplementation protocol lasting one day did not significantly alter doping- relevant blood parameters. The aim of chapter 4 was to determine whether Cr/Gly-induced thermoregulatory and cardiovascular responses are maintained when part of the Glu in the Cr/Gly supplement is replaced with the insulintropic agent Ala. Median and range values of TBW increased significantly by 2.1 (1.3-3.3) L and 1.8 (0.2-4.6) L in the Cr/Gly/Glu and Cr/Gly/Glu/Ala groups, respectively (P=0.03). During constant load exercise, HR and Tcore were significantly lower post-supplementation: HR was reduced on average by 3.3±2.1 beats/min and by 4.8±3.3 beats/minute (mean±S.D.) and Tcore by 0.2±0.1 (mean±S.D.) in the Cr/Gly/Glu and Cr/Gly/Glu/Ala groups, respectively. The reduction in HR and Tcore was not significantly different between the supplementation groups. In comparison to the established hyperhydrating Cr/Gly/Glu supplement, a supplement containing Cr/Gly/Ala and decreased amount of Glu provides equal improvements in thermoregulatory and cardiovascular responses during exercise in the heat. The aim of chapter 5 was to determine whether acutely increasing dietary CHO intake prior to endurance events, through the intake of hyperhydrating Cr/Gly solution enriched with Glu, leads to changes in plasma lipids of endurance trained cyclists and whether replacing part of the Glu within this supplement with an insulin potentiating agent, such as Ala, attenuates these changes. Fasting concentration of TAG increased significantly 3 (P<0.01) after supplementation with Cr/Gly/Glu (Pre, 0.9±0.2 mmol/L; Post, 1.3±0.4 mmol/L) and Cr/Gly/Glu/Ala (Pre, 0.8±0.2 mmol/L; Post 1.2±0.5 mmol/L) but the increase in plasma TAG concentration was not significantly different between the two groups. Supplementation had no effect on fasting concentration of total-, HDL-, and LDL- cholesterol and insulin resistance. The acute increase in dietary CHO intake during the 7 days of supplementation with Cr/Gly/Glu induces an increase in plasma TAG concentration that is not attenuated by partial replacement of CHO with Ala. The aim of chapter 6 was to determine whether Cr supplementation, in the absence of exercise would lead to improvements in Glu tolerance in healthy overweight sedentary males and if Cr supplementation combined with Ala, would improve Glu tolerance and plasma lipids in healthy overweight sedentary males. The purpose of this pilot study was to determine the efficacy of Cr and Cr/Ala combined supplementations in improving Glu tolerance, insulin sensitivity and lipid profile of healthy overweight sedentary males. A four-week supplementation with Cr improved Glu tolerance while supplementation with Cr/Ala failed to have such an effect. Nevertheless, supplementation with Cr/Ala for 4 weeks decreased LDL-cholesterol significantly. None of the other blood markers were significantly different following 4 weeks of supplementation with Cr or Cr/Ala. This study found that Cr improved Glu tolerance without any changes in insulin sensitivity or lipid profile of healthy overweight sedentary males, in the absence of exercise. Moreover, the addition of Ala to Cr, had no added effect on Glu uptake, insulin sensitivity or plasma lipids apart from LDL-cholesterol. However, a randomised control trial with a higher sample size, recruiting both experimental, and control groups should be carried out to confirm these findings

Effects of Glycerol and Creatine Hyperhydration on Doping-Relevant Blood Parameters

Glycerol is prohibited as an ergogenic aid by the World Anti-Doping Agency (WADA) due to the potential for its plasma expansion properties to have masking effects. However, the scientific basis of the inclusion of Gly as a “masking agent” remains inconclusive. The purpose of this study was to determine the effects of a hyperhydrating supplement containing Gly on doping-relevant blood parameters. Nine trained males ingested a hyperhydrating mixture twice per day for 7 days containing 1.0 g•kg−1 body mass (BM) of Gly, 10.0 g of creatine and 75.0 g of glucose. Blood samples were collected and total hemoglobin (Hb) mass determined using the optimized carbon monoxide (CO) rebreathing method pre- and post-supplementation. BM and total body water (TBW) increased significantly following supplementation by 1.1 ± 1.2 and 1.0 ± 1.2 L (BM, P < 0.01; TBW, P < 0.01), respectively. This hyperhydration did not significantly alter plasma volume or any of the doping-relevant blood parameters (e.g., hematocrit, Hb, reticulocytes and total Hb-mass) even when Gly was clearly detectable in urine samples. In conclusion, this study shows that supplementation with hyperhydrating solution containing Gly for 7 days does not significantly alter doping-relevant blood parameters

The Effects Of Acute Increase In Carbohydrate Intake On Plasma Lipids In Endurance-Trained Males

No abstract available

The Effects of Hyperhydrating Supplements Containing Creatine and Glucose on Plasma Lipids and Insulin Sensitivity in Endurance-Trained Athletes

The addition of carbohydrate (CHO) in the form of simple sugars to creatine (Cr) supplements is central. The study aimed to determine whether ingestion of glucose (Glu) simultaneously with Cr and glycerol (Cr/Gly) supplement is detrimental to plasma lipids of endurance-trained individuals and find out whether modification arising can be attenuated by replacing part of the Glu with alpha lipoic acid (Ala). Twenty-two endurance-trained cyclists were randomized to receive Cr/Gly/Glu (11.4 g Cr-H2O, 1 g Gly/kg BM, and 150 g Glu) or Cr/Gly/Glu/Ala (11.4 g Cr-H2O, 1 g Gly/kg BM, 100 g Glu, and 1 g Ala) for 7 days. Fasting concentration of TAG increased significantly (P < 0.01) after supplementation with Cr/Gly/Glu (before: 0.9 ± 0.2 mmol/L; after: 1.3 ± 0.4 mmol/L) and Cr/Gly/Glu/Ala (before: 0.8 ± 0.2 mmol/L; after: 1.2 ± 0.5 mmol/L) but changes were not different between the groups. Supplementation significantly (P < 0.05) increased the TAG to HDL-cholesterol ratio but had no effect on fasting concentration of total, HDL-, and LDL-cholesterol and insulin resistance. Thus, addition of Glu to Cr containing supplements enhances plasma TAG concentration and the TAG to HDL-cholesterol ratio and this enhancement cannot be attenuated by partial replacement of Glu with Ala

Plasma pharmacokinetics of (poly)phenol metabolites and catabolites after ingestion of orange juice by endurance trained men

The health benefits of orange juice (OJ) consumption are attributed in part to the circulating flavanone phase II metabolites and their microbial-derived ring fission phenolic catabolites. The present study investigated these compounds in the bloodstream after acute intake of 500 mL of OJ. Plasma samples obtained at 0, 1, 2, 3, 4, 5, 6, 7, 8 and 24 h after OJ intake were analysed by HPLC-HR-MS. Eleven flavanone metabolites and 36 phenolic catabolites were identified and quantified in plasma. The main metabolites were hesperetin-3′-sulfate with a peak plasma concentration (Cmax) of 80 nmol/L, followed by hesperetin-7-glucuronide (Cmax 24 nmol/L), hesperetin-3′-glucuronide (Cmax 18 nmol/L) and naringenin-7-glucuronide (Cmax 21 nmol/L). Among the main phenolic catabolites to increase in plasma after OJ consumption were 3′-methoxycinnamic acid-4′-sulfate (Cmax 19 nmol/L), 3-hydroxy-3-(3′-hydroxy-4′-methoxyphenyl)propanoic acid (Cmax 20 nmol/L), 3-(3′-hydroxy-4′-methoxyphenyl)propanoic acid (Cmax 19 nmol/L), 3-(4′-hydroxyphenyl)propanoic acid (Cmax 25 nmol/L), and 3-(phenyl)propanoic acid (Cmax 19 nmol/L), as well as substantial amounts of phenylacetic and hippuric acids. The comprehensive plasma pharmacokinetic profiles that were obtained are of value to the design of future ex vivo cell studies, aimed at elucidating the mechanisms underlying the potential health benefits of OJ consumption