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Background: Preexercise food intake enhances exercise performance due, in part, to the provision of exogenous carbohydrate. Food intake also suppresses hunger, but the specific influence of hunger on exercise performance has not been investigated. This study aimed to manipulate hunger by altering preexercise meal viscosity to examine whether hunger influences performance. Methods: Sixteen resistance-trained males completed 2 experimental trials ingesting either high viscosity semisolid (SEM) and low viscosity liquid (LIQ) carbohydrate-containing meals 2 hours before performing 4 sets of back squat (85 [22] kg) and bench press (68 [13] kg) to failure at 90% 10-repetition maximum. Subjective hunger/fullness as well as plasma concentrations of glucose, insulin, ghrelin, and peptide tyrosine–tyrosine were measured before and periodically after the meal. Repetitions completed in sets were used to determine exercise performance. Results: Hunger was lower, and fullness was greater during SEM compared with LIQ immediately before and during exercise (P <.05). Total repetitions completed for back squat were approximately 10% greater in SEM (SEM 57 [9]; LIQ 51 [7] repetitions; P =.001) with no difference in bench press repetitions (SEM 48 [11]; LIQ 48 [10] repetitions; P =.621). Postprandial glucose concentrations were greater during LIQ (12% increase in peak glucose) but were similar throughout exercise. Conclusion: This study demonstrates that exercise performance in back squat was increased in the SEM trial concomitant to a reduction in hunger. Therefore, this study provides novel data that suggest that exercise performance might be influenced by hunger, at least for resistance exercise. [ABSTRACT FROM AUTHOR]

Background: Scintigraphy is used for overall assessment of gastric emptying. Adherence to an international consensus protocol is recommended to ensure quality; however, this has not been widely adopted because preparation of the "egg‐beater" meal is inconvenient in clinical practice. In this report, we audit the tolerability and the results of gastric emptying scintigraphy with the 400 ml Tc‐99 m‐labeled liquid nutrient Nottingham Test Meal (NTM). Methods: Results from 330 consecutive adult, non‐diabetic patients with dyspeptic symptoms referred for gastric scintigraphy were analyzed. Gastric half‐emptying time (T50) and validated measurements of early‐ and late‐phase gastric emptying were acquired. Postprandial sensations of fullness, bloating, heartburn, nausea, and epigastric pain were recorded using 100 mm visual analog scales (VAS) before and 0, 30, and 90 min after NTM ingestion. Results were compared with those previously obtained in healthy subjects. Key Results: Almost all (98%) of the patients were able to consume the 400 ml NTM. Considering early‐ and late‐phase gastric emptying, frequently observed patterns included normal early‐ with slow late‐phase (25%) and fast early‐ with slow late‐phase emptying (27%). Abnormal score of fullness and/ or dyspeptic symptoms were observed in 88% of dyspeptic patients. Abnormal fullness at T0 (after completed drink ingestion) was associated with slow late phase of gastric emptying, especially in women. Conclusions: Gastric scintigraphy with the NTM is simple to perform and well tolerated. Whether the identified abnormal gastric emptying patterns could predict different treatment outcome in patients with functional dyspepsia is the subject of ongoing prospective studies. [ABSTRACT FROM AUTHOR]

Smoothies are popular breakfast foods. This study examined the effect of consuming Cereal & Milk (CM) or a nutritionally-comparable Fruit Smoothie (FS) for breakfast on daily energy intake (EI) in free-living adults and the extent to which individuals compensated for calories ingested in a High Energy Fruit Smoothie (HE). Ten participants (28.4 ± 2.2y; 23.3 ± 1.0 kg·m -2, Mean ± SEM) attended the laboratory on 3 consecutive days per week for 3 weeks. Each week, they received a CM, FS or HE breakfast, then recorded all food/beverages consumed across the remainder of the day. The CM and FS were energy-matched to participants' usual breakfast (1675 ± 283 kJ), while the HE contained an additional 100 kJ·kg-1 of maltodextrin (3019 ± 335 kJ). Mean 3-day EI was similar on CM and FS (7894 ± 547 vs. 7570 ± 463 kJ, p > .05), but elevated on HE (8861 ± 726 kJ, p =  .012). Thus, individuals who substitute CM for a FS breakfast should be mindful that energy-dense beverages may result in increased daily EI. [ABSTRACT FROM AUTHOR]

Patients with functional dyspepsia frequently show delayed gastric emptying, and dietary advice is frequently given for its improvement. If meal temperature influences gastric emptying, advice regarding the meal temperature may become a possible component of dietary therapy. However, little information exists concerning the thermal effect of meals on gastric emptying. The aim of this study was to determine the thermal effect of liquid and solid meals on gastric emptying. The gastric emptying of liquid and solid test meals was examined in healthy volunteers (liquid, n = 25, mean age = 35.7 ± 9.6 years, male-to-female ratio = 22:3; solid, n = 25, mean age = 35.2 ± 8.8 years, male-to-female ratio = 20:5). Gastric emptying after the ingestion of liquid or solid meals at three different temperatures (4, 37, and 60°C) was investigated with the [13C]-labeled acetate breath test. The lag phase time ( Tmax-calc) and the half-emptying time ( T1/2) were calculated from the 13CO2 breath excretion curve as indices of gastric emptying. The values of Tmax-calc at 60°C with both the liquid and solid meals were significantly smaller than those at 37°C ( P < 0.05). However, there was no difference in the T1/2 values. In the analysis of the percent excretion of 13CO2 in 1 h (% dose/h) data with the liquid meal test in the earlier phase within 30 min, significantly larger values were found at 60°C than at the other temperatures. These findings suggest that a hot meal significantly accelerates gastric emptying. Meal temperature may be considered as a component of dietary therapy for patients with functional dyspepsia. [ABSTRACT FROM AUTHOR]

Intestinal intubation studies have demonstrated that lipids induce satiety, but the contribution of lipid processing by the stomach on satiety remains poorly understood. In this explorative, randomized, placebo-controlled, crossover study we tested whether delayed lipid absorption, increased cholecystokinin (CCK), decelerated gastric emptying (GE), and increased satiety can be achieved by controlling lipid distribution in the stomach. Six healthy men were intubated nasogastrically. Two treatments were performed and repeated in duplicate. In the oil-on-top treatment (UT), subjects received a fat-free liquid meal (LM, 325 ml, 145 kcal) followed by intragastric infusion of 4 g of high-oleic-acid rapeseed oil (4.6 ml, 36 kcal) labeled with 77 mg glyceryl-[13C]trioleate. In the emulsion treatment (EM, control), 4 g of labeled rapeseed oil was incorporated into the LM (325 ml, 181 kcal); 4.6 ml of saline was infused as a control. In UT and EM a second LM was consumed at time t = 270 min. Plasma 3C-C18:1, CCK and satiety were measured over 480 min. GE was determined by the paracetamol absorption test. UT delayed oleic acid absorption shown by an increased lag time of absorption (EM: 37 ± 7 min; UT: 75 ± 10 min; P < 0.01) and time at maximum concentration (EM: 162 ± 18 min; UT: 280 ± 33 min; P = 0.01). UT released more CCK than EM (tP = 0.03), including increased CCK after the second meal. UT accelerated initial GE until 30 min postprandial. UT showed a tendency (P = 0.06) to suppress hunger and increase satiety and fullness 120-270 min postprandially. The results demonstrate that low amounts of lipids, when separated from the aqueous phase of a meal, delay lipid absorption and increase CCK. An escalating-dose study should determine whether this could have implications for the development of weight-control foods. [ABSTRACT FROM AUTHOR]

Chronic glycaemic control, in particular, the control of postprandial hyperglycaemia, is essential for preventing the development of diabetic complications. We therefore evaluated the chronic treatment effect of a new antidiabetic agent, JTT-608 [trans-4-(methylcyclohexyl)-4-oxobutyric acid], in neonatally streptozotocin-treated rats. The rats were maintained with liquid meal three times a day and treated orally with JTT-608 10 min before each meal for 12 weeks. Haemoglobin A1C (HbA1C) and fasting blood glucose levels were measured at 4-week intervals, and effects of JTT-608 on pancreatic function and diabetic complications were examined after dosing period. The postprandial hyperglycaemia was suppressed by JTT-608 administration, and both HbA1C levels and fasting blood glucose levels were reduced during the experimental period. After the treatment period of 12 weeks, JTT-608 further improved the early insulin secretion and the impaired glucose tolerance after meal loading in the diabetic rats. Also, pathological examination revealed that JTT-608 reduced the incidence of the decrease in immunoreactivity of insulin. In examination of other diabetic complications, JTT-608 ameliorated the reduced motor nerve conduction velocities observed in diabetic rats and inhibited the incidence of cataracts with diabetes. We conclude that a newly developed antidiabetic agent, JTT-608, improves the pancreatic function and prevents the development of diabetic complications by inhibition of daily postprandial hyperglycaemia and could be useful for the treatment of diabetic subjects with impaired insulin secretion. [ABSTRACT FROM AUTHOR]

Summary. Background:. The influence of protein fractionation on gastric emptying and rate of appearance of their constituent amino acids in peripheral blood remains unknown. Aim of the study:. To examine the influence of the degree of protein fractionation on gastric emptying, gastric secretion, amino acid absorption and enterogastrone response, after the intragastric administration of complete cow milk proteins or their respective peptide hydrolysates in man. Methods:. Six healthy males were randomized to receive one of the following four solutions: whey whole protein (W), casein whole protein (C), whey peptide hydrolysate (WHY) or casein hydrolysate (CAHY). All solutions were matched for volume (600 mL), nitrogen content (9.3 g/L), energy density (1069–1092 kJ/L), osmolality (288–306 mosmol/kg), pH (6.9–7.0) and temperature (37 °C). Results:. Solutions were emptied at similar rates, with mean half-times of (mean ± SEM) 21.4 ± 1.3, 19.3 ± 2.2, 18.0 ± 2.5 and 19.4 ± 2.8 min, for the WHY, CAHY, C and W, respectively. The rates of intestinal absorption of water and amino acids were similar with the exception of the casein protein solution, for which the speed of intestinal amino acid absorption was slower (p < 0.05). The peptide hydrolysates elicited about 50% more gastric secretion than the whole protein solutions (p < 0.05),which was accompanied by higher glucosedependent insulinotropic polipeptide (GIP) plasma levels during the first 20 min of the gastric emptying process. Similar glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) plasma responses were elicited by the four solutions. Conclusions:. The rate of gastric emptying and the plasma GLP-1 and PYY responses to feeding with cow milk protein solutions in humans are independent of the degree of protein fractionation and are not altered by small differences in the amino acid composition or protein solubility. In contrast, the GIP response is accentuated when milk proteins are delivered as peptide hydrolysates. [ABSTRACT FROM AUTHOR]

Purpose. Monitoring the distribution of drugs or drug delivery systems in the human gastrointestinal tract is an important prerequisite for the design of orally administered drugs. We investigated the intragastric distribution of a colloidal drug delivery system (liposomes containing the contrast agent Gd-DOTA) by magnetic resonance imaging. Methods. Following ingestion of a liquid or a solid meal, gastric distribution of liposomes released from a capsule and the fat component of the solid meal were tracked in 7 healthy subjects for 90 min. Liposomes were identified in gastric content by the increased signal intensity provided by the encapsulated Gd-DOTA. Results. With the liquid meal, liposomes initially formed a layer on the surface before distributing in 86 ± 2% of gastric content (maximum distribution volume) within 42 ± 6 min. With the solid meal, maximum distribution (7 ± 1%, reached within 24 ± 6 min) was confined to a small volume in the fundus without forming a layer, suggesting that distribution was related to the accessible liquid compartment. Fat distribution was inhomogeneous and concentrated in the fundus. Conclusions. Intragastric distribution of a colloidal drug carrier model, such as Gd-DOTA-filled liposomes, varies between meals of different composition. These differences can be monitored in three dimensions in humans by MRI. [ABSTRACT FROM AUTHOR]