The acute effect of fasted exercise on energy intake, energy expenditure, subjective hunger and gastrointestinal hormone release compared to fed exercise in healthy individuals: a systematic review and network meta-analysis.

Objective: To determine the acute effect of fasted and fed exercise on energy intake, energy expenditure, subjective hunger and gastrointestinal hormone release.

Methods: CENTRAL, Embase, MEDLINE, PsycInfo, PubMed, Scopus and Web of Science databases were searched to identify randomised, crossover studies in healthy individuals that compared the following interventions: (i) fasted exercise with a standardised post-exercise meal [FastEx + Meal], (ii) fasted exercise without a standardised post-exercise meal [FastEx + NoMeal], (iii) fed exercise with a standardised post-exercise meal [FedEx + Meal], (iv) fed exercise without a standardised post-exercise meal [FedEx + NoMeal]. Studies must have measured ad libitum meal energy intake, within-lab energy intake, 24-h energy intake, energy expenditure, subjective hunger, acyl-ghrelin, peptide YY, and/or glucagon-like peptide 1.

Determinants of Peak Fat Oxidation Rates During Cycling in Healthy Men and Women.

This study explored lifestyle and biological determinants of peak fat oxidation (PFO) during cycle ergometry, using duplicate measures to account for day-to-day variation. Seventy-three healthy adults (age range: 19-63 years; peak oxygen consumption [V˙O2peak]: 42.4 [10.

Impact of pre-exercise feeding status on metabolic adaptations to endurance-type exercise training.

Nutrition and exercise metabolism are vibrant physiological fields, yet at times it feels as if greater progress could be made by better integrating these disciplines. Exercise is advocated for improving metabolic health, in part by increasing peripheral insulin sensitivity and glycaemic control. However, when a modest-to-high carbohydrate load is consumed before and/or during each exercise bout within a training programme, increases in oral glucose insulin sensitivity can be blunted in both men of a healthy weight and those with overweight/obesity.

The effects of glucose-fructose co-ingestion on repeated performance during a day of intensified rugby union training in professional academy players.

This study assessed the effects of glucose-fructose co-ingestion during recovery from high-intensity rugby training on subsequent performance. Nine professional, senior academy Rugby Union players performed two trials in a double-blind, randomized, crossover design. Identical rugby training sessions were separated by a 3-hour recovery period, during which participants ingested protein (0.

The day-to-day reliability of peak fat oxidation and FAT.

Purpose: Prior studies exploring the reliability of peak fat oxidation (PFO) and the intensity that elicits PFO (FAT) are often limited by small samples. This study characterised the reliability of PFO and FAT in a large cohort of healthy men and women.

Methods: Ninety-nine adults [49 women; age: 35 (11) years; [Formula: see text]Opeak: 42.

Physiological responses to maximal eating in men.

This study investigated metabolic, endocrine, appetite and mood responses to a maximal eating occasion in fourteen men (mean: age 28 (sd 5) years, body mass 77·2 (sd 6·6) kg and BMI 24·2 (sd 2·2) kg/m2) who completed two trials in a randomised crossover design. On each occasion, participants ate a homogenous mixed-macronutrient meal (pizza). On one occasion, they ate until 'comfortably full' (ad libitum) and on the other, until they 'could not eat another bite' (maximal).

Reliability of gastrointestinal barrier integrity and microbial translocation biomarkers at rest and following exertional heat stress.

Purpose: Exertional heat stress adversely distrupts (GI) barrier integrity and, through subsequent microbial translocation (MT), negativly impacts health. Despite widespread application, the temporal reliability of popular GI barrier integity and MT biomarkers is poorly characterised.

Method: Fourteen males completed two 80-min exertional heat stress tests (EHST) separated by 7-14 days.

Hydration status affects thirst and salt preference but not energy intake or postprandial ghrelin in healthy adults: A randomised crossover trial.

Background: Few studies have investigated the effect of hydration status on appetite for food in healthy adults. Prior work suggests hydration status does not alter appetite or energy intake, with mixed findings regarding appetite hormone secretion. However, an extensive investigation into both the psychological and physiological appetitive responses to hydration status has never been conducted.

Lipid Metabolism Links Nutrient-Exercise Timing to Insulin Sensitivity in Men Classified as Overweight or Obese.

Context: Pre-exercise nutrient availability alters acute metabolic responses to exercise, which could modulate training responsiveness.

Objective: To assess acute and chronic effects of exercise performed before versus after nutrient ingestion on whole-body and intramuscular lipid utilization and postprandial glucose metabolism.

Design: (1) Acute, randomized, crossover design (Acute Study); (2) 6-week, randomized, controlled design (Training Study).

Skipping Breakfast Before Exercise Creates a More Negative 24-hour Energy Balance: A Randomized Controlled Trial in Healthy Physically Active Young Men.

Background: At rest, omission of breakfast lowers daily energy intake, but also lowers energy expenditure, attenuating any effect on energy balance. The effect of breakfast omission on energy balance when exercise is prescribed is unclear.

Objectives: The aim of this study was to assess the effect on 24-h energy balance of omitting compared with consuming breakfast prior to exercise.

Effect of acute hypohydration on glycemic regulation in healthy adults: a randomized crossover trial.

The aim of this study was to investigate the acute effect of hydration status on glycemic regulation in healthy adults and explore underlying mechanisms. In this randomized crossover trial, 16 healthy adults (8 men, 8 women) underwent an oral glucose tolerance test (OGTT) when hypohydrated and rehydrated after 4 days of pretrial standardization. One day before OGTT, participants were dehydrated for 1 h in a heat tent with subsequent fluid restriction (HYPO) or replacement (RE).

Preexercise breakfast ingestion versus extended overnight fasting increases postprandial glucose flux after exercise in healthy men.

The aim of this study was to characterize postprandial glucose flux after exercise in the fed versus overnight fasted state and to investigate the potential underlying mechanisms. In a randomized order, twelve men underwent breakfast-rest [(BR) 3 h semirecumbent], breakfast-exercise [(BE) 2 h semirecumbent before 60 min of cycling (50% peak power output)], and overnight fasted exercise [(FE) as per BE omitting breakfast] trials. An oral glucose tolerance test (OGTT) was completed after exercise (after rest on BR).

Venous blood provides lower glucagon-like peptide-1 concentrations than arterialized blood in the postprandial but not the fasted state: Consequences of sampling methods.

New Findings: What is the central question of this study? Glucagon-like peptide-1 (GLP-1) is an important obesity/diabetes target, with effects dependent on circulating GLP-1 concentrations. Peripheral tissues extract GLP-1; therefore, sampling venous versus arterialized blood might provide different GLP-1 concentrations. This study examined whether arterialization alters GLP-1 concentrations during fasting and feeding.

Evaluation of a graded exercise test to determine peak fat oxidation in individuals with low cardiorespiratory fitness.

The maximal capacity to utilise fat (peak fat oxidation, PFO) may have implications for health and ultra-endurance performance and is commonly determined by incremental exercise tests employing 3-min stages. However, 3-min stages may be insufficient to attain steady-state gas kinetics, compromising test validity. We assessed whether 4-min stages produce steady-state gas exchange and reliable PFO estimates in adults with peak oxygen consumption < 40 mL·kg·min.

Prior exercise alters the difference between arterialised and venous glycaemia: implications for blood sampling procedures.

Oral glucose tolerance and insulin sensitivity are common measures, but are determined using various blood sampling methods, employed under many different experimental conditions. This study established whether measures of oral glucose tolerance and oral glucose-derived insulin sensitivity (insulin sensitivity indices; ISI) differ when calculated from venous v. arterialised blood.