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Acute Ingestion of Ketone Monoesters and Precursors Do Not Enhance Endurance Exercise Performance: A Systematic Review and Meta-Analysis

Emma Brooks, Gilles Lamothe, Taniya S. Nagpal, Pascal Imbeault, Kristi Adamo, Jameel Kara, and Éric Doucet

) diet ( Cox & Clarke, 2014 ; Robinson & Williamson, 1980 ). Under all of these circumstances, KBs become a pertinent energy source while glucose is restricted or depleted. Ketosis, or hyperketonaemia, is defined as plasma ketone concentrations that exceed 0.2 mM, according to Robinson and Williamson

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Effects of Ketone Monoester and Bicarbonate Co-Ingestion on Cycling Performance in WorldTour Cyclists

Domingo Jesús Ramos-Campo, Francisco Javier López-Román, Silvia Pérez-Piñero, Raquel Ortolano, María Salud Abellán-Ruiz, Enrique Molina Pérez de los Cobos, Antonio Jesús Luque-Rubia, Dag Van Elslande, and Vicente Ávila-Gandía

and the heart, with greater contribution observed in exogenous ketosis ( Evans et al., 2017 ). Hyperketonemia is defined as a plasma ketone concentration above 0.5 mM ( Robinson & Williamson, 1980 ). β-Hydroxybutyrate (βHB) is the most common circulating ketone body, and exogenous ketones are often

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Acute Ketone Salts–Caffeine–Taurine–Leucine Supplementation but not Ketone Salts–Taurine–Leucine, Improves Endurance Cycling Performance

Manuel D. Quinones and Peter W.R. Lemon

endurance exercise performance because the resulting upregulated fat mobilization triggers a substantial increased accumulation of circulating ketone bodies. This is called nutritional ketosis ( Evans et al., 2017 ) and is characterized typically by a plasma ketone concentration of approximately 0.5–3.0 mM

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Fat-Free Mass Changes During Ketogenic Diets and the Potential Role of Resistance Training

Grant M. Tinsley and Darryn S. Willoughby

Low-carbohydrate and very-low-carbohydrate diets are often used as weight-loss strategies by exercising individuals and athletes. Very-low-carbohydrate diets can lead to a state of ketosis, in which the concentration of blood ketones (acetoacetate, 3-β-hydroxybutyrate, and acetone) increases as a result of increased fatty acid breakdown and activity of ketogenic enzymes. A potential concern of these ketogenic diets, as with other weight-loss diets, is the potential loss of fat-free mass (e.g., skeletal muscle). On examination of the literature, the majority of studies report decreases in fat-free mass in individuals following a ketogenic diet. However, some confounding factors exist, such as the use of aggressive weight-loss diets and potential concerns with fat-free mass measurement. A limited number of studies have examined combining resistance training with ketogenic diets, and further research is needed to determine whether resistance training can effectively slow or stop the loss of fat-free mass typically seen in individuals following a ketogenic diet. Mechanisms underlying the effects of a ketogenic diet on fat-free mass and the results of implementing exercise interventions in combination with this diet should also be examined.

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Metabolism and Whole-Body Fat Oxidation Following Postexercise Carbohydrate or Protein Intake

Ulrika Andersson-Hall, Stefan Pettersson, Fredrik Edin, Anders Pedersen, Daniel Malmodin, and Klavs Madsen

protein after the first session did not significantly affect this increase in fat oxidation, whereas maltodextrin intake somewhat attenuated the increase in fat oxidation during the second bout. Both PRO and CHO intake increased blood insulin levels and attenuated the postexercise ketosis seen after

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Ketone Monoester Ingestion Alters Metabolism and Simulated Rugby Performance in Professional Players

Oliver J. Peacock, Javier T. Gonzalez, Simon P. Roberts, Alan Smith, Scott Drawer, and Keith A. Stokes

and both made an estimated 16  kJ/kg body mass (BM) available for metabolism (total energy intake 1,528 ± 145 kJ). The ketone monoester was provided at a total dose of 590 mg/kg BM based on pilot data showing that this dosing level induces a sustained moderate ketosis (blood BHB of ∼2–3 mmol/L) that

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Acute Ketone Monoester Supplementation Impairs 20-min Time-Trial Performance in Trained Cyclists: A Randomized, Crossover Trial

Devin G. McCarthy, Jack Bone, Matthew Fong, Phillippe J.M. Pinckaers, William Bostad, Douglas L. Richards, Luc J.C. van Loon, and Martin J. Gibala

Nutritional ketosis induced through the ingestion of ketogenic supplements can alter physiological responses to exercise ( Evans et al., 2017 ). This practice has also been purported to enhance performance, at least under selected conditions, although the precise mechanistic basis is unclear

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Toward a Common Understanding of Diet–Exercise Strategies to Manipulate Fuel Availability for Training and Competition Preparation in Endurance Sport

Louise M. Burke, John A. Hawley, Asker Jeukendrup, James P. Morton, Trent Stellingwerff, and Ronald J. Maughan

CHO to avoid sustained ketosis. • Typical intake = 15–20% energy from CHO (<2.5 g −1 ·kg −1 ·day −1 ), 15–20% protein, 60–65% fat in combination with a moderate-endurance training volume (>5 hr/week). • Deprivation of CHO for muscle fuel needs while consuming high amounts of dietary fat causes

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Organization of Dietary Control for Nutrition-Training Intervention Involving Periodized Carbohydrate Availability and Ketogenic Low-Carbohydrate High-Fat Diet

Joanne G. Mirtschin, Sara F. Forbes, Louise E. Cato, Ida A. Heikura, Nicki Strobel, Rebecca Hall, and Louise M. Burke

moderate protein intake (<∼2 g/kg BM) to achieve chronic ketosis requires the elimination of many staple foods from the standard Western diet (e.g., most fruit, starchy vegetables and legumes, cereal products) and restrictions on the serving sizes of others. For example, there are portion limits on meats

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The Impact of a Short-Term Ketogenic Low-Carbohydrate High-Fat Diet on Biomarkers of Intestinal Epithelial Integrity and Gastrointestinal Symptoms

Alannah K.A. McKay, Alice M. Wallett, Andrew J. McKune, Julien D. Périard, Philo Saunders, Jamie Whitfield, Nicolin Tee, Ida A. Heikura, Megan L.R. Ross, Avish P. Sharma, Ricardo J.S. Costa, and Louise M. Burke

>0.5 mM on the morning of the Adaptation trial (range 0.6–2.6 mM) confirming ketosis ( Burke et al., 2021 ). Table 3 Physiological and Environmental Characteristics During the 25 km-Long Walk Protocol at Baseline and Adaptation in Athletes Adhering to the CON, LCHF, and LEA Dietary Intervention