Although the mechanisms underpinning short-term muscle disuse atrophy and associated insulin resistance remain to be elucidated, perturbed lipid metabolism might be involved. Our aim was to determine the impact of acipimox administration [i.e.
View Article and Find Full Text PDFThe mechanisms underpinning short-term muscle disuse atrophy remain to be elucidated, but perturbations in lipid metabolism may be involved. Specifically, positive muscle non-esterified fatty acid (NEFA) balance has been implicated in the development of disuse-induced insulin and anabolic resistance. Our aim was to determine the impact of acipimox administration (i.
View Article and Find Full Text PDFIncreasing skeletal muscle carnitine content can manipulate fuel metabolism and improve exercise performance. Intravenous insulin infusion during hypercarnitinemia increases plasma carnitine clearance and Na -dependent muscle carnitine accretion, likely via stimulating Na /K ATPase pump activity. We hypothesized that the ingestion of high-dose caffeine, also known to stimulate Na /K ATPase activity, would stimulate plasma carnitine clearance during hypercarnitinemia in humans.
View Article and Find Full Text PDFAnimal-derived dietary protein ingestion and physical activity stimulate myofibrillar protein synthesis rates in older adults. We determined whether a non-animal-derived diet can support daily myofibrillar protein synthesis rates to the same extent as an omnivorous diet. Nineteen healthy older adults (aged 66 (sem 1) years; BMI 24 (sem 1) kg/m2; twelve males, seven females) participated in a randomised, parallel-group, controlled trial during which they consumed a 3-d isoenergetic high-protein (1·8 g/kg body mass per d) diet, where the protein was provided from predominantly (71 %) animal (OMNI; n 9; six males, three females) or exclusively vegan (VEG; n 10; six males, four females; mycoprotein providing 57 % of daily protein intake) sources.
View Article and Find Full Text PDFContext: Anabolic resistance is mechanistically implicated in muscle disuse atrophy.
Objective: The objective of this study is to assess whether anabolic resistance is associated with reduced postprandial amino acid uptake or exacerbated by excess lipid availability.
Design, Setting, Participants, And Interventions: Twenty men underwent 7 days of forearm immobilization while consuming a eucaloric (CON; n = 11) or high-fat overfeeding (HFD; n = 9; 50% excess energy as fat) diet (parallel design) within our Nutritional Physiology Research Unit.
The world's population is expanding, leading to an increased global requirement for dietary protein to support health and adaptation in various populations. Though a strong evidence base supports the nutritional value of animal-derived dietary proteins, mounting challenges associated with sustainability of these proteins have led to calls for the investigation of alternative, non-animal-derived dietary protein sources. Mycoprotein is a sustainably produced, protein-rich, high-fiber, whole food source derived from the fermentation of fungus.
View Article and Find Full Text PDFContext: Physical inactivity and high-fat overfeeding have been shown to independently induce insulin resistance.
Objective: Establish the contribution of muscle disuse and lipid availability to the development of inactivity-induced insulin resistance.
Design, Setting, Participants, And Interventions: 20 healthy males underwent 7 days of forearm cast immobilization combined with a fully controlled eucaloric diet (n = 10, age 23 ± 2 yr, body mass index [BMI] 23.
The anabolic potential of a dietary protein is determined by its ability to elicit postprandial rises in circulating essential amino acids and insulin. Minimal data exist regarding the bioavailability and insulinotropic effects of non-animal-derived protein sources. Mycoprotein is a sustainable and rich source of non-animal-derived dietary protein.
View Article and Find Full Text PDFBackground: The protein leverage hypothesis requires specific evidence that protein intake is regulated more strongly than energy intake.
Objective: The objective was to determine ad libitum energy intake, body weight changes, appetite profile, and nitrogen balance in response to 3 diets with different protein-to-carbohydrate + fat ratios over 12 consecutive days, with beef as a source of protein.
Design: A 3-arm, 12-d randomized crossover study was performed in 30 men and 28 women [mean ± SD age: 33 ± 16 y; body mass index (in kg/m²): 24.