Search clinical trials by condition, location and status
The purpose of the study is to quantify and compare the serum nutrient and hormonal profile, and muscle protein synthesis rates, in response to consuming isonitrogenous amounts of a traditional East African meal, mung bean stew with a traditional African corn bread made from two different kinds of maize (whole corn flour or refined). Specific aim 1: Describe the post-prandial nutrient and hormonal profile in serum in the 3 hours following consumption of a portion of mung bean stew with traditional African corn bread made with either whole grain maize flour or refined maize flour. Specific aim 2: Compare the ability a portion of mung bean stew and traditional African corn bread made with either whole grain maize flour or refined maize flour to activate mTORC1-specific and whole muscle protein synthesis in an in vitro model of muscle.
The study aims to evaluate if there is a difference between eating conventionally raised or organic chicken. The investigators will measure and compare the nutrient and hormone levels in the participant's blood and the muscle protein synthesis rate (the rate at which your body builds muscle) after eating chicken from different farming practices. This will help the investigators to understand if these farming practices impact muscle protein synthesis and overall health. Specific aim 1: Describe the post-prandial nutrient and hormonal profile in serum in the 3 hours following consumption of 100 grams (\~32g of protein) of boneless-skinless conventional vs. regenerative chicken breast meat. Specific aim 2: Compare the ability of boneless-skinless chicken breasts grown with these two farming practices to activate mTORC1-specific and whole muscle protein synthesis in an in vitro model of muscle.
Bariatric surgery is an effective treatment for severe obesity but results in loss of muscle mass. The investigators will test the hypothesis that consumption of an Essential Amino Acid-based nutritional formulation will maintain muscle mass while stimulating fat loss after bariatric surgery.
Traditionally, when performing resistance exercise, repetitions are performed in a continuous manner resulting in a decrease in velocity, and thus power output. "Cluster" set is an alternative to counter the reduction in velocity and power output. Cluster sets incorporate a brief rest (15-30 seconds) between individual repetitions (inter-repetition rest) or group of repetitions (intra-set rest) within a set of resistive exercise. In contrast to traditional set configurations, which result in an almost linear decrease in force, velocity, and power -cluster sets maintain and/or attenuate the loss in power, primarily due to higher velocities. The purpose of this research is to compare the muscle protein synthesis response to acute bouts of cluster and traditional set configurations. Investigators will assess muscle protein synthesis rates before and after acute resistance exercise in 14 resistance-trained males and females (Age: 20-35; back squat 1.5 x body weight; 3 years of resistance training experience). The volunteers are required to be removed (at least six weeks) from all ergogenic levels of nutritional supplements that have previously been shown to affect protein synthesis. Blood and muscle biopsies will be collected as a part of testing. Further, subjects will be required to perform moderate-to-high intensity resistance exercise.
In a crossover design 10 young healthy adults (20-35 y) will receive stable isotope tracer infusions and perform a single bout of resistance exercise. Immediately after exercise participants will ingest either 3.5 oz of Salmon fillet or its constituent macronutrients as isolated amino acids and fat. Repeated blood and breath samples as well as muscle biopsies will be collected to determine whole body amino acid kinetics, muscle amino acid transporters, anabolic signalling and myofibrillar protein synthesis rates during the trials
The most severe form of chronic renal failure is end-stage-renal-disease with maintenance hemodialysis (MHD) as the most common treatment strategy. MHD patients experience a number of metabolic and phenotypic derangements including skeletal muscle wasting. Previously, it has been demonstrated that dialysis treatment leads to increased rates of forearm phenylalanine uptake (proxy for 'muscle' protein synthesis) with an even greater rates of phenylalanine release (proxy for 'muscle' protein breakdown). Hence, the dialysis procedure itself is catabolic and induces a catabolic carryover for several hours after dialysis. This suggests prolonged post-dialysis disturbances in whole body- and skeletal muscle protein metabolism in MHD patients. Moreover, dialysis treatment in itself results in \~20 % losses of circulating amino acids in the dialysate. Collectively, this creates the need for replacement of amino acids by protein supplementation during and/or after dialysis. The ingestion of protein-dense meals in between dialysis treatments likely represents an important dietary strategy to counterbalance dialysis-induced catabolism and to achieve the current recommended protein intakes (set at 1.2 g/kg bodyweight/d) to limit muscle protein loss in MHD patients. However, the effectiveness of protein-rich meal ingestion to augment postprandial whole body and muscle protein metabolic responses in MHD patients outside of the dialysis period remain largely undefined. The purpose of this study is to compare basal and postprandial whole body leucine body kinetics, muscle anabolic sensing mechanisms, markers of muscle proteolysis, and myofibillar protein synthesis rates to mixed meal ingestion on a non-dialysis day in eight MHD patients, between 20-80 and to compare these outcomes to age- and BMI-matched controls. The investigators will use specifically produced intrinsically L-\[5,5,5-2H3\]leucine labeled eggs combined with primed constant amino acid tracer infusion methods and concomitant blood and muscle direct sampling to make direct assessments of in vivo protein digestion and absorption kinetics and subsequent postprandial muscle protein synthetic responses in MHD patents and controls. On the test day, subjects will remain sedentary for the determination of muscle protein synthesis in both the fasted state and after consumption of the meal.
Obesity has numerous comorbidities that are associated with exceedingly high healthcare costs. In addition to well- characterized impairments in lipid and glucose metabolism, obesity is associated with altered protein metabolism. We have recently observed that obese individuals are essentially nonresponsive to protein ingestion with respect to myofibrillar protein synthesis. This suggests that skeletal muscle remodeling in obese individuals is impaired possibly contributing to a poor metabolic quality of muscle. Resistance exercise is known to strongly augment muscle protein synthesis in response to protein ingestion. The purpose of this research is to determine the muscle protein synthetic response during post-exercise recovery in obese individuals. Using stable isotope methodology, we will determine the postprandial muscle protein synthetic response in 14 male and female obese adults (Age: 20-45, BMI: 30-39.9 kg/m2) immediately after an acute bout of resistance exercise. Participants will be sedentary (\< 60 min exercise/ week) and weight stable for a minimum of 6 months. During the testing blood and muscle samples will be collected. In addition participants will be asked to perform moderate intensity resistance exercise. Completion of the proposed research will identify the role of resistance exercise in the maintenance of skeletal muscle tissue after the consumption of a protein-dense meal in obese people.
Muscle protein synthesis can be stimulated by ingestion of protein sources, such as whey, casein or soy. Protein supplementation can be useful to restore protein turnover after exercise but also to preserve skeletal muscle mass and function in aging adults. Ingestion of large doses of essential amino acids (EAA) or certain protein supplements may be an effective strategy to induce muscle protein synthesis. However, in many cases, it may not be practical or feasible to consume a large volume of amino acids or protein required for an effective response by muscle. Several evidences show how reduced strength and muscle mass, even in early life, are predictors of early mortality which explicit the importance of developing more effective methods to improve muscle quality. Therefore, identifying the better sources of protein that have higher anabolic potency is of high significance. The goal of this study is to determine the anabolic potency and efficacy of a new and novel Whey Protein Hydrolysate mixture (WPH) on skeletal muscle protein synthesis in healthy young subjects (age 20-35 yr). Previous studies on rats indicate WPH induces significant increases in muscle protein synthesis compared with carbohydrates or whey-amino acid mixture. WPH contains mostly peptides, which have physiological effects and could be absorbed more rapidly. Preliminary data from preclinical study has also demonstrated that WPH can stimulate muscle protein synthesis at lower doses compared with intact whey proteins. Thus, WPH could be absorbed more rapidly and may maximally stimulate muscle protein synthesis. Although there is substantial data on the individual effects of BCCA and intact protein such as whey, there have been no clinical investigations that have explored the efficacy of WPH for stimulating muscle protein synthesis in humans. Therefore, the investigators propose that WPH will increase muscle protein synthesis. They will compare the response of WHP to the response of WHEY when equal protein is provided in both treatments. 10 healthy subjects will be recruited and will receive both WPH and WHEY supplementation in a single blind crossover design. Muscle protein synthesis will be measured on both occasions. This acute study will allow to determine whether low dose WPH supplementation will be an effective nutritional treatment to stimulate muscle protein synthesis in young adults.
In crossover trials, ten (N=10) young men (18-35 y) will receive stable isotope tracer infusions and perform a single bout of resistance exercise. Immediately after resistance exercise, participants will ingest stable isotope labeled whole eggs (18 g protein, 17 g fat) or egg whites (18 g protein, 0 g fat) cooked in scrambled form. Repeated blood and muscle biopsies will be collected to determine whole body amino acid kinetics, muscle amino acid transporters, anabolic signaling and myofibrillar protein synthesis rates during the trials.
During aging there is a tendency for muscle protein synthesis (growth) to become less efficient and the resulting consequence leads to reduced muscle mass (sarcopenia) which can affect strength and mobility. Protein consumption may be one opportunity to alleviate this problem especially when consumed in appropriate amounts following resistance training. This study is designed to determine if a soy dairy protein blend, shown to be effective in younger adults, will produce beneficial muscle protein synthesis in older healthy adults following resistance exercise.