The Effects of Ketone Monoester Intake on Postprandial Myofibrillar Protein Synthesis Rates in Young Adults During Recovery Following an Acute Bout of Resistance Exercise
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 48
- 试验地点
- 1
- 主要终点
- Myofibrillar fractional synthesis rate
研究概览
简要总结
An acute bout of resistance exercise stimulates muscle protein synthesis (MPS) rates for up to 24-48 hours, supporting muscle growth and repair. To optimize the anabolic effects of resistance exercise, the provision of dietary amino acids (i.e., proteins) is essential. Dietary protein intake provides the body with necessary amounts of essential and non-essential amino acids, which represent the building blocks for muscle proteins, enhancing anabolic muscle growth. The ingestion of dietary protein, such as whey protein, is well established to stimulate an increase in the rate of protein synthesis in skeletal muscle following resistance exercise. Research has demonstrated a dose-dependent relationship between protein intake and MPS rate, with 25 grams being the optimal dose to maximally stimulate MPS rates in younger adults with excess protein oxidized as a fuel source.
Determining whether this maximally stimulated MPS response can be further heightened during post-exercise recovery using non-protein dietary factors is yet to be explored. Recently, it has been shown that novel orally ingested ketone body supplements can stimulate MPS rates in younger adults at rest.
Ketone bodies (β-OHB) are lipid- derived molecules normally produced under conditions of glucose deprivation (i.e., fasting/starvation, or a low carbohydrate 'ketogenic' diet). However, these orally ingested ketone supplements rapidly increase blood ketone levels without the need for dietary restriction6. In vitro research showed that the combination of leucine and ketone bodies stimulated a 2-fold increase in MPS, compared to the leucine group alone, indicating synergistic effects of protein and ketone bodies on MPS. However, the effect of ketone supplementation, with and without dietary protein co-ingestion, on MPS rate during post-exercise recovery is yet to be investigated. If ketone bodies can amplify the anabolic response to dietary protein, they may provide a novel approach to maximizing muscle adaptation during post-exercise recovery.
Therefore, the purpose of this study is to evaluate the effects of ketone monoester intake on postprandial muscle protein synthesis rates when consumed alone and when co-ingested with an optimal dose (25 g) of whey protein during recovery after resistance exercise compared to 1) an optimal dose of whey protein (25 g), and 2) a control flavored water. It is hypothesized that muscle protein synthesis rates will be stimulated following the ingestion of the ketone body beverage. Further, muscle protein synthesis rates will be further enhanced when the ketone-containing beverage and an optimal dose are taken together.
详细描述
A parallel group design will be used for this randomized double-blind, placebo-controlled study in healthy adults to investigate the effects of ketone monoester on myofibrillar protein synthesis rates during post-exercise recovery. There are 4 groups in this trial, including one ketone group (0.36g/kg body weight) (KET), one protein group (25 g whey protein) (PRO), a combination of ketone and protein (KET+PRO), and a placebo group (flavoured water) (CON). A total of 48 participants will be enrolled in this trial (n=12 per group).
The study will include a screening visit (visit 1), 10-repetition maximum (10-RM) testing (visit 2), where participants' 10-RM will be determined for the exercise protocol, and the experimental trial (visit 3).
During the experimental trials, participants will arrive to the laboratory in a fasted state, and a prime dose of the L-[ring-2H5]-phenylalanine will be administered followed by a continuous infusion at a rate 0.05 μmol/kg of body weight/min. Then, participants will perform a unilateral lower-body resistance exercise, consisting of 8 sets of 10 reps of unilateral leg extension at 90% of their 10-RM with 90 seconds rest in between sets. Following exercise, the nutritional treatment will be administered.
Arterialized blood will be collected at baseline and 13 postprandial timepoints across 9 hours for plasma amino acid, glucose, and insulin quantitation.
Additionally, changes in capillary blood β-HB concentration will be assessed throughout the trial by collecting capillary blood samples at baseline and 10 postprandial timepoints. Finally, muscle biopsy samples from both the exercised leg and the rested leg will be collected prior to beverage intake and at the 5-hour mark of the postprandial post-recovery period to assess myofibrillar protein synthesis rates.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Basic Science
- 盲法
- Triple (Participant, Investigator, Outcomes Assessor)
盲法说明
Participants, Investigators and Outcome Accessors will be blinded to the intervention and control drinks. The drinks will be flavor matched and provided in an opaque bottle. An individual not involved with the study data collection, analysis and interpretation will be designated as a study blinder and randomizer.
入排标准
- 年龄范围
- 18 Years 至 40 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Healthy adult female or male participants who are 18-40 years of age (inclusive) BMI >18.5 and <30.0 kg/m2
- •Moderately active (i.e., ≥ 1 session of lower-body weightlifting /week for the previous 2 months).
- •Has maintained stable use of medication and supplements (which are not limited by the
排除标准
- •), stable dietary and lifestyle habits, and stable body weight, for the last 3 months prior to screening and agree to maintain them throughout the study.
- •Be willing to entirely avoid alcohol consumption 48hr prior to the experimental test day.
- •Willing and able to agree to the requirements and restrictions of this study, be willing to give voluntary consent, be able to understand and read the questionnaires, and carry out all study-related procedures.
- •Exclusion Criteria:
- •Females who are lactating or pregnant
- •Females using third-generation oral contraceptives (including: Desogen®, Ortho-Cept, Ortho-Cyclen, Ortho Tri-Cyclen) as these are known to affect protein metabolism in females.
- •Individuals with metabolic disorders including: Type I or Type II diabetes
- •Individuals with a history of thrombosis / cardiovascular disease
- •Individuals who use of anticoagulants
- •Individuals with musculoskeletal / orthopedic disorders
- •Individuals with knee injuries (i.e., ACL injuries).
- •Individuals who have used tobacco products within the last 6 months
- •Individuals with a history of neuromuscular problems
- •Chronic usage of medications known to modulate skeletal muscle metabolism (i.e. corticosteroids, hormone replacement therapy (HRT), and over-the-counter supplements including creatine monohydrate) in the last 6 months.
- •Individuals with allergies to milk proteins (whey or casein).
- •Individuals with lactose intolerance
- •Individuals with Phenylketonuria (PKU)
- •Previous participation in amino acid tracer studies.
- •Adherence to a vegetarian or vegan diet
- •Current use of ketone supplements or adherence to a ketogenic diet
- •Individuals who train more than ≥ 5 sessions of lower-body weightlifting /week for the previous 4 months
结局指标
主要结局
Myofibrillar fractional synthesis rate
时间窗: 0 - 5 hours in the postprandial period.
Quantification of changes in basal myofibrillar fractional synthetic rate (%/hour) in the rested and exercised limbs.
次要结局
- Time-course data for plasma enrichments (in moles percent excess) of L-[ring-2H5]-phenylalanine(Baseline, 3 hours pre-prandial, and 5 hours into the postprandial period.)
- Incremental area under the curve for total amino acid concentration(3 hours pre-prandial to 5 hours postprandial)
- Time-course data for total amino acid concentration(Baseline, 3 hours pre-prandial, and 5 hours into the postprandial period.)
- Incremental area under the curve for essential amino acid concentration(3 hours pre-prandial to 5 hours postprandial)
- Time-course data for essential amino acid concentration(Baseline, 3 hours pre-prandial, and 5 hours into the postprandial period.)
- Incremental area under the curve for leucine concentration(3 hours pre-prandial to 5 hours postprandial)
- Time-course data for leucine concentration(Baseline, 3 hours pre-prandial, and 5 hours into the postprandial period.)
- Incremental area under the curve for glucose concentration(3 hours pre-prandial to 5 hours post-prandial)
- Time-course data for glucose concentration(Baseline, 3 hours pre-prandial, and 5 hours into the postprandial period.)
- Incremental area under the curve for insulin concentration(3 hours pre-prandial to 5 hours post-prandial)
- Time-course data for insulin concentration(Baseline, 3 hours pre-prandial, and 5 hours into the postprandial period.)
- Incremental area under the curve for β-HB concentrations(1 hour pre-prandial to 5 hours postprandial)
- Time-course data for β-HB concentrations(1 hour pre-prandial to 5 hours in the post-prandial period)
- Changes in the phosphorylation status of anabolic signaling molecules(0 and 5 hours of the postprandial period.)
研究者
Tyler Churchward-Venne
Associate Professor
McGill University