The Impact of Protein Intake on Protein Metabolism During Intensified Training
Study Details
Study Description
Brief Summary
Protein requirements in individuals who participate in endurance-based exercise training have been suggested to be greater than the current recommended dietary allowance (RDA).
Our recent study using the minimally invasive indicator amino acid oxidation (IAAO) technique have suggested that protein requirements in young men are at least 30% higher than the recommended protein intake.
The present study will investigate the impact of protein sufficiency on protein metabolism and performance during intensified training periods as a means to further our understanding of the nutritional requirements for the endurance athlete.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: Normal protein intake participants will receive the controlled-diet containing 0.8 g protein /kg/day and the test drink containing 0.14 g protein/kg/d. |
Dietary Supplement: Normal
test drink which contains low amount of amino acids (0.14 g/kg/day)
Other: Controlled-diet
the diet containing 0.8 g protein /kg/day
|
| Experimental: Moderate protein intake participants will receive the controlled-diet containing 1.20 g protein /kg/day and the test drink containing 0.40 g protein/kg/d. |
Dietary Supplement: Moderate
test drink which contains moderate amount of amino acids (0.40 g/kg/day)
Other: Controlled-diet
the diet containing 0.8 g protein /kg/day
|
| Experimental: High protein intake participants will receive the controlled-diet containing 1.83 g protein /kg/day and the test drink containing 1.03 g protein/kg/d. |
Dietary Supplement: High
test drink which contains high amount of amino acids (1.03 g/kg/day)
Other: Controlled-diet
the diet containing 0.8 g protein /kg/day
|
Outcome Measures
Primary Outcome Measures
- Change in 24h whole body protein balance [Difference between day 1 and day 4 whole body protein balance]
Protein balance (mg/kg/d; protein synthesis - protein breakdown) will be measured using [15N]Glycine method on day 1 and day 4 to determine the change over the intensified training period to compare between protein levels
Secondary Outcome Measures
- Change from baseline physical performance (5 km time trial) 5days after the beginning of training [5days after the beginning of training]
Before and after 4 days of intensified training period, Duration (seconds) for completing 5-km running on treadmill will be measured.
- change from baseline Physical performance (muscle strength) 5days after the beginning of training [5days after the beginning of training]
Maximal strength will be assessed by a maximal isometric voluntary contraction (MVC), which will be tested for the knee-extensors using a custom-made knee-extension apparatus after 4 days intensified training.
- change from baseline Physical Performance (muscle power) 5days after the beginning of training [5days after the beginning of training]
Peak lower body power will be measured by force platform after 4days-intensified training.
Other Outcome Measures
- Creatine Phosphate Kinase activity on day 5 [5days after the beginning of training]
Muscle damage markers (blood Creatine Phosphate Kinase activity, IU/L) will be compared between the experimental arms 5days after the beginning of training
- Myoglobin concentration on day 5 [5days after the beginning of training]
Muscle damage markers (blood Mb Concentration, mg/mL) will be compared between the experimental arms 5days after the beginning of training
- IL-6 concentration on day 5 [5days after the beginning of training]
inflammatory markers (IL-6 concentration, pg/ml) will be compared between the experimental arms 5days after the beginning of training
- CRP concentration on day 5 [5days after the beginning of training]
inflammatory markers (CRP concentration, mg/L) will be compared between the experimental arms 5days after the beginning of training
- amino acid concentration on day 5 [5days after the beginning of training]
amino acid concentration (mmol/mL) will be compared between the experimental arms 5days after the beginning of training
Eligibility Criteria
Criteria
Inclusion Criteria:
-
Healthy, male, endurance-trained participants who have run regularly more than 45 km or 4.5 hours/week
-
Participants who are categorized at least "very good" based on a study by Shvartz & Reibold [40], in which peak rate of oxygen consumption(VO2 Peak) is used as an index. (i.e. the participants whose VO2peak is ≥57 ml/kg/min (18-24 y), ≥54 ml/kg/min (25-29 y), ≥52 ml/kg/min (30-34 y), ≥49 ml/kg/min (35-39 y), ≥47 ml/kg/min (40-44 y), ≥44 ml/kg/min (45-50 y) according to his age,
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Participants who can cover 10 km in less than 60 min after the VO2peak test and 5 km Time trial on session 2.
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Participants will be 18-50 years old.
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Participants are willing to abide by the compliance rules of this study
Exclusion Criteria:
-
Inability to meet health and physical activity guidelines according to the The Physical Activity Readiness Questionnaire for everyone.
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Female
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Inability to adhere to any of the compliance rules judged by principal investigator or medical doctor
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Regular tobacco use
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Illicit drug use (e.g. growth hormone, testosterone, etc.)
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Goldring Centre For High Performance Sport | Toronto | Ontario | Canada | M5S 2C9 |
Sponsors and Collaborators
- University of Toronto
- Ajinomoto Co., Inc.
Investigators
- Principal Investigator: Daniel Moore, Ph.D., Faculty of Kinesiology and Physical Education, University of Toronto
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- PFE