Exercise Training
Conditions
Brief summary
Study will investigate the impact of training volume on protein metabolism to estimate the impact on daily protein requirements of endurance athletes.
Interventions
OTHEREndurance exercise
On the trial day before commencing the indicator amino acid oxidation metabolic trial, participants will either rest, perform a 10km run on a treadmill, or perform a 20km run on a treadmill.
Sponsors
University of Toronto
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
MALE
Age
18 Years to 40 Years
Healthy volunteers
Yes
Inclusion criteria
Healthy, male, endurance-trained participants who regularly run more than 40 km/week or perform endurance exercise for more than 4.5 hours/week * Participants who have a self-reported 5-km run time of ≤23 min * Participants who are categorized as at least very good based on a study by Shvartz & Reibold (Aviat Space Environ Med. 1990 Jan;61(1):3-11), in which VO2peak 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) * Ability to complete the 16-km familiarization run on Session 2 * Aged 18-40 years old
Exclusion criteria
* \- Inability to meet health and physical activity guidelines according to the PAR-Q+. * Female: hormonal fluctuations associated with the menstrual cycle have been reported to alter protein metabolism during exercise and may influence specific amino acid requirements at rest; as such, the present study will test the effect of endurance exercise on protein requirements in males only to ensure a stable hormonal environment and to increase the homogeneity of the physiological response. (NOTE: we plan to test females in a future trial based off of the results obtained herein) * Inability to adhere to any of the protocol guidelines (i.e. alcohol, caffeine consumption) * Regular tobacco use * Illicit drug use (e.g. growth hormone, testosterone, etc.)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Phenylalanine excretion | 8 hours | Excretion of 13CO2 in the breath will be used to estimate the impact of exercise on daily protein requirements. This outcome will include the enrichment of 13CO2 in exhaled breath after the ingestion of \[13C\]phenylalanine tracer and the production of CO2 determined by indirect calorimetry at rest or after exercise. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Phenylalanine flux | 8 hours | The enrichment of \[13C\]phenylalanine in the urine will be used to estimate the flux of phenylalanine in the body at rest or after exercise. |
| Phenylalanine oxidation | 8 hours | The oxidation of \[13C\]phenylalanine will be determined by correcting phenylalanine excretion by phenylalanine flux. |
Countries
Canada
Outcome results
None listed