Adaptation Reaction, Inflammation, Oxidative Stress
Conditions
Keywords
altitude training, antioxidants, oxidative stress, elite athletes, inflammation, diet
Brief summary
Athletes, especially in endurance sports, are at increased risk of oxidative stress and inflammation-related diseases and injuries. The production of reactive oxygen and nitrogen species (RONS) and inflammatory markers increase during exercise and especially during altitude training. Antioxidant supplementation is commonly used among athletes in the belief that it prevents oxidative stress and oxidative damage. A transient increase of RONS is however necessary to activate signaling cascades initiating training adaptation. Antioxidant supplementation has been shown to inhibit the exercise effects in several independent studies, possibly by interfering/reducing the signal cascades initiated by RONS. However, it is unknown whether a high intake of antioxidant rich foods can affect the amount of RONS, inflammation markers and/or training adaptation. The investigators want to examine whether an increased intake of natural antioxidants in the form of antioxidant-rich foods fruits, vegetables and berries, in line with the official Norwegian dietary advice can affect antioxidant status, immune function and training adaptation associated with altitude training in Norwegian elite athletes.
Interventions
OTHERAntioxidant-rich snacks
Bama Smoothies (Bama, Oslo, Norway), Freia Premium Dark Chocolate (Freia, Oslo, Norway), Walnuts (Eldorado, Norway), Dried fruits and berries (Cranberries, Gojiberries, apricots)(Bama, Oslo, Norway and Rema 1000, Norway)
OTHERControl snacks
Milkshake (Tine, Oslo, Norway), YT restitusjonsdrikk (Tine, Oslo, Norway), Bixit (Sætre, Oslo, Norway), Ritz (Mondelez, Oslo, Norway), White chololate (Freia, Oslo, Norway)
Sponsors
Norwegian School of Sport Sciences
Norwegian Olympic Federation, Oslo, Norway
University of Oslo
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
16 Years to 42 Years
Healthy volunteers
No
Inclusion criteria
* National team athletes, summer endurance sports
Exclusion criteria
* Allergies in conflict with the intervention foods * Use of medication that could affect training and performance * Injuries that could affect training and performance
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Percent change in performance (sport specific tests will be aggregated to one outcome by the use of percent change) | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | Cycling: 10 000 m on a bike roller; Rowing: 2000 meter on Concept2-apparatus; Paddling: 1000 meter Concept2-apparatus; Swimming: 200 meter |
| Training adaptation | Measured one week before, and one week after the moderate altitude training camp | change in Vo2-max |
| Training adaptation for swimmers | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | For swimming only: 100 meter max speed |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Bone mineral density | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | measured by DXA (iDXA; GE Healthcare) |
| change in fat mass | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | measured by DXA (iDXA; GE Healthcare) |
| change in body composition | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | measured by DXA (iDXA; GE Healthcare) |
| change in body weight | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | measured by standardized scale |
| Dietary intake (change in food and nutrient intake) | Measured one and three week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | measured by repeated 24 hour recalls |
| Change in antioxidant status | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | e.g. FRAP, ORAC, dROM, isoprostanes measured by HPLC |
| biomarkers of antioxidant-rich foods | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | e.g. carotenoids, flavonoids measured by HPLC |
| Change in whole blood gene expression | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | Fasting blood samples (PAX-tubes) and samples taken after physical stress test (PAX-tubes). RNA will be isolated and gene expression measured |
| Total training load | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | Training diary |
| Change hormones | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | — |
| Change in micronutrients | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | e.g. iron status |
| change in blood volume | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | CO-rebreathing-method |
| change in plasma volume | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | CO-rebreathing-method |
| Change in lactate | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | — |
| change response to stress test | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | — |
| Change in hemoglobin | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | CO-rebreathing-method |
| Change in blood lipids | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | — |
| Change in biomarkers of inflammation | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | change in cytokine profile e.g. IL-6 ,TNF, CRP measured by multiplex technology |
| change in lean body mass | Measured one week before, during (in week 1 and 3 of the camp) and one week after the moderate altitude training camp | measured by DXA (iDXA; GE Healthcare) |
Countries
Norway
Outcome results
None listed