ALTAX: Effect of an Antioxidant-rich Diet During Moderate Altitude Training

Sponsor

University of Oslo (Other)

Overall Status

Completed

CT.gov ID

NCT03088891

Collaborator

Norwegian School of Sport Sciences (Other), Norwegian Olympic Federation, Oslo, Norway (Other)

Enrollment

Locations

Arms

Duration (Months)

17.5

Patients Per Site

17.2

Patients Per Site Per Month

Study Details

Study Description

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.

Condition or Disease	Intervention/Treatment	Phase
Oxidative Stress Adaptation Reaction Inflammation	Other: Antioxidant-rich snacks Other: Control snacks	N/A

Study Design

Study Type:

Interventional

Actual Enrollment :

35 participants

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Masking:

Triple (Participant, Investigator, Outcomes Assessor)

Primary Purpose:

Basic Science

Official Title:

The Effect of an Increased Intake of Antioxidant-rich Foods on Training Adaptation, Redox-balance and Inflammation Among Elite Athletes During a Moderate Altitude Training Camp

Study Start Date :

Oct 1, 2015

Actual Primary Completion Date :

Nov 1, 2015

Actual Study Completion Date :

Nov 1, 2015

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Antioxidant-rich snacks The participants received antioxidant-rich snacks every day during 21 days of moderate altitude training (2300 meters above sea level). The snack included fruits and vegetable smoothies, dark chocolate, walnuts, dried fruits and berries.	Other: Antioxidant-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)
Placebo Comparator: Control snacks The participants received antioxidant-depleted snacks every day during 21 days of moderate altitude training (2300 meters above sea level). The snack included milkshake, and other milk-based drinks, biscuits (both sweet and salty), white chocolate.	Other: Control snacks Milkshake (Tine, Oslo, Norway), YT restitusjonsdrikk (Tine, Oslo, Norway), Bixit (Sætre, Oslo, Norway), Ritz (Mondelez, Oslo, Norway), White chololate (Freia, Oslo, Norway)

Arm

Intervention/Treatment

Experimental: Antioxidant-rich snacks

The participants received antioxidant-rich snacks every day during 21 days of moderate altitude training (2300 meters above sea level). The snack included fruits and vegetable smoothies, dark chocolate, walnuts, dried fruits and berries.

Other: Antioxidant-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)

Placebo Comparator: Control snacks

The participants received antioxidant-depleted snacks every day during 21 days of moderate altitude training (2300 meters above sea level). The snack included milkshake, and other milk-based drinks, biscuits (both sweet and salty), white chocolate.

Other: Control snacks

Milkshake (Tine, Oslo, Norway), YT restitusjonsdrikk (Tine, Oslo, Norway), Bixit (Sætre, Oslo, Norway), Ritz (Mondelez, Oslo, Norway), White chololate (Freia, Oslo, Norway)

Outcome Measures

Primary Outcome Measures

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 Outcome Measures

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)
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
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 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 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 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]
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