Healthy
Conditions
Brief summary
Several previous studies observed a positive effect of beetroot supplementation on sports performance in athletes, mainly in endurance performance. However, less attention has been paid to its effects on short-duration performance, especially in youth athletes. Moreover, only a few previous investigations performed biochemical analyses, including pro-oxidant balance assessments. It is especially important because chronic nitrate intake might directly cause the production of reactive nitrogen species and reactive oxygen species in other subcellular compartments, leading to more oxidative stress. Additionally, no previous study verified the impact of beetroot intake on sleep.
Interventions
DIETARY_SUPPLEMENTBeetroot juice supplementation or placebo
Athletes received 7 days of beetroot juice supplementation with nitrate supplementation (2 × 70 mL of beetroot juice ∼12.9 mmol NO3-; Beet It, James White Drinks, Ipswich, UK) or placebo (2 × 70 mL of water with beetroot powder with negligible nitrate content).
Sponsors
University of Bergen
University School of Physical Education, Krakow, Poland
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
MALE
Age
14 Years to 23 Years
Healthy volunteers
Yes
Inclusion criteria
* male * good general health assessed by physician * highly trained * written consent to participate
Exclusion criteria
* medication or dietary supplements used within the previous month, which could potentially impact the study outcomes * history of sleep nor neurological disorders * chronic use (6 months) of any antibacterial mouthwash products.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Objective Sleep - Sleep efficiency | nights 1 - 7 during treatment | The percentage of total sleep time to lights off and leaving bed assessed by sleep radar |
| Performance test | 7 days after treatment | yo-yo intermittent recovery test level 1 |
| Changes in nitrates | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | Blood plasma will be obtained to measure nitrate concentration |
| Changes in nitrites | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | Blood plasma will be obtained to measure nitrite concentration |
| Changes in prooxidant status | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | Blood plasma will be obtained to measure total oxidative status |
| Changes in antioxidant status | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | Blood plasma will be obtained to measure total antioxidant capacity |
| Changes in oxidative stress index | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | The oxidative stress index will be calculated as the ratio of plasma prooxidant to antioxidant status |
| Changes in nitrooxidative stress markers | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | Blood plasma will be obtained to measure 3-nitrotyrosine concentration |
| Changes in protein oxidation | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | Blood plasma will be obtained to measure advanced protein oxidation products concentration |
| Changes in nucleic acid oxidation | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | Blood plasma will be obtained to measure ox-8-hydroxy-2'-deoxyguanosine (8-OHdG) concentration |
| Changes in lipids oxidation | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | Blood plasma will be obtained to measure thiobarbituric acid reactive substances concentration |
| Changes in exercise-induced metabolic acidosis | 1) Before the performance test 2) 3 minutes after the performance test 3) 10 minutes after the performance test 4) 20 minutes after the performance test | Arterialized blood will be obtained to measure lactate concentration |
| Objective Sleep - Time in bed | nights 1 - 7 during treatment | Total time spent in bed during the night assessed by sleep radar |
| Objective Sleep - Sleep-onset latency | nights 1 - 7 during treatment | The time it takes from when the athlete intends to go to sleep and actually starts to sleep assessed by sleep radar |
| Objective Sleep - Total sleep time | nights 1 - 7 during treatment | Total sleep time obtained from sleep onset to time at wake-up assessed by sleep radar |
| Objective Sleep - Light sleep | nights 1 - 7 during treatment | Total amount of time in light sleep assessed by sleep radar |
| Objective Sleep - Deep sleep | nights 1 - 7 during treatment | Total amount of time in deep sleep assessed by sleep radar |
| Objective Sleep - REM sleep | nights 1 - 7 during treatment | Total amount of time in REM sleep assessed by sleep radar |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Ball speed velocity | 7 days after treatment | — |
| Sprint test (0-20m) | 7 days after treatment | — |
| Agility T-test | 7 days after treatment | — |
| Maximal isometric handgrip strength | 7 days after treatment | — |
| Flanker task | 7 days after treatment | — |
| Changes in muscle damage markers | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | Blood serum will be obtained to measure myoglobin concentration |
| Changes in muscle enzymes activity | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | Blood serum will be obtained to measure creatine kinase activity |
| Changes in inflammation markers | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | Blood serum will be obtained to measure C-reactive protein concentration |
| Changes in blood count | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | Whole blood will be obtained to measure leukocyte count |
| Changes in anabolic hormones | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | Blood serum will be obtained to measure testosterone concentration |
| Changes in catabolic hormones | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | Blood serum will be obtained to measure cortisol concentration |
| Changes in kidney function markers | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | Blood serum will be obtained to measure creatinine concentration |
| Changes in the purine metabolism marker | 1) baseline - 2) 7th day of treatment - before the supplementation, 3) 7th day of treatment - before the performance test, 4) 7th day of treatment - immediately after the performance test | Blood serum will be obtained to measure uric acid concentration |
| Changes in hemoglobin concentration | 1) Before the performance test 2) 3 minutes after the performance test 3) 10 minutes after the performance test 4) 20 minutes after the performance test | Arterialized blood will be obtained to measure hemoglobin concentration |
| Changes in hematocrit | 1) Before the performance test 2) 3 minutes after the performance test 3) 10 minutes after the performance test 4) 20 minutes after the performance test | Arterialized blood will be obtained to measure hematocrit |
| Changes in plasma volume | 1) Before the performance test 2) 3 minutes after the performance test 3) 10 minutes after the performance test 4) 20 minutes after the performance test | The change in plasma volume will be calculated using the hemoglobin and hematocrit results |
| Countermovement jump height | 7 days after treatment | — |
Countries
Poland
Outcome results
None listed