Time-trial Performance, Submaximal Exercise Performance, Nitrite, Nitrate
Conditions
Keywords
Nitrate, Performance, Sports
Brief summary
The main aim of the current study will be to find the optimal duration of supplementation to enhance sports performance.
Detailed description
Oral ingestion of nitrate (NO3-) in the form of both nitrate salts and beetroot juice has been shown to significantly lower blood pressure at rest and to also lower pulmonary oxygen uptake during exercise, in addition to improving exercise performance during cycle time trial. However, there has been no consensus on the optimal supplementation protocols, in terms of duration of supplementation to see these metabolic effects. Furthermore, a positive exercise performance effect of nitrate ingestion has primarily been observed in recreational athletes. The potentially ergogenic effects of nitrate in well-trained or elite athletes therefore remain to be fully established. Based on the gaps in current literature, our main goal will be to gain further insight into different aspects of nitrate supplementation to enhance (elite) sports performance. This will be investigated in this study by assessing the effect of an acute vs. chronic supplementation period of sodium nitrate (NaNO3-) on exercise performance.
Interventions
DIETARY_SUPPLEMENTSodium Nitrate
DIETARY_SUPPLEMENTSodium Chloride
Sponsors
Maastricht University Medical Center
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
MALE
Age
18 Years to 35 Years
Healthy volunteers
Yes
Inclusion criteria
* 18.5 \< BMI \< 25 kg/m2 * Endurance trained cyclists/triathletes (with at least 1 year of competitive cycling experience) * VO2max ≥ 55 mL/kg/min
Exclusion criteria
* Use of medication * Injury prohibiting them from performing the exercise protocol effectively * Smoking * Currently supplementing diet with nitrate * Lactose intolerance
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Time-trial exercise performance | Time trial starts 4 hours after ingestion and ends on average after 15 minutes of cycling (depending on subject's cycling speed) | The primary outcome measure will be the time to complete the time-trial following dietary nitrate or placebo ingestion |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Resting blood pressure | 30 min pre-ingestion until 2.5 hours post-ingestion | Resting blood pressure measures following ingestion of dietary nitrate |
| Plasma nitrate and nitrite levels | 30 min pre-ingestion until 30 min post-time-trial testing | Plasma nitrate and nitrite levels following ingestion of dietary nitrate |
| Submaximal exercise performance | starting from 3 hours post-ingestion on testing days until completion of the submaximal exercise | Oxygen consumption CO2 production and heart rate during submaximal exercise |
| Time-trial exercise performance; power output and heart rate | starting from 4 hours post-ingestion on testing days until completion of the time-trial | Power output and heart rate during the time-trial exercise |
Other
| Measure | Time frame | Description |
|---|---|---|
| Baseline characteristics and fitness level assessment | 3 hours during visit 1 (Screening) | Resting blood pressure, height, body weight, age, BMI, measures of GI tolerance, VO2 max, Wmax, rate of perceived exertion |
Countries
Netherlands
Outcome results
None listed