Effects of Isotonic Beetroot Supplementation on Sprint Interval Exercise Performance

NCT06349018 | Completed

• 1 other identifier: IRB-2023-972
• Study Type: interventional
• Target: 24
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to examine the effects of dietary nitrate supplementation via beetroot juice on sprint interval cycling exercise performance. Twenty-four participants (male or female) will undertake a randomized, crossover trial where they consume either (i) an isotonic beetroot juice drink containing nitrate (12.9 mmol) for 5 days or (ii) an isotonic sports drink (no nitrate) for 5 days. On Day 5 of each trial, participants will come to the laboratory and 2 hours after consuming their allocated drink will complete a 6 bouts of sprint interval exercise. Power output during cycling will be measured as the primary outcome measure. Salivary and plasma measures of nitrate and nitrite will be taken over the course of the morning on Day 5. After a 5-day washout period participants will crossover and begin their second trial.

Conditions

Exercise Performance

Outcome Measures

Primary Outcomes (1)

• Power output during maximal sprint cycling

  Peak and mean power output

  2 hours after drink ingestion

Secondary Outcomes (5)

• Salivary nitrate

  Pre-drink, 2 hours post-drink and immediately post-exercise (2.5 hours post-drink)

• Plasma nitrate and nitrite

  Pre-drink and 2 hours post-drink

• Muscle oxygenation

  During exercise (2-2.5 hours post drink)

• Sensory evaluation (Acceptance and Preference Test Evaluation by Meilgaard et al 2007)

  Immediately post-drink (1 minute post-drink)

• Stroop test

  Immediately pre- (2 hours post-drink) and immediately post-exercise (2.5 hours post drink)

Study Arms (2)

High nitrate

EXPERIMENTAL

High nitrate isotonic drink

Other: Dietary Supplement: High nitrate isotonic drink

No nitrate

ACTIVE COMPARATOR

No nitrate isotonic drink

Other: Dietary Supplement: No nitrate isotonic drink

Interventions

Dietary Supplement: High nitrate isotonic drink OTHER

High nitrate (12.9 mmol) drink with carbohydrate and minerals

High nitrate

Dietary Supplement: No nitrate isotonic drink OTHER

Carbohydrate and mineral isotonic drink

No nitrate

Eligibility Criteria

• Age: 21 Years - 40 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Age: 21 - 40 years
• Healthy and injury-free (e.g., no cardiovascular disease, diabetes mellitus, orthopaedic impairment that interferes with moderate-to-vigorous exercise)
• Blood pressure \< 130/90 mmHg
• Be physically active: Engaging in a minimum of 150 minutes of moderate-intensity exercise or 75 minutes of vigorous-intensity physical activity each week.
• Recreational cyclist (Minimum 1 hour cycling per week).
• Body mass index: 18.5-25 kg/m2
• Non-smoker
• Asian

You may not qualify if:

• Any allergies to beetroot or isotonic drink.
• Asthma
• Any diagnosed form of cardiometabolic disease (heart disease, stroke, peripheral vascular disease, diabetes, metabolic syndrome, high blood pressure).
• Any symptoms contraindicating exercise testing (e.g. chest pains).
• Any balance or dizziness problems.
• Any chronic medical conditions (whether medicated or not).
• Any bone joint problems.
• Any Physician diagnosed contraindications to exercise.
• Any other health problems that may be a cause for concern or contraindication to exercise.
• Any recent Covid vaccination (within last 2 weeks).

Sponsors & Collaborators

• Nanyang Technological University: lead

Study Sites (1)

Human Bioenergetics Laboratory, National Institute of Education, Nanyang Technological University

Singapore, 637616, Singapore

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Masking Details: Both isotonic drinks (high nitrate or no nitrate) are deidentified and labelled (coded) by a third party not involved with the research. Randomization and allocation are completed by a third party not involved in the testing.
• Purpose: OTHER
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: February 20, 2024
• First Posted: April 5, 2024
• Study Start: February 20, 2024
• Primary Completion: May 31, 2024
• Study Completion: May 31, 2024
• Last Updated: April 13, 2025

Record last verified: 2025-04

Data Sharing

• IPD Sharing: Will share
• Shared Documents: ANALYTIC CODE
• Time Frame: Upon publication - permanent repository
• Access Criteria: Public repository - exact web address available upon publication.

Locations

SG (1)