Heart Rate RecoveryNCT03380195
Effects of Watermelon Juice on Heart Rate Recovery and Post-exercise Muscle Soreness
A study testing Watermelon juice, Sport drink and Sugar water in people with Heart Rate Recovery, run by San Diego State University at 1 site in United States.
Trial summary
The purpose of this study was to determine the effects of a pre-exercise, single practical dose of watermelon juice, Gatorade, sugar water or water on heart rate recovery, blood lactate levels, and 24-hour post exercise muscle soreness. Read more about this study
- Who is it for?
- Ages 21 to 50 yearsHealthy volunteers can take part
- Conditions the study is for
- Heart Rate Recovery
- What is being tested?
- Watermelon juice, Sport drink and Sugar water
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 27 participants
- Where
- 1 siteUnited States
- Study dates
- 1 Sep 2016to Dec 2028
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 21 to 50 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- ages of 21-50 healthy adults
Who cannot join
- Suffering from injury
- Chronic inflammatory conditions
- Required dietary supplement use
- Required medication which affects blood pressure
- Smoking
- Pregnant woman
- Allergy to watermelon
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
Exercise and Nutritional Sciences, SDSU
San Diego, California, 92182-7251
Mee Young Hong, 619-594-2392, mhong2@mail.sdsu.edu
About this study
The purpose of this study was to determine the effects of a pre-exercise, single practical dose of watermelon juice, Gatorade, sugar water or water on heart rate recovery, blood lactate levels, and 24-hour post exercise muscle soreness.
- Conditions
- Heart Rate Recovery
- Being tested
- Watermelon juice, Sport drink, Sugar water, Water
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Watermelon juiceOther
Subject drinks 355ml of watermelon juice 1 hour prior to submaximal exercise
Sport drinkOther
Subject drinks 355ml of Gatorade 1 hour prior to submaximal exercise
Sugar waterOther
Subject drinks 355ml of sugar water (22.5g) 1 hour prior to submaximal exercise
WaterOther
Subject drinks 355ml of water 1 hour prior to submaximal exercise
| Study group | Role | What they receive |
|---|---|---|
| Watermelon juice | Experimental | Not described Receives: Other: Watermelon juice |
| Sport drink | Active comparator | Not described Receives: Other: Sport drink |
| Sugar water | Active comparator | Not described Receives: Other: Sugar water |
| Water | Placebo comparator | Not described Receives: Other: Water |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change of heart rate after submax exercise
The participants then were fitted to cycling shoes and familiarized with the Lode cycle ergometer (Lode Excalibur Sport, Groningen, Netherlands), completed a warm-up and were asked to perform a criterion work rate trial ending at 80% predicted HRmax. Heart rate was recorded every minute post exercise for a maximum of 20 minutes post exercise.
Measured: Baseline and every minute post exercise for a maximum 20 minutes post exercise.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted21 Dec 2017
- Study start1 Sep 2016
- Primary completionDec 2028 (estimated)
- Study completionDec 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Heart Rate RecoveryStudies of the same condition, open and under way.
- More trials run by San Diego State UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Enrolment
- 27 participants (estimated)
Sponsor and investigators
- Lead sponsor
- San Diego State University
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03380195
- Sponsor's protocol ID
- 2487100
- Status last verified
- Jan 2026
- First submitted
- 11 Dec 2017
- Last updated
- 21 Jan 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 21 Jan 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effects of Watermelon Juice on Heart Rate Recovery and Post-exercise Muscle Soreness
- ClinicalTrials.gov ID
- NCT03380195
- Acronym / sponsor ID
- 2487100
- Conditions
- Heart Rate Recovery
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 27 participants (estimated)
- Lead sponsor
- San Diego State UniversityUniversity, hospital or other
- Study start
- 1 Sep 2016 (actual)
- Primary completion
- Dec 2028 (estimated)
- Study completion
- Dec 2028 (estimated)
- First posted
- 21 Dec 2017 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this study was to determine the effects of a pre-exercise, single practical dose of watermelon juice, Gatorade, sugar water or water on heart rate recovery, blood lactate levels, and 24-hour post exercise muscle soreness.
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Number of arms
- 4
| Arm | Type | Receives |
|---|---|---|
| Watermelon juice | Experimental | Other: Watermelon juice |
| Sport drink | Active comparator | Other: Sport drink |
| Sugar water | Active comparator | Other: Sugar water |
| Water | Placebo comparator | Other: Water |
Who may qualify
- Ages
- 21 to 50 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (1 listed)
- ages of 21-50 healthy adults
Key exclusion criteria (7 listed)
- Suffering from injury
- Chronic inflammatory conditions
- Required dietary supplement use
- Required medication which affects blood pressure
- Smoking
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Watermelon juiceSubject drinks 355ml of watermelon juice 1 hour prior to submaximal exercise | Other | Watermelon juice |
| Sport drinkSubject drinks 355ml of Gatorade 1 hour prior to submaximal exercise | Other | Sport drink |
| Sugar waterSubject drinks 355ml of sugar water (22.5g) 1 hour prior to submaximal exercise | Other | Sugar water |
| WaterSubject drinks 355ml of water 1 hour prior to submaximal exercise | Other | Water |
Primary outcome
Change of heart rate after submax exercise
Time frame: Baseline and every minute post exercise for a maximum 20 minutes post exercise.
The participants then were fitted to cycling shoes and familiarized with the Lode cycle ergometer (Lode Excalibur Sport, Groningen, Netherlands), completed a warm-up and were asked to perform a criterion work rate trial ending at 80% predicted HRmax. Heart rate was recorded every minute post exercise for a maximum of 20 minutes post exercise.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 21 Jan 2026.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Watermelon juice, Sport drink and Sugar water in people with Heart Rate Recovery, run by San Diego State University at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 21 Jan 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Mee Young Hong (619-594-2392, mhong2@mail.sdsu.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change of heart rate after submax exercise (time frame: Baseline and every minute post exercise for a maximum 20 minutes post exercise.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 21 Jan 2026.