Effects of Beet Juice and Diet in Female Rowers

The Effects of Beetroot Supplementation and Habitual Dietary Nitrate Intake on Exercise Performance in Collegiate Female Rowing Athletes

The purpose of this study is to determine the effects of nitrate-rich beetroot juice supplementation on exercise performance in female rowers when accounting for habitual vegetable nitrate consumption.

Study Overview

• Status: Completed
• Conditions: Exercise; Dietary Habits; Nitrates
• Intervention / Treatment: Dietary supplement: Placebo; Dietary supplement: Beet Juice

Detailed Description

The objective is to use a stratified block randomization, double-blind crossover trial to test rowing ergometer exercise performance after drinking a beetroot juice supplement and compare it to the same test after consuming a placebo (a nitrate-free version of the beetroot juice supplement) in a convenience sample of athletes from a single Division 1-A collegiate women's rowing team.

Before testing, the participants' habitual vegetable nitrate consumption will be assessed from their report of foods consumed in the past 24 hours. Estimates of dietary nitrate intake will be calculated from the quantity of vegetables consumed and used to determine whether dietary nitrate intake influences the efficacy of the beetroot juice supplement.

• Study Type: Interventional
• Enrollment (Actual): 15
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Kansas
    • Lawrence, Kansas, United States, 66044
      • University of Kansas Rowing Boathouse

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Healthy
• Athletes currently on the university's rowing team

Exclusion Criteria:

• Injuries or medical conditions that prevent participation in their team's rowing training program
• Diagnosis of stage 2 iron deficiency
• Unable to consume beet juice for any reason

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Standard Beet Juice First; First Test: Beet Juice / Second Test: Placebo	Dietary supplement: Placebo; 70mL placebo Beet Juice (Beet It Sport Shot with nitrate removed) consumed 2.5 hours before exercise test; Dietary supplement: Beet Juice; 70 milliliter (70mL) standard Beet Juice (Beet It Sport Shot) consumed 2.5 hours before exercise test
Experimental: Placebo Beet Juice First; First Test: Placebo / Second Test: Beet Juice	Dietary supplement: Placebo; 70mL placebo Beet Juice (Beet It Sport Shot with nitrate removed) consumed 2.5 hours before exercise test; Dietary supplement: Beet Juice; 70 milliliter (70mL) standard Beet Juice (Beet It Sport Shot) consumed 2.5 hours before exercise test

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Rowing Test Time	Time (seconds) to complete 500-meter rowing time trial tests.	Recorded immediately upon completion of each of the 4 500-meter intervals during rowing time trial tests on day 7 and day 14.
Rowing Test Perceived Exertion	Rating of perceived exertion reported by participant during rowing time trial tests. The Borg Scale is used, in which participants choose a number between 6 ("Rest") and 20 ("Maximal Effort") to indicate their perceived exertion at the completion of each 500-meter segment.	Recorded immediately upon completion of each of the 4 500-meter intervals during rowing time trial tests on day 7 and day 14.
Rowing Test Peak Heart Rate	Maximum heart rate (beats per minute) during 500-meter rowing time trial tests. The Maximum is the single highest heart rate recorded during that 500-meter interval.	Recorded during each of the 4 500-meter intervals during rowing time trial tests on day 7 and day 14.
Rowing Test Average Heart Rate	Mean heart rate (beets per minute) during 500-meter rowing time trial tests.	Recorded during each of the 4 500-meter intervals during rowing time trial tests on day 7 and day 14.
Rowing Test Peak Power Output	Maximum power (watts) during 500-meter rowing time trial tests	Recorded during each of the 4 500-meter intervals during rowing time trial tests on day 7 and day 14.
Rowing Test Average Power Output	Mean power (watts) during 500-meter rowing time trial tests	Recorded during each of the 4 500-meter intervals during rowing time trial tests on day 7 and day 14.
Dietary Nitrate Habitual Consumption Amount	Mean vegetable nitrate consumption (mg/day) from two different self-administered 24-hour dietary recalls (ASA24).	Collected after each rowing time trial test for the preceding 24-hour period (day 6 and day 13). Means determined in post-testing analysis.
Dietary Nitrate Habitual Consumption Category	Categorization of Dietary Nitrate Habitual Consumption Amount. The median of all participants' Amounts will be determined to categorize each participant as "high" (above median) or "low (below median).	Collected after each rowing time trial test for the preceding 24-hour period (day 6 and day 13). Median and categories determined in post-testing analysis.

Collaborators and Investigators

• Sponsor: University of Kansas Medical Center
• Investigators: Principal Investigator: Jessica A Provost, MS, University of Kansas Medical Center

Study record dates

Study Major Dates

• Study Start (Actual): October 3, 2023
• Primary Completion (Actual): November 17, 2023
• Study Completion (Actual): December 31, 2023

Study Registration Dates

• First Submitted: September 13, 2023
• First Submitted That Met QC Criteria: September 13, 2023
• First Posted (Actual): September 21, 2023

Study Record Updates

• Last Update Posted (Estimated): February 2, 2024
• Last Update Submitted That Met QC Criteria: January 31, 2024
• Last Verified: January 1, 2024

More Information

Terms related to this study

• Keywords: exercise; sex differences; muscle; performance; dietary nitrate; beetroot juice
• Other Study ID Numbers: STUDY00150492

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Upon completion of the testing protocol, all data analysis will be conducted using only using the de-identified participant identification numbers. There is no plan to share individual participant data with other researchers.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No