Acute Effects of Beetroot Juice on Isometric Knee Extension Strength, Explosive Strength and Local Muscular Endurance

Acute Effects of Beetroot Juice Ingestion on Isometric Knee Extension Strength, Explosive Strength and Local Muscular Endurance

This is a double-blind placebo-controlled cross-over trial that aims to determine the acute effect of beetroot juice ingestion on isometric knee extension strength, explosive strength and local muscular endurance.

Study Overview

• Status: Completed
• Conditions: Healthy Adults
• Intervention / Treatment: Dietary supplement: Beetroot juice concentrate (140 ml); Dietary supplement: Blackcurrant juice (placebo)

Detailed Description

The study aims to determine whether concentrated beetroot juice has an acute effect on isometric strength of the knee muscles and the rate of force development in knee extension, as well as endurance of the same muscle. This will be a cross-over study. 20 subjects will be randomly selected to the experimental group or control group; after 1 week, participants will repeat the measurements in the other condition. Subjects will consume 140 ml of beetroot juice extract 2.5 hours before the measurement or placebo (140 ml of blackcurrant juice with added appropriate amount of sugar to equalize the carbohydrate value and lemon juice fort the taste). An isometric dynamometer will be used to measure the isometric strength of the knee extensors. Investigators will quantify peak force, rate of force development, endurance of knee extensors at 50 % of the maximal force, and the force recovery after a fatiguing protocol.

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Slovenia
  • Izola, Slovenia, SI-6310
    • University Of Primorska Faculty of Health Sciences

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 30 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age between 18 and 30 years
• Physically active and healthy athletes (recreational or professional)

Exclusion Criteria:

• Cardiovascular, pulmonary, metabolic, neurological diseases and musculoskeletal injuries
• Smokers
• Consumption of drugs such as antacids and proton pump inhibitors in the previous 3 months
• Pregnant or breastfeeding women
• Beetroot allergic participants

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Experimental condition, receiving beetroot juice supplement; Participants will receive beetroot juice intervention in the experimental condition.	Dietary supplement: Beetroot juice concentrate (140 ml); A beetroot juice concentrate (140 ml) will be administered to participants in experimental conditions.
Placebo Comparator: Placebo condition; Participants will receive placebo (blackcurrant juice) in the placebo condition	Dietary supplement: Blackcurrant juice (placebo); 140 ml of blackcurrant juice with added appropriate amount of sugar to equalize the carbohydrate value and lemon juice fort the taste.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Knee extension strength	The peak force during maximal voluntary contraction of knee extensors	2 hours after the ingestion of beetroot juice or placebo

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Knee extension explosive strength	The rate of force development during maximal voluntary contraction of knee extensors	2 hours after the ingestion of beetroot juice or placebo
Knee extension local muscle endurance	Time to failure of knee muscles at 50 % of maximal force	2 hours after the ingestion of beetroot juice or placebo

Collaborators and Investigators

• Sponsor: University of Primorska

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2022
• Primary Completion (Actual): October 15, 2022
• Study Completion (Actual): October 17, 2022

Study Registration Dates

• First Submitted: October 2, 2022
• First Submitted That Met QC Criteria: October 2, 2022
• First Posted (Actual): October 5, 2022

Study Record Updates

• Last Update Posted (Actual): October 19, 2022
• Last Update Submitted That Met QC Criteria: October 17, 2022
• Last Verified: October 1, 2022

More Information

Terms related to this study

• Keywords: supplementation; isometric strength; beetroot; nitrates; local muscle endurance
• Other Study ID Numbers: BEETROOT

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Undecided

Drug and device information, study documents

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