Effect of Beetroot Juice Supplements on Lower-limb Strength in Females

Study Overview
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Brief Summary
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This study aims to evaluate the effects of beetroot juice supplements on lower-limb strength and muscular endurance in physically active women, due to the presence of NO3- in beetroot juice.

Detailed Description
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Beetroot juice (BJR) is used as an ergogenic aid, but no study has analyzed its' effects on explosive force production in physically active women. It has been proposed that females could blunt reduction of NO2- to NO based on a higher oxidative skeletal muscle phenotype than males. However, it has been observed a higher increase on plasma NO2- levels after supplementation compared to and a greater enhancement on muscle contractile function. Based on the absence of any study that has analyzed the effect of NO3- supplements on jump ability and power production on weightlifting on female population; the purpose of this study will be to investigate the possible ergogenic effect of BJR on physically active women on explosive force production and muscular endurance in a lower-limb body weightlifting protocol, due to the presence of NO3- in BJR and its effects.

Official Title
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Acute Effects of Beetroot Juice Supplements on Lower-limb Strength and Muscular Endurance in Physically Active Women: Double-blind Crossover Randomized Trial

Conditions
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Muscular Endurance

Intervention / Treatment
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* Dietary Supplement: Beetroot juice
* Other: Capri-Sun


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Physically active females with 18-30 years of age More than 6 months on RT training programs Be familiarized with back squat, leg press and leg extension exercises Not consuming any type of nutritional supplement or anabolic substances in the previous three months or during the study Not suffering from a musculoskeletal injury that could interfere with the exercise protocol during the investigation Exclusion Criteria: None

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 30 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: The experimental procedure will consist of three visits, separate from each other by one week, to achieve the total elimination of any effects caused by BJR as well as the optimal recovery of the participants.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: BJR<br>70 mL of beetroot juice (BEET It Sport®; James White Drinks Ltd., Ipswich, UK) | Dietary Supplement: Beetroot juice<br>* Subjects will drink juice 120 minutes before each visit<br>|
| Placebo Comparator: PLA<br>70 mL of blackcurrant beverage Capri-Sun. | Other: Capri-Sun<br>* 70 mL of blackcurrant beverage, which is depleted of NO3- will be taken 120 min before each visit.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of height reached in jump | Evaluated through CMJ (Counter movement jump) test with a recovery period of 45 seconds between jumps. | Week 1, 2 and 3. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Movement velocity | Evaluated at 50% and 75% repetition maximum (RM) | Visit 1 (week 1), 2 (week 2) and 3 (week 3). | 
| Power on back squat | Evaluated at 50% and 75% repetition maximum (RM) | Visit 1 (week 1), 2 (week 2) and 3 (week 3). | 
| Muscular endurance test | The test consists of three exercises: back squat, leg press and leg extension. Three series will be performed until concentric failure at 75% RM, three minutes of rest between each series. | Visit 1 (week 1), 2 (week 2) and 3 (week 3). | 
| Rating of perceived exertion (RPE). | Immediately at the end of the muscular endurance test, participants will be instructed to report their RPE using a scale 1-10 (worse to better outcome). | Visit 1 (week 1), 2 (week 2) and 3 (week 3). | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Explosive force production, Beetroot juice, Beetroot, muscular endurance