Beetroot Juice, Beetroot Juice with Caffeine Co-ingestion, Caffeine, Placebo
Conditions
Keywords
beetroot juice, nitrate, caffeine, resistance training, dietary supplement, female
Brief summary
The aim of this study is to evaluate the acute effects of beetroot juice and caffeine, consumed individually or in combination, on lower-limb strength and muscular endurance in physically active women. The main questions it aims to answer are: * Does the co-ingestion of beetroot juice and caffeine enhance lower-limb strength and muscular endurance more than either substance alone or a placebo? * How do the acute effects of beetroot juice interact with caffeine on physical performance? The study was conducted using a randomized, crossover design to evaluate the following four conditions: Beetroot juice with placebo Caffeine with placebo Beetroot juice with caffeine Placebo only Each participant completed all conditions, with a sufficient washout period between sessions to eliminate potential carryover effects. This design allowed for a direct comparison of the acute effects of each supplementation strategy on lower-limb strength and muscular endurance. Participant Protocol Participants consumed their assigned supplement on a single testing day for each condition. After supplementation, they performed standardized tests to measure lower-limb strength and muscular endurance. Progress was monitored, and data from all conditions were collected to assess the acute effects of each intervention.
Interventions
DIETARY_SUPPLEMENTBeetroot juice combined with caffeine (COM)
* 70 mL of beetroot juice (400 mg NO3-, BEET It Sport; James White Drinks Ltd) 120 minutes before experimental session * 200 mg caffeine capsule from the IO.GENIX Nutrition brand (Toledo, Spain) 60 minutes before experimental session
DIETARY_SUPPLEMENTBeetroot juice placebo with caffeine (CAF)
\- 70 mL of a blackcurrant beverage, which depletes NO3- (Capri-Sun) 120 minutes before experimental session - 200 mg caffeine capsule from the IO.GENIX Nutrition brand (Toledo, Spain) 60 minutes before experimental session
DIETARY_SUPPLEMENTBeetroot juice with caffeine placebo (BRJ)
\- 70 mL of beetroot juice (400 mg NO3-, BEET It Sport; James White Drinks Ltd) 120 minutes before experimental session - Multivitamin capsule from NaturrTierra (Leganés, Spain) 60 minutes before experimental session
OTHERBeetroot placebo with caffeine placebo (PLA)
\- 70 mL of a blackcurrant beverage, which depletes NO3- (Capri-Sun) 120 minutes before experimental session - Multivitamin capsule from NaturrTierra (Leganés, Spain) 60 minutes before experimental session
Sponsors
Jose Manuel Jurado Castro
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
OTHER
Masking
DOUBLE (Subject, Investigator)
Intervention model description
Double-Blind Crossover Randomized Trial
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 35 Years
Healthy volunteers
Yes
Inclusion criteria
* Minimal experience of six months of strength training * Be familiarized with the exercise test: counter movement jump (CMJ), barbell back squats, leg press and knee extension.
Exclusion criteria
* Supplementation consumption * Sports injuries
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change of height reached in jump | Visit 1 (Day 1), Visit 2 (Day 5), Visit 3 (Day 9), Visit 4 (Day 13) | Evaluated through Countermovement jump test with a recovery period of 45 seconds between jumps. The height reached was recorded in centimeters. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Movement velocity | Visit 1 (Day 1), Visit 2 (Day 5), Visit 3 (Day 9), Visit 4 (Day 13) | The velocity was recorded in meters per second (m/s) during two repetitions of the back squat, evaluated at 50% and 75% of the repetition maximum (RM). |
| Muscular endurance test | Visit 1 (Day 1), Visit 2 (Day 5), Visit 3 (Day 9), Visit 4 (Day 13) | 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 (3 series). The number of repetitions was recorded. |
| Rating of perceived exertion (RPE). | Visit 1 (Day 1), Visit 2 (Day 5), Visit 3 (Day 9), Visit 4 (Day 13) | 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). |
Countries
Spain
Outcome results
None listed