Long-Term Effect of Combined Citrulline and Nitrate-Rich Beetroot Extract Supplementation
- Conditions
- AthletesCitrullineNitrate
- Interventions
- Dietary Supplement: CitrullineDietary Supplement: Nitrate plus CitrullineDietary Supplement: PlaceboDietary Supplement: Nitrate
- Registration Number
- NCT05143879
- Lead Sponsor
- Burgos Nutrition
- Brief Summary
Citrulline (CIT) and nitrate-rich beetroot extract (BEET) are widely studied ergogenic aids. However, both supplements have been studied in sort-term and isolated. To the best of the authors' knowledge, the effects of combining both supplements on exercise-induced muscle damage (EIMD) and hormone status have not been investigated to date. Therefore, the main purpose of this study was to determine the effect and degree of potentiation of the long-term (9 weeks) mixture of 3 g/day of CIT plus 2.1 g/day of BEET (300 mg/day of NIT) supplementation on EIMD markers (urea, creatinine, AST, ALT, GGT, LDH and CK) and anabolic/catabolic hormone status (testosterone, cortisol and Testosterone cortisol ratio (T/C)) in male trained triathletes. This study was a double-blind, placebo-controlled trial where participants (n = 32) were randomized into 4 different groups: placebo group (PLG; n = 8), CIT group (CITG; 3 g/day of CIT; n = 8), BEET group (BEETG; 2.1 g/day of BEET (300 mg/day of NIT) ; n = 8) and CIT-NIT group (CIT-BEETG; 3 g/day of CIT plus 2.1 g/day of BEET (300 mg/day of NIT); n = 8). Blood samples were collected from all participants at baseline (T1) and after 9 weeks of supplementation (T2).
- Detailed Description
Triathlon is an endurance sport in which athletes compete sequentially in swimming, cycling and running. Prolonged and strenuous training combined with insufficient recovery can produce muscular and metabolic stress, resulting in structural and functional damage to the musculoskeletal system leading to a fatigue status, which results in decreased athletic performance. As a consequence of this type of combined exercise, there are also alterations in biochemical markers of exercise-induced muscle damage (EIMD) as well as anabolic/catabolic hormones. Therefore, their analysis is useful in determining the balance between training loads and recovery. In this sense, it is essential to include different strategies to reduce or prevent EIMD, which delay or reduce muscle fatigue and improve sports performance. One of these strategies is the use of different ergogenic aids such as L-citrulline (CIT) and nitrates (NIT) which have been proposed as both substances produce an increase in nitric oxide (NO).
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- Male
- Target Recruitment
- 32
- Males between 25 and 35 years old
- Triathletes
- With at least 5 years of experience
- Without any disease
- Non smokers
- Non drinkers of alcohol
- Not to take any other medications or stimulant substances during the study
- 2 weeks without taking other nutritional supplements
- Exclusion criteria:
- Men under 25 and over 35 years of age.
- Non triathletes
- Less than 5 years of experience
- With any disease
- Smokers
- Alcohol drinkers
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description Citrulline Citrulline 8 subjects took 3 g/kg/day of citrulline during 9 weeks Nitrate plus Citrulline Nitrate plus Citrulline 8 subjects took 3 g/kg/day of nitrate plus citrulline during 9 weeks Placebo Placebo 8 subjects took 3 g/kg/day of placebo during 9 weeks Nitrate Nitrate 8 subjects took 3 g/kg/day of nitrate during 9 weeks
- Primary Outcome Measures
Name Time Method Testosterone to cortisol ratio 9 weeks ng/mL
ALT 9 weeks U/L
Testosterone 9 weeks ng/mL
Urea 9 weeks mg/dl
AST 9 weeks U/L
GGT 9 weeks U/L
LDH 9 weeks U/L
CK 9 weeks U/L
Cortisol 9 weeks μg/dL
Creatinine 9 weeks mg/dl
- Secondary Outcome Measures
Name Time Method
Trial Locations
- Locations (1)
University of Leon
🇪🇸León, Castilla Y León, Spain
University of Leon🇪🇸León, Castilla Y León, Spain