Clinical trial NCT05143879: Long-Term Effect of Combined Citrulline and Nitrate-Rich Beetroot Extract Supplementation
Official title: Long-term Effect of Combined Citrulline and Nitrate-rich Beetroot Extract Supplementation on Recovery Status in Trained Male Triathletes
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Citrulline
Nitrate
Athletes
Keywords: triathlon
performance
ergogenic aids
muscle fatigue
recovery
hormones
Lead sponsor: Burgos Nutrition
Sponsor class: OTHER
Collaborators: name: Universidad de León
name: University of the Basque Country (UPV/EHU)
name: University of Valladolid
First posted: 2021-12-03
Enrollment: 32
Sex: MALE
Minimum age (years): 25
Maximum age (years): 35
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: 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 CM 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 (T), cortisol (C), and T/C) in male trained triathletes.
Primary purpose: OTHER

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).

Eligibility criteria: Inclusion Criteria:

* 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:

* 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

Primary outcomes:
measure: Cortisol
timeFrame: 9 weeks
measure: Testosterone
timeFrame: 9 weeks
measure: Testosterone to cortisol ratio
timeFrame: 9 weeks
measure: Urea
timeFrame: 9 weeks
measure: Creatinine
timeFrame: 9 weeks
measure: AST
timeFrame: 9 weeks
measure: ALT
timeFrame: 9 weeks
measure: GGT
timeFrame: 9 weeks
measure: LDH
timeFrame: 9 weeks
measure: CK
timeFrame: 9 weeks
Secondary outcomes:
Other outcomes:
Locations:
city: León
country: Spain
facility: University of Leon
state: Castilla Y León
Study officials:
affiliation: University of Leon
name: Jose Burgos Balmaseda, Graduate
role: PRINCIPAL_INVESTIGATOR
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