Acute Effects of Beet Extract on Autonomic and Cardiovascular Recovery After Exercise
Condition: Cardiovascular Diseases; Prevention
MeSH terms: Cardiovascular Diseases
Study type: Interventional

Summary: 
      Dietary NO3 is found in high concentrations in green leafy vegetables and beets. Studies
      weighing the action of NO3 for ergogenic purposes have found metabolic improvement in
      skeletal muscle during exercise in hypoxia, lowering blood pressure and increased workload at
      anaerobic threshold. In a way, the use of nitrate in combination with exercise may assist in
      autonomic adaptation to multiple stimuli, such as rest, during exercise and during the
      recovery period. HRV is one of the most practical methods for analyzing the physiological
      functioning of the ANS, both in the pathological condition of the individual and in the
      induction of other variables. peak-R (RRI) of consecutive heart beats. This study aims to
      evaluate the effect of beet extract supplementation in combination with submaximal strength
      exercise on heart rate variability and cardiovascular parameters of physically active
      individuals. It is a double-blind randomized crossover clinical trial.
    

Detailed description: 
      An anamnesis of the participants will be made before the research. Essential information such
      as name, gender, age, height, BMI will be collected. Anthropometric measurements will be
      acquired according to the recommendations. Volunteers will be properly informed about the
      procedures and objectives of this study.

      From a pre-established randomization, on the first day of collection volunteers will be
      allocated to group I (Placebo) or group II (Beet Extract). In the first intervention the
      volunteers allocated in group I will take a capsule containing 600mg of starch, at the end of
      this will be provided another capsule containing 600mg of beet extract for the second
      intervention. Conversely, group II volunteers will ingest a capsule containing 600mg of beet
      extract in the first intervention, and at the end of the experiment, another capsule
      containing 600mg of starch will be provided.

      Research participants will be advised to consume the capsules within 2 hours of the
      procedure, adequate time for digestion, absorption and effect on the body. Prior to testing
      will be asked about the use of caffeine or any other type of substance that is described in
      the study inclusion and exclusion criteria. Then the collection will proceed.

      Participants' blood pressure will be measured before (Rest) and after submaximal strength
      exercise during the first recovery time (REC1- 00-05 minutes) at 5 1-minute intervals using
      an aneroid sphygmomanometer (Premium®). and stethoscope (Rappaport®). Korotkoff's first and
      fifth phase readings were adopted as systolic and diastolic blood pressure, respectively.

      Resistance exercise will be performed by performing movements that recruit lower limbs,
      emphasizing the quadriceps, posterior leg and buttocks. Training intensity will be defined by
      a subjective test of 1 repetition maximum (1RM). The evaluation will take place at a time
      before (at least 72 hours) to the data collection, aiming to pre-define and standardize the
      load that will be used on the day of the experiment. In this sense, the individuals will be
      oriented to test the load in the 4 proposed physical exercises in a total of 10 maximum
      repetitions, obtaining 75% of 1 maximum repetition (75% 1RM).

      Leg Press 45º - 4 sets x 10 repetitions (75% 1RM) Extender Chair - 4 sets x 10 reps (75% 1RM)
      Abductor Chair - 4 sets x 10 repetitions (75% 1RM) Guided Squat - 4 sets x 10 repetitions
      (75% 1RM
    

Intervention name(s): Beetroot extract; Placebo
Intervention type(s): Dietary Supplement; Other
Intervention description(s): Ingestion of 600mg beetroot extract two hours before strength exercise (75% 1RM).; Ingestion of 600mg starch two hours before strength exercise (75% 1RM).
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Prevention
Keywords: Beetroot; Heart rate variability; Blood pressure; Strenght Exercise