Impact of Caffeine Intake on Autonomic Parameters in the Exercise of Strength

NCT ID: NCT03899675

Last Updated: 2019-04-18

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 30 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2018-12-19
• Study Completion Date: 2019-03-20

Brief Summary

The objective of this study was to evaluate the variability of the heart rate of exercise physicists with and without caffeine intake. Practitioners of resisted physical exercise, specifically bodybuilding, who are young adults between the ages of 18 and 30 will participate in the study. To define the sample size, a sample calculation was performed based considering as variable the RMSSD index (square root of the square mean of the differences between the adjacent normal iRRs). The significant difference magnitude assumed was 12 ms, considering a standard deviation of 16.2 ms, with alpha risk of 5% and beta of 80%. A minimum of 14 subjects per group were required in the survey. A total of 32 subjects will participate in the research, being these divided and allocated in different groups. Sampling will be of the intentional kind.

Detailed Description

Caffeine supplementation has been studied in several sports modalities with the objective of investigating its repercussions on athletes' physical performance. Caffeine may lead to an obstruction of adenosine receptors (A1 and A2) and increase the activity of the Autonomic Nervous System (ANS) by releasing catecholamines in plasma, inducing tachycardia and elevating blood pressure. Such modulation of nervous system activity can be traced by assessing heart rate variability (HRV). HRV is one of the most practical methods to analyze the physiological functioning of ANS, both in pathological conditions of the individual and in the induction of other variables, being a noninvasive measure of cardiac autonomic modulation markers that analyzes the peak-R intervals a peak-R (RRI) of consecutive heartbeat. The objective of this study was to evaluate the variability of the heart rate of exercise physicists with and without caffeine intake. Practitioners of resisted physical exercise, specifically bodybuilding, who are young adults between the ages of 18 and 30 will participate in the study. To define the sample size, a sample calculation was performed based considering as variable the RMSSD index (square root of the square mean of the differences between the adjacent normal iRRs). The significant difference magnitude assumed was 12 ms, considering a standard deviation of 16.2 ms, with alpha risk of 5% and beta of 80%. A minimum of 14 subjects per group were required in the survey. A total of 32 subjects will participate in the research, being these divided and allocated in different groups. Sampling will be of the intentional kind.

The expected benefits with the result of this research are to instigate the creation of new lines of research in this context, being able to intervene in a more effective way in practitioners of physical exercise of strength, with the possibility of prevention to the autonomic alterations that are associated with the consumption of stimulant supplements, such as caffeine, and its consequences on the cardiovascular system.

Conditions

Autonomic Nervous System; Cardiovascular Outcomes

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: PREVENTION
• Blinding Strategy: SINGLE

Study Groups

Caffeine

Volunteers will ingest 300mg caffeine one hour before strength training.

Group Type: EXPERIMENTAL

Caffeine

Intervention Type: OTHER

On the first day of collection, the volunteers will not take caffeine intake, the data will be collected in a standardized way, respecting the times defined for the analysis of the cardiac activity. Then the collection will be continued. On the next day of evaluation, volunteers will receive a capsule containing 300 mg of caffeine and will be advised to consume 1 hour before the procedure.

Placebo

Volunteers will ingest 300mg placebo one hour before strength training.

Group Type: PLACEBO_COMPARATOR

Placebo

Intervention Type: DIETARY_SUPPLEMENT

On the first day of collection, the volunteers will not take placebo intake, the data will be collected in a standardized way, respecting the times defined for the analysis of the cardiac activity. Then the collection will be continued. On the next day of evaluation, volunteers will receive a capsule containing 300 mg of placebo and will be advised to consume 1 hour before the procedure.

Interventions

Placebo

On the first day of collection, the volunteers will not take placebo intake, the data will be collected in a standardized way, respecting the times defined for the analysis of the cardiac activity. Then the collection will be continued. On the next day of evaluation, volunteers will receive a capsule containing 300 mg of placebo and will be advised to consume 1 hour before the procedure.

Intervention Type: DIETARY_SUPPLEMENT

Caffeine

On the first day of collection, the volunteers will not take caffeine intake, the data will be collected in a standardized way, respecting the times defined for the analysis of the cardiac activity. Then the collection will be continued. On the next day of evaluation, volunteers will receive a capsule containing 300 mg of caffeine and will be advised to consume 1 hour before the procedure.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Male
• 18 to 30 years of age
• Body Mass Index (BMI) within the range of Eutrophy (18.5 to 24.9kg / m²)
• Experience with resistance training, uninterrupted for at least 3 months and weekly frequency of 3 sessions or more
• Do not use any medication that may interfere with cardiac autonomic modulation
• Do have no skeletal muscle damage.

Exclusion Criteria

• Smoking patients
• As well as individuals who have already used anabolic steroids
• Cardiorespiratory diseases
• Cardiometabolic diseases
• Neurological disorders
• Other known compromises that prevent the subject from performing the procedures.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 30 Years
• Eligible Sex: MALE
• Accepts Healthy Volunteers: Yes

Sponsors

University of Pernambuco

OTHER

Sponsor Role: lead

Responsible Party

Cicero Jonas Rodrigues Benjamim

Principal Investigator

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

Cicero Jonas Rodrigues Benjamim

Juazeiro do Norte, Ceará, Brazil

Countries

Brazil

Other Identifiers

UPernambuco

Identifier Type: -

Identifier Source: org_study_id