Acute Caffeine Effects on Cardiac Autonomic and Cardiorespiratory Parameters Responses After Aerobic Exercise

Study Overview
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Brief Summary
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Check the acute influence of caffeine on the autonomic modulation and cardiorespiratory parameters after aerobic exercise. Hypothesized that caffeine can promote a slower recovery of the cardiorespiratory parameters and the SNA recovery after aerobic exercise.

Detailed Description
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The experimental procedure is divided into three phases, all performed on a treadmill, with a minimum interval of 48 hours between them, in order to allow adequate recovery of the participants. Before the start of the first stage of the experimental protocol or control anthropometric measurements will be carried out, body weight by a digital scale (Plenna, TIN 00139 MAXIMA, Brazil)) and then, using a stadiometer (Plenna, TIN 00139 MAXIMA, Brazil)). The protocols are: I) Maximum stress test protocol: assessment of the maximum oxygen consumption (VO2max) on a treadmill (Inbrasport / Millennium), using the Bruce protocol. II) Control Protocol (PC): at this stage the volunteer will ingest compressed form of placebo similar to Protocol III and remained at rest after 15 minutes in the supine position, followed by 30 minutes of aerobic exercise on a treadmill, 5 minutes with speed 6.0 km / h followed by 25 minutes with 60% of VO2max and the final 60 minutes lying recovery. III) Experimental protocol (PE): In this stage, the volunteer had performed activities similar to the PC, but will make the tablet intake consists of 300mg of caffeine, a value that is within the maximum daily amount allowed under the FDA.

Official Title
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Acute Caffeine Effects on Cardiac Autonomic and Cardiorespiratory Parameters Responses After Aerobic Exercise

Conditions
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Autonomic Nervous System, Cardiorespiratory Parameters

Intervention / Treatment
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* Drug: Caffeine
* Drug: Placebo
* Other: Cardiopulmonary test
* Other: Treadmill aerobic exercise


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: healthy men. Exclusion Criteria: cardiovascular, orthopedic, respiratory and neurological disorders reported or other pathological conditions that prevent the subject to perform the protocols; smokers, alcoholics, or who use drugs that influence the activity of the heart.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 30 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Caffeine protocol<br>300 mg in pills | Drug: Caffeine<br>* Volunteers will consume 300 mg of caffeine in pills fifteen minutes before treadmill aerobic exercise.<br>Other: Cardiopulmonary test<br>* assessment of the maximum oxygen consumption (VO2max) on a treadmill (Inbrasport / Millennium), using Buce protocol. .<br>Other: Treadmill aerobic exercise<br>* 30 mim of aerobic exercise (5 minutes at speed of 5.0 km/h for warming-up followed by 25 minutes at 60% of VO2max ).<br>|
| Experimental: Placebo protocol<br>300 mg in pills | Drug: Placebo<br>* Volunteers will consume 300 mg of placebo in pills fifteen minutes before treadmill aerobic exercise.<br>Other: Cardiopulmonary test<br>* assessment of the maximum oxygen consumption (VO2max) on a treadmill (Inbrasport / Millennium), using Buce protocol. .<br>Other: Treadmill aerobic exercise<br>* 30 mim of aerobic exercise (5 minutes at speed of 5.0 km/h for warming-up followed by 25 minutes at 60% of VO2max ).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Caffeine effects on heart rate variability (based on frequency, time domain and Chaos) |  | up to 1 year | 
| Blood pressure (mmHg) | Caffeine effects blood pressure recovery following aerobic exercise | up to 1 year | 
| Heart rate (beats per minute) | Caffeine effects heart rate recovery following aerobic exercise | up to 1 year | 
| Respiratory rate (per minute) | Caffeine effects arespiratory rate recovery following aerobic exercise | up to 1 year | 
| Oxygen saturation pulse (oximeter-SpO2) | Caffeine effects SpO2 recovery following aerobic exercise | up to 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Caffeine, Autonomic Nervous System, Recovery, Aerobic exercise