Here is the design of a clinical trial:

Official Title: Influence of the Autonomic Nervous System on Endothelial Function as an Acute Response to Exercise in Hypertensive Individuals: a Randomized Double-blind Protocol Study

Included conditions:
- Autonomic Nervous System
- Hypertension

Study Armgroups:
- {'label': 'Aerobic exercise session', 'type': 'EXPERIMENTAL', 'description': 'The aerobic exercise session will be performed on a horizontal cycle ergometer. A warm-up will be performed (5 minutes), followed by 40 minutes with moderate intensity (60% HRreserve) and controlled by a heart rate monitor, as well as the subjective effort scale (Borg 6 to 20 points). Blood pressure, heart rate and the Borg scale will be assessed at the beginning of aerobic exercise and every 5 minutes until the end.', 'interventionNames': ['Drug: α1-adrenergic block', 'Other: Placebo']}
- {'label': 'Resistance exercise session', 'type': 'EXPERIMENTAL', 'description': 'The resistance exercise session will be structured with knee extension, knee flexion, leg pressure and plantar flexion, in a station with guided weights, with 4x12 repetitions and 60% intensity of 1-RM; the cadence will be adjusted to 2:2 (concentric: eccentric) and controlled by a metronome. The rest between sets and exercises will be 90 seconds (total duration: 40 minutes). Blood pressure, heart rate and Borg scale will be recorded at the beginning and at the end of the 4th series of each exercise.', 'interventionNames': ['Drug: α1-adrenergic block', 'Other: Placebo']}
- {'label': 'Combined exercise session', 'type': 'EXPERIMENTAL', 'description': 'The combined exercise session will be structured with 20 minutes of resistance exercise + 20 minutes of aerobic exercise, as already described, except that the resistance exercises will have 2 sets of each exercise. As with other sessions, blood pressure, heart rate and the Borg scale will be assessed at the beginning and end of the second series of resistance exercise, as well as at the beginning and every 5 minutes of aerobic exercise up to 15 minutes after end of exercises.', 'interventionNames': ['Drug: α1-adrenergic block', 'Other: Placebo']}

Interventions:
- {'type': 'DRUG', 'name': 'α1-adrenergic block', 'description': 'Ninety minutes before starting the experimental exercise protocol, participants will be offered a capsule containing an α-1 adrenoreceptor blocker (Drozazosin; 0.05 mg / kg-1 body weight) and will be instructed to lie down. All capsules will be handled by a specialized pharmacy.', 'armGroupLabels': ['Aerobic exercise session', 'Combined exercise session', 'Resistance exercise session'], 'otherNames': ['Doxazosin']}
- {'type': 'OTHER', 'name': 'Placebo', 'description': 'Ninety minutes before starting the experimental exercise protocol, participants will be offered a capsule containing an placebo (microcrystalline cellulose; 0.05 mg.kg-1 body weight) and will be instructed to lie down. All capsules will be handled by a specialized pharmacy.', 'armGroupLabels': ['Aerobic exercise session', 'Combined exercise session', 'Resistance exercise session'], 'otherNames': ['Microcrystalline cellulose']}

Primary Outcomes:
- {'measure': 'Changes in the endothelial function of hypertensive individuals after a session of aerobic exercise, resistance exercise and combined exercise in α1-adrenoreceptor blocker and placebo condition.', 'description': 'The method of assessing the flow-mediated dilation (FMD) of the brachial artery by ultrasonography is an indirect method to assess endothelial function. To analyze the FMD of the brachial artery a rapid deflation cuff will be placed around the forearm 5 cm distal to the antecubital fossa and the image of the brachial artery will be obtained in the distal third of the arm. Baseline diameters will be recorded for 1 minute, before the forearm cuff is inflated at 50 mmHg above the SBP, for 5 minutes. The recording of the images will be resumed 30 seconds before the deflation of the cuff and maintained for 3 minutes after deflation. The video signal of the Doppler Ultrasound will be recorded in real time by a USB video card and saved for offline analysis. The analysis of diameter will be performed using edge detection and wall tracking software. The FMD will be calculated as the percentage change in the peak diameter after deflating the cuff from the baseline diameter.', 'timeFrame': 'Ten minutes before the exercise session and 10, 40 and 70 minutes after the exercise session.'}

Please estimate the sample size based on the assumption: 
Significance level (α) = 0.05, power = 80%, and a 30% dropout rate.
Sample size
        The sample size is calculated according to Atkinson et al. [26]. In their study, they compared endothelium-dependent vasodilation (by FMD) after a single session of moderate-intensity AE for 30âmin in healthy individuals receiving an Î±1-adrenergic blocker (prazosin 0.05âmg/kgâ1) or placebo and reported a difference in means of 3.1% with standard deviations (SDs) of 1.13% for placebo and 1.91% for prazosin. For finding a similar difference in FMD (3.1%) between these two conditions (Î±1-adrenergic receptor block versus placebo) after our protocolâs exercise session (AE, RE, and CE) considering Î± = 0.05 and 80% power, a sample of five volunteers per group (n = 15) is required.
        For a comparison of FMD measurements among exercise types (AE, RE, and CE), our sample calculation is based on pre-exercise SD (1.18%) and post-exercise SD (1.91%) for the prazosin group as described by Atkinson et al. Thus, to find a difference in FMD of 1.62% considering Î± = 0.05 and 80% power, a sample of 10 individuals per group (n = 30) is required. Assuming a 30% loss, a sample of 39 individuals would be required (n = 13 per group).