2.2. Instruments and Data Collection
After signing the Informed Consent Forms, an anamnesis form was used to measure anthropometric variables such as weight and height, and clinical history.We controlled the ambient temperature (between 21 °C and 23 °C) and humidity (between 40 and 60%), and prepared the equipment before participants arrived at the testing location. Patients were weighed on an electronic scale with a capacity of up to 150 kg and subdivisions of up to 10 g, without shoes and wearing as little clothing as possible. To measure height, patients placed their heels, calves, buttocks, and shoulders against the wall, positioning their heads according to the Frankfurt plane. We used a wall-mounted stadiometer with subdivisions in centimeters and millimeters [After this first evaluation, the IPAQ was administered. The IPAQ is a scale validated in Brazil and proposed by the World Health Organization in 1998 that is used as a global instrument to determine the population level of physical activity [Initially, measurements of systolic (SBP) and diastolic (DBP) blood pressure and heart rate were collected. SBP and DBP data were obtained as a single measurement, indirectly verified by means of a Welch Allyn aneroid sphygmomanometer positioned in the subject’s left arm and a Littmann-3M Classic II stethoscope over the median region of the antecubital fossa. To measure the respiratory rate, a stopwatch was used to count how many thoracic incursions the patient made in one min. HR was recorded using a Polar brand S800CX heart rate monitor. The capture strap was placed in the chest of participants, and the heart rate receiver watch (RS800CX, PolarAfter placement of the strap and monitor, participants were kept in the supine position and remained at rest for 10 min for baseline HRV capture. Data collection was performed from 1 p.m. to 4 p.m. to avoid changes arising from the circadian cycle in the HRV. After data collection, the heart rate monitor was connected to a wireless receiver computer and the data were transferred to an HRV analysis program (Polar Trainer 5) [We conducted our analysis using the Kubios HRV analysis software (version 2.0.; Kuopio, Finland—University of Eastern Finland—After digital filtering, the signal was divided into five moments “Rest” originated from a period of 10 min of rest and “exercise” counted as 20 min of the exercise period, that is, the first and last five mins of the 30 min of exercise were disregarded. This cut was made to remove the warm-up and deceleration period of the heart rate, characterizing only the exercise period in the elderly aerobic training zone. “Recovery” consisted of the patient’s recovery period post-exercise. The heart rate variability in this recovery period was divided into three new periods: first (Recovery 1 or R1) within the initial five mins of recovery, second (Recovery 2 or R2) between the tenth to the fifteenth min, and third (R3) from the twenty-fifth to the thirtieth min [Patients after a 10-min rest were directed to aerobic training (5-min jogging and 25-min running) on a treadmill for 30 min, maintaining the stipulated training heart rate (70% of the maximum HR). After 30 min, participants were directed to rest in the supine position for another 30 min for the data collection on their recovery time.