Participants walk at 5,5 km/h on treadmill for 6 minutes. Participants in the experimental group will perform intermittent apneas at low lung volume with a density of 15 seconds, followed by a normal breath of 10 seconds (15 cycles of 15s apnea - 10s normal breathing, until completing the 6 minutes).

Participants walk at 5,5 km/h on treadmill for 6 minutes. Participants in the control group will remain breathing normally for these 6 minutes.

Walking apneas at low lung volume

PPT is tested on the dorsal base of the distal phalanx of the thumb on the dominant side and on the muscle belly of the tibialis anterior on the dominant side. The region to be pressed is marked with a pen. The patient is instructed to report with the first appearance of the sensation of "discomfort". An ascending ramp of 0.5 kg/cm/s is applied, at the rhythm of a metronome. The measurement is started on the thumb, and alternated with tibia and C7 until 3 measurements of each region are obtained, enough time to give 30 seconds of rest between measurements in the same region. This protocol has demonstrated high inter-observer reliability measuring healthy subjects (ICC = 0.91).

14-item questionnaire about their thoughts and feelings in the last month. The scale has a range of scores from 0 to 56. The lower the score, the more favorable for the patient's health.