This study will evaluate the effects of diaphragmatic breathing exercises combined withdiaphragmatic electrostimulation using KOTS currents in patients with Long COVID.Participants will be randomly assigned to one of two groups. The control group willperform diaphragmatic breathing exercises, while the intervention group will performdiaphragmatic breathing exercises combined with diaphragmatic electrostimulation usingKOTS currents. The intervention will last three weeks, with two sessions per week. Thestudy will assess respiratory function, quality of life, physical function, dyspnea,fatigue, and basal oxygen saturation.
Long COVID is a multifactorial condition that may be associated with persistent
respiratory symptoms, reduced physical capacity, fatigue, dyspnea, and impaired quality
of life. Respiratory rehabilitation strategies may contribute to improving breathing
patterns and functional recovery in this population. Diaphragmatic breathing exercises
are commonly used to promote respiratory control and diaphragmatic activation. In
addition, KOTS currents, also known as Russian currents, are medium-frequency alternating
currents used in physiotherapy to elicit muscle contraction and may be applied as a
complementary strategy to stimulate the diaphragm.
This pilot randomized controlled trial will compare diaphragmatic breathing exercises
alone with diaphragmatic breathing exercises combined with diaphragmatic
electrostimulation using KOTS currents in patients diagnosed with Long COVID.
Participants will be randomly allocated to either the control group or the intervention
group. Both groups will receive a three-week intervention consisting of two sessions per
week. The control group will perform diaphragmatic breathing exercises, whereas the
intervention group will perform the same breathing exercises combined with diaphragmatic
electrostimulation.
Assessments will be conducted before and after the intervention period. The study is
intended to explore whether adding diaphragmatic electrostimulation to a respiratory
exercise program may provide additional benefits compared with diaphragmatic breathing
exercises alone in this population.
Device: Diaphragmatic Electrostimulation Using KOTS Currents
Diaphragmatic electrostimulation will be applied using KOTS currents, a medium-frequency
alternating current stimulation. Electrodes will be placed over the seventh and eighth
rib region along the mammillary line. Stimulation will be delivered in trains of 4
seconds of stimulation followed by 8 seconds of rest, with a carrier frequency of 2,500
Hz. The standard treatment duration will be 15 minutes: 10 minutes at 30 Hz followed by 5
minutes at 70 Hz. Stimulation intensity will be adjusted according to participant
tolerance. The intervention will be delivered twice per week for three weeks, together
with diaphragmatic breathing exercises.
Other Name: KOTS Currents,Russian Currents
Behavioral: Diaphragmatic Breathing Exercises
Participants will perform diaphragmatic breathing exercises in a supine position with the
knees flexed. One hand will be placed on the chest and the other hand below the sternum.
Participants will be instructed to inhale through the nose while expanding the abdomen
with minimal thoracic movement, and to exhale slowly through pursed lips. The breathing
pattern will include a 4-second inspiration and a 6-second expiration. Exercises will be
performed twice per week for three weeks.
Other Name: Diaphragmatic Breathing
Inclusion Criteria:
- Men and women aged 18 to 65 years.
- Medical diagnosis of Long COVID.
- At least 2 months since SARS-CoV-2 infection.
- Ability and willingness to provide informed consent.
- Ability to participate in the assigned intervention and assessment procedures.
Exclusion Criteria:
- Presence of a pacemaker.
- History of epilepsy.
- Pregnancy.
- History of acute cardiac arrest.
- Severe respiratory distress.
- Use of a wheelchair.
- Blurred vision.
- Cyanosis.
- Refusal to perform part or all of the treatment.
- Incomplete or incorrectly completed questionnaires.
Clínica Universitaria Salus Infirmorum, Universidad Pontificia de Salamanca
Madrid, Madrid, Spain
Investigator: Sara Perpiña Martínez
Contact: (+34) 910053661
sperpinama@upsa.es
Sara Perpiña-Martinez
(+34) 910053661
sperpinama@upsa.es
Sara Perpiña-Martínez, Principal Investigator
Pontifical University of Salamanca