Diaphragmatic Breathing Exercises With KOTS Currents in Patients With Long COVID

NCT07621588 | Not Yet Recruiting

• 1 other identifier: UPSA-KOTS-LC-2025
• Study Type: interventional
• Target: 10
• Locations: 1 country
• Sites: 1

Brief Summary

This study will evaluate the effects of diaphragmatic breathing exercises combined with diaphragmatic electrostimulation using KOTS currents in patients with Long COVID. Participants will be randomly assigned to one of two groups. The control group will perform diaphragmatic breathing exercises, while the intervention group will perform diaphragmatic breathing exercises combined with diaphragmatic electrostimulation using KOTS currents. The intervention will last three weeks, with two sessions per week. The study will assess respiratory function, quality of life, physical function, dyspnea, fatigue, and basal oxygen saturation.

Conditions

Long COVID Syndrome; Post-Acute COVID-19 Syndrome

Keywords

Diaphragmatic Breathing; KOTS Currents; Russian Currents; Diaphragmatic Electrostimulation; Quality of Life; Respiratory Rehabilitation; Spirometry

Outcome Measures

Primary Outcomes (1)

• Forced Vital Capacity

  Forced vital capacity will be assessed using spirometry. The outcome will evaluate the change in forced vital capacity from baseline to after the three-week intervention.

  Baseline and 3 weeks

Secondary Outcomes (8)

• Forced Expiratory Volume in One Second

  Baseline and 3 weeks

• Peak Expiratory Flow

  Baseline and 3 weeks

• FEV1/FVC Ratio

  Baseline and 3 weeks

• Basal Oxygen Saturation

  Baseline and 3 weeks

• Physical Function

  Baseline and 3 weeks

Study Arms (2)

Diaphragmatic Breathing Exercises Plus KOTS Currents

EXPERIMENTAL

Participants assigned to this arm will perform diaphragmatic breathing exercises combined with diaphragmatic electrostimulation using KOTS currents. The intervention will be delivered twice per week for three weeks. KOTS currents will be applied as medium-frequency alternating current stimulation, with stimulation intensity adjusted according to participant tolerance.

Device: Diaphragmatic Electrostimulation Using KOTS Currents; Behavioral: Diaphragmatic Breathing Exercises

Diaphragmatic Breathing Exercises

ACTIVE COMPARATOR

Participants assigned to this arm will perform diaphragmatic breathing exercises twice per week for three weeks. Exercises will be performed in a supine position, with slow nasal inspiration and abdominal expansion followed by slow exhalation through pursed lips.

Behavioral: Diaphragmatic Breathing Exercises

Interventions

Diaphragmatic Electrostimulation Using KOTS Currents DEVICE

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.

Also known as: KOTS Currents, Russian Currents

Diaphragmatic Breathing Exercises Plus KOTS Currents

Diaphragmatic Breathing Exercises BEHAVIORAL

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.

Also known as: Diaphragmatic Breathing

Diaphragmatic Breathing Exercises; Diaphragmatic Breathing Exercises Plus KOTS Currents

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• 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.

You may not qualify if:

• 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.

Sponsors & Collaborators

• Universidad Pontificia de Salamanca: lead

Study Sites (1)

Clínica Universitaria Salus Infirmorum, Universidad Pontificia de Salamanca

Madrid, Madrid, 28015, Spain

Location

MeSH Terms

Conditions

Post-Acute COVID-19 Syndrome

Condition Hierarchy (Ancestors)

COVID-19; Pneumonia, Viral; Pneumonia; Respiratory Tract Infections; Infections; Virus Diseases; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; RNA Virus Infections; Lung Diseases; Respiratory Tract Diseases; Post-Infectious Disorders; Chronic Disease; Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Sara Perpiña-Martínez

  Pontifical University of Salamanca

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Sara Perpiña-Martinez

CONTACT

(+34) 910053661; sperpinama@upsa.es

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: The outcomes assessor was masked to group allocation. Participants were assigned to either diaphragmatic breathing exercises alone or diaphragmatic breathing exercises combined with diaphragmatic electrostimulation using KOTS currents.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal investigator and Professor of Physiotherapy

Model Details: Participants will be randomly assigned to one of two parallel groups: diaphragmatic breathing exercises alone or diaphragmatic breathing exercises combined with diaphragmatic electrostimulation using KOTS currents.

Study Record Dates

• First Submitted: May 27, 2026
• First Posted: June 2, 2026
• Study Start: June 1, 2026
• Primary Completion: July 1, 2026
• Study Completion: July 1, 2026
• Last Updated: June 4, 2026

Record last verified: 2026-06

Data Sharing

• IPD Sharing: Will not share

Locations

ES (1)