"Hypoxic vs. Aerobic Training in Chronic Kidney Disease
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: hypoventilation group.
- Who it may be relevant to
- Registry conditions: Chronic Kidney Disease (CKD), Stages 3-4 Exercise Tolerance / Functional Capacity Vascular Health / Arterial Stiffness Fatigue in CKD. Basic parameters: 40 years — 65 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Center list to be confirmed — check the primary protocol.
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
Simulated Hypoxia Training to Enhance Exercise Tolerance in Stage 3 Chronic Kidney Disease: A Randomized Controlled Trial
Overview
Chronic kidney disease (CKD) leads to poor exercise tolerance, vascular dysfunction, and reduced quality of life. This randomized controlled trial will compare intermittent hypoxic training (IHT) with traditional aerobic training in patients with CKD stages 3-4. A total of 60 participants aged 40-65 years will be recruited and randomized into three groups. Interventions will last 12 weeks, with three 30-minute supervised sessions per week. Outcome measures include exercise tolerance (6-Minute Walk Test), cardiovascular parameters (blood pressure, heart rate recovery), kidney function (serum creatinine, eGFR), fatigue (Fatigue Severity Scale), and quality of life (KDQOL-36)
Detailed description
Chronic kidney disease (CKD) stage 3 is characterized by reduced exercise capacity, muscle weakness, and increased cardiovascular risk, which negatively impact quality of life. Exercise interventions have shown benefits in improving functional outcomes, but traditional aerobic training may be limited due to comorbidities and reduced physiological reserve. Intermittent hypoxic training (IHT) improves oxygen utilization, cardiovascular adaptation, and mitochondrial function. Specialized hypoxicator devices are costly and not widely available, so practical alternatives such as hypoventilation training and breathing restriction masks may provide comparable benefits.
Study Objective:
To evaluate the effects of hypoventilation training and breathing restriction mask training on exercise tolerance, cardiovascular function, kidney function, fatigue, and quality of life in CKD stage 3 patients.
Study Design:
Randomized controlled trial including 60 patients with CKD stage 3, aged 40-65 years, recruited from outpatient clinics at Aboker Hospital and Pharos University. Participants will be screened for eligibility through medical history, vital signs, and laboratory tests (serum creatinine, eGFR, hemoglobin, electrolytes).
Interventions:
Group A - Hypoventilation Training:
Moderate-intensity aerobic exercise on a cycle ergometer (40-60% HR reserve)
Intermittent breath-holding: 5-10 seconds every 1-2 minutes
Continuous monitoring of SpO₂, heart rate, and blood pressure
Group B - Breathing Restriction Mask Training:
Same aerobic protocol as Group A
Participants wear an adjustable resistance mask to simulate hypoxia
Mask set to induce mild hypoxemia (SpO₂ ≥85%)
Continuous monitoring of SpO₂, heart rate, and blood pressure
Group C - Control Group:
Same aerobic exercise protocol under normal breathing conditions
Moderate intensity (40-60% HR reserve)
Periodic monitoring of vital signs for safety
Intervention Duration:
12 weeks, 3 supervised sessions per week, 30 minutes per session
Outcome Measures:
Primary Outcome:
Exercise tolerance assessed via 6-Minute Walk Test (6MWT) at baseline and post-intervention
Secondary Outcomes:
Fatigue: Fatigue Severity Scale (FSS), self-reported, 9 items, 7-point Likert scale
Quality of Life: KDQOL-36, disease-specific questionnaire covering physical/mental health, symptoms, effects, and burden of CKD
Cardiovascular Assessment: Blood pressure (SBP, DBP) and Heart Rate Recovery (HRR = HR\_peak - HR\_1min)
Kidney Function: Serum creatinine and eGFR (CKD-EPI/MDRD
Interventions
- Behavioral hypoventilation group
Traditional Aerobic Training Participants will perform supervised aerobic exercise (e.g., cycling or treadmill walking) under controlled intermittent hypoxic conditions. Hypoxia protocol: alternating cycles of low-oxygen exposure (FiO₂ 12-16%) for 3-5 minutes followed by normoxic recovery for 2-3 minutes, repeated 6-8 times per session. Frequency: 3 sessions per week for 12 weeks. Exercise intensity: Moderate (50-70% of heart rate reserve), adjusted individually based on baseline exercise tes
Primary outcome measures
- Six-Minute Walk Test (6MWT) distance [Time frame: 12 weeks]
Secondary outcome measures (2)
- Fatigue Severity Scale (FSS) [Time frame: 12 wwks]
- Kidney Disease Quality of Life Questionnaire (KDQOL-36) [Time frame: 12 weeks]
Eligibility criteria
Inclusion Criteria:Adults (40-65 years) diagnosed with CKD stages 3a,b
- Medically stable and cleared for exercise
Exclusion criteria
- Uncontrolled hypertension
- Severe cardiac arrhythmias
- Recent hospitalization (<3 months)
cardiovascular disese unstable
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: Yes
Study design
- Allocation
- Randomized
- Model
- Parallel assignment
- Masking
- Single blind
- Primary purpose
- Treatment
Study locations
Center list to be confirmed — check the primary protocol.
Identifiers
NCT: NCT07180875 · OlaElgohary-IHT-CKD-01