Hypoxia
Conditions
Brief summary
Cyclic Variation in Altitude Conditioning (CVAC) is a new technique that uses a pod-like device to expose users to controlled fluctuations in air pressure. It is designed to promote quicker altitude acclimatization, thus promoting improvements in exercise capacity at altitude and, possibly, at sea level. However, over the past few years, anecdotal stories from users of the device suggest that the CVAC treatments might be causing changes beyond the expected endurance exercise performance benefits. Therefore, the purpose of the study is to obtain data on some of the previous anecdotal claims regarding the device (e.g. increases in strength, improved glucose tolerance, reduction of neuropathic pain and decreased joint swelling) as well as to obtain broad questionnaire data in order to identify more specific variables to investigate in future studies.
Interventions
DEVICECVAC Device (Cyclic Variations in Altitude Conditioning)
A hypobaric hypoxia chamber
Sponsors
Palo Alto Veterans Institute for Research
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
HEALTH_SERVICES_RESEARCH
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
40 Years to 70 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy middle aged men at risk for metabolic syndrome
Exclusion criteria
* Uncontrolled hypertension, * sensitive ears, * anything that would preclude person from sustaining rapid pressure changes
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Plasma Glucose Concentration | Glucose measurements were made at baseline, 3, 6, & 10 weeks. Blood was collected consistently after a 10-12 h fast the morning after a CVAC session (except for baseline). |
Participant flow
Recruitment details
Recruited from Palo Alto and surrounding areas by flyer and advertisement
Pre-assignment details
Medical Screening Group Matching by 3rd party
Participants by arm
| Arm | Count |
|---|---|
| Sham Group Slowly fluctuating pressures simulating altitude up to 607 meters | 13 |
| Cyclic Hypoxic Group Rapidly fluctuating pressures simulating altitude up to 6096 meters | 15 |
| Total | 28 |
Baseline characteristics
| Characteristic | Cyclic Hypoxic Group | Sham Group | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical Between 18 and 65 years | 15 Participants | 13 Participants | 28 Participants |
| Age, Continuous | 48 years STANDARD_DEVIATION 6 | 50 years STANDARD_DEVIATION 4 | 49 years STANDARD_DEVIATION 6 |
| Region of Enrollment United States | 15 participants | 13 participants | 28 participants |
| Sex: Female, Male Female | 0 Participants | 0 Participants | 0 Participants |
| Sex: Female, Male Male | 15 Participants | 13 Participants | 28 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 13 | 3 / 15 |
| serious Total, serious adverse events | 0 / 13 | 0 / 15 |
Outcome results
Primary
Plasma Glucose Concentration
Time frame: Glucose measurements were made at baseline, 3, 6, & 10 weeks. Blood was collected consistently after a 10-12 h fast the morning after a CVAC session (except for baseline).
Population: Those that completed the study
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Sham Group | Plasma Glucose Concentration | Baseline | 93.8 mg/dl | Standard Deviation 7.6 |
| Sham Group | Plasma Glucose Concentration | 3 weeks | 94.1 mg/dl | Standard Deviation 6.2 |
| Sham Group | Plasma Glucose Concentration | 6 weeks | 95.3 mg/dl | Standard Deviation 7.5 |
| Sham Group | Plasma Glucose Concentration | 10 weeks | 96.8 mg/dl | Standard Deviation 8.9 |
| Cyclic Hypoxic Group | Plasma Glucose Concentration | 10 weeks | 90.8 mg/dl | Standard Deviation 6.9 |
| Cyclic Hypoxic Group | Plasma Glucose Concentration | Baseline | 95.7 mg/dl | Standard Deviation 9 |
| Cyclic Hypoxic Group | Plasma Glucose Concentration | 6 weeks | 92.5 mg/dl | Standard Deviation 4.3 |
| Cyclic Hypoxic Group | Plasma Glucose Concentration | 3 weeks | 93.3 mg/dl | Standard Deviation 8.5 |