Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
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.
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| Label | Type | Description | Intervention Names |
|---|---|---|---|
| Control | Sham Comparator | Sham altitude changes - The CVAC device consists of a small pod-like chamber attached to a computer system that controls a strong pump that can draw air rapidly out of the chamber to increase the simulated altitude. The sham-treated group (SH) was exposed to regular, slowly-fluctuating pressures that reached a maximum altitude of 607 m for all 30 sessions. Sham sessions mimicked the noises and initial pressure-change sensations created in the active sessions, thus giving naıve subjects the impression that they were experiencing altitude treatment. All subjects were blind to their elevation throughout the intervention. |
|
| Hypoxic intervention | Experimental | Cyclic Hypobaric Hypoxia (CHH) subjects were given 40 min sessions inside the CVAC device per day (two 20 min sessions sequentially per day), 3 days a week for 10 weeks, for a total of 30 sessions or 20 hours. After familiarization sessions, pre-programmed sessions were administered, progressing from Tier 1 to 5. Subjects rotated through three pre-programmed sessions per Tier and each session varied the pattern and rate of hypoxic fluctuations, so that subjects would experience a constantly changing stimulus at each elevation. Five weeks were allotted to progress from Tier 1 (3048 m) to Tier 4 (5486 m). At Tier 5 (6096 m), there was an additional 5 weeks of exposure. |
|
| Name | Type | Description | Arm Group Labels | Other Names |
|---|---|---|---|---|
| CVAC Device (Cyclic Variations in Altitude Conditioning) | Device | A hypobaric hypoxia chamber |
|
| Measure | Description | 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). |
Not provided
Not provided
Inclusion Criteria:
Exclusion Criteria:
Not provided
Not provided
Not provided
Not provided
Not provided
| Name | Affiliation | Role |
|---|---|---|
| Anne Friedlander, PhD | Veterans Affairs Palo Alto Health Care System | Principal Investigator |
Not provided
Medical Screening Group Matching by 3rd party
Recruited from Palo Alto and surrounding areas by flyer and advertisement
Not provided
| ID | Title | Description |
|---|---|---|
| FG000 | Sham Group | Slowly fluctuating pressures simulating altitude up to 607 meters |
| FG001 | Cyclic Hypoxic Group | Rapidly fluctuating pressures simulating altitude up to 6096 meters |
| Title | Milestones | Reasons Not Completed | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Overall Study |
|
Not provided
Not provided
| ID | Title | Description |
|---|---|---|
| BG000 | Sham Group | Slowly fluctuating pressures simulating altitude up to 607 meters |
| BG001 | Cyclic Hypoxic Group | Rapidly fluctuating pressures simulating altitude up to 6096 meters |
| Units | Counts |
|---|---|
| Participants |
|
| Title | Description | Population Description | Parameter Type | Dispersion Type | Unit of Measure | Calculate Percentage | Denominator Units Selected | Denominators | Classes |
|---|---|---|---|---|---|---|---|---|---|
| Age, Categorical | Count of Participants |
| Type | Title | Description | Population Description | Reporting Status | Anticipated Posting Date | Parameter Type | Dispersion Type | Unit of Measure | Calculate Percentage | Time Frame | Units Analyzed | Denominator Units Selected | Arm/Group Information | Denominators | Classes | Analyses | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Primary | Plasma Glucose Concentration | Those that completed the study | Posted | Mean | Standard Deviation | mg/dl | 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). |
|
The events occured over the 1 year period of the study
The events did not require medical attention, but prevented the subjects from advancing to the higher levels of altitude exposure
Not provided
| ID | Title | Description | Deaths (Affected) | Deaths (At Risk) | Serious Events (Affected) | Serious Events (At Risk) | Other Events (Affected) | Other Events (At Risk) |
|---|---|---|---|---|---|---|---|---|
| EG000 | Sham Group | Slowly fluctuating simulated altitude up to 607 meters. |
Not provided
| Term | Organ System | Source Vocabulary | Assessment Type | Notes | Statistical Information |
|---|---|---|---|---|---|
| Ear pain | Ear and labyrinth disorders | Non-systematic Assessment | 3 subjects felt ear pain with the changing pressure caused by the cyclic hypoxia and did not wish to continue to the highest elevation tiers. |
Small Sample size
| Title | Organization | Phone | Extension | |
|---|---|---|---|---|
| Anne L Friedlander | Stanford University | 650-725-7531 | afriedlanderCW@gmail.com |
Not provided
| ID | Term |
|---|---|
| D000860 | Hypoxia |
| ID | Term |
|---|---|
| D012818 | Signs and Symptoms, Respiratory |
| D012816 | Signs and Symptoms |
| D013568 | Pathological Conditions, Signs and Symptoms |
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| BG002 | Total | Total of all reporting groups |
| Participants |
|
| Age, Continuous | Mean | Standard Deviation | years |
|
| Sex: Female, Male | Count of Participants | Participants |
|
| Region of Enrollment | Number | participants |
|
| Units |
|---|
| Counts |
|---|
| Participants |
|
|
| 0 |
| 13 |
| 0 |
| 13 |
| EG001 | Cyclic Hypoxic Group | Rapidly fluctuating simulated altitude up to 6097 meters | 0 | 15 | 3 | 15 |
|
Not provided
Not provided