Cycle Ergometer with Vibration Isolation and Stabilization System (CEVIS) - 06.18.15
Cycle Ergometer with Vibration Isolation and Stabilization System (CEVIS) provides aerobic and cardiovascular conditioning through recumbent cycling activities. Science Results for Everyone Cycling in space may conjure up images of Miss Gulch from the Wizard of Oz, but it provides important conditioning for astronauts. This is especially important for physically demanding space-walk activities outside the space station. Future plans call for up to 24 hours of Extra Vehicular Activity (EVA) per week during lunar and Martian missions, but early evidence suggests this long EVA may be too strenuous. According to the Cycle Ergometer with Vibration Isolation and Stabilization System (CEVIS) investigation, cycling in space could help improve physical stamina for extended EVAs. The study found that exercise heart rate initially goes up during onboard exercise, but approaches preflight levels later on in missions, owing perhaps to the rigoruous exercise regimens, including pedaling. Facility Details
Danish Aerospace Company, Copenhagen, Denmark
Sponsoring Space Agency
National Aeronautics and Space Administration (NASA)
Human Exploration and Operations Mission Directorate (HEOMD)
ISS Expedition Duration
March 2001 - March 2014
Previous ISS Missions
CEVIS was launched during Expedition 2.
- Cycle Ergometer with Vibration Isolation and Stabilization System (CEVIS), essentially a recumbent bicycle, provides aerobic exercise and is intended as a countermeasure for the harmful physiological effects of exposure to microgravity that are anticipated during stays on the ISS.
- CEVIS is utilized as part of the crewmembers weekly exercise schedule.
- CEVIS is designed for use as a component of the Crew Health Care System (CHeCS) and Human Research Facility (HRF) on the ISS.
- CEVIS also has the capability to support ISS science activities, pre-breathe extravehicular activities (EVA), periodic fitness evaluations (PFE), and pre-landing fitness evaluations.
CEVIS is a modified version of the Shuttle Inertial Vibration Isolation and Stabilization (IVIS) Cycle Ergometer with the principal difference being the addition of an electronic control system. CEVIS is computer controlled and maintains a very accurate workload independent of the pedaling speed of the crewmember. The CEVIS control panel displays target and actual workload, cycling speed, and heart rate as well as deviation from target cycling speed and heart rate, exercise elapsed time, and protocol. Desired workload for exercise is controlled in the range of 25 to 350 W, in 1 W increments and target and actual pedal speeds from 30 to 120 rpms are displayed. Target and actual parameters (speed, workload, and heart rate), which are defined by predefined protocols or user-defined parameters, are recorded to a PCMCIA (Portable Computer Memory Card International Adapter) Card.
The Ergometer portion of CEVIS is constructed of aluminum and weighs approximately 59 lbs. The exposed moving parts consist of crank arms, pedals, handles, and a clevis fixed to a drive rod. The pedals, when rotated, drive a flywheel through a planetary gear set. The inertial vibration isolation system is used to counteract the motions generated by a crewmember exercising on CEVIS. The isolators provide station-keeping of the rider/cycle system during operations. CEVIS is certified for 15 years on-orbit. ^ back to top
- Crewmember places Heart Rate Monitor chest strap, transmitter and watch on.
- The PCMCIA card with exercise prescription is inserted into the CEVIS display and the crewmember follows prescribed or user-defined exercise protocol.
- CEVIS is located and operated in the Destiny module onboard the ISS.
The majority of the data collected to date in the U.S. space program suggests that in-flight maximum oxygen consumption (VO2 max), even with minimal countermeasure participation, is maintained during short duration missions (<14 days). However, there are no clear results yet available from long duration missions. Data from US astronauts performing sub-maximal exercise tests during Skylab and ISS conflict; however, preliminary data from our laboratory suggest that differences in the cycle ergometers used for in-flight testing may largely explain this discrepancy. VO2 max is consistently decreased after short-duration flight, but no similar data are yet available following long-duration missions. Sub-maximal exercise heart rate is elevated afterlong duration spaceflight but recovers top re-fligh tlevels by30 days after landing. Elevated sub-maximal heart rate during and after flight is assumed tore flect decreased VO2 max, and this assumption will soon be tested in an upcoming flight experiment. Microgravity EVA has been successfully completed on both short and long duration missions, although the efficiency of EVA relative to an astronaut’s physical fitness has not been systematically evaluated. NASA’s experience with EVA in partial gravity has been limited to14EVAs during the Apollo era,and none of the Apollo crews completed more than three lunar EVAs per mission. Therefore, it is unknown whether current plans to include up to 24h of EVA per crewmember per week during lunar and Martian exploration missions are feasible. Preliminary evidence suggests that the metabolic cost of performing contingency tasks, such as a 10 km return to base, is high and may exceed the aerobic capacity of some astronauts. Current and future investigations will seek to determine the optimal suit design for partial gravity EVA, further define the physical requirements of the tasks required for exploration missions, and refine the countermeasures for longer duration space flightResults Publications
Moore Jr. AD, Lee SM, Stenger MB, Platts SH. Cardiovascular Exercise in the U.S. Space Program: Past, Present and Future. Acta Astronautica. 2010 Apr-May; 66(7-8): 974-988. DOI: 10.1016/j.actaastro.2009.10.009.
Ground Based Results Publications