The cardiovascular changes induced by microgravity are in general described as the result of the loss of hydrostatic pressure. Other factors are also important: restricted environment with 1) elimination of mobility, action and 2) isolation always found in space environment or during simulation studies. Several studies indicate an analogy between microgravity and confinement. The results of simulation studies could be misinterpreted without a control confinement study present in the protocol.
Labortatoire de Physiologie de l'Environnement, (GIP-Exercise, DRET and CNES) Faculté de Médecine Grange Blanche, F-69373 Lyon Cedex 08, FRANCE
Submitted for publication December 1995.
Accepted for publication May 1996.
Address for correspondence: C. Gharib, Labortatoire de Physiologie de l'Environnement, (GIP-Exercise-DRET), Faculté de Médecine Grange Blanche, 8, avenue Rockefeller, F-69373 Lyon Cedex 08, France.