Similarly for their US counterparts. The astronauts were stressed in training far beyond what they'd ever encounter in real space flight. It is a miracle that there weren't more injuries or fatalities in the space program.
But in the Mercury/Vostok era, astronauts were more test subjects than they were pilots. There was very little to gain except for publicity from sending humans to space. The scientific goals could have been accomplished with animal test subjects. The role of astronauts became more involved later in the Gemini/Apollo/Soyuz era with rendez-vous, docking and EVA operations.
But in the Mercury/Vostok era, astronauts were more test subjects than they were pilots. There was very little to gain except for publicity from sending humans to space. The scientific goals could have been accomplished with animal test subjects. The role of astronauts became more involved later in the Gemini/Apollo/Soyuz era with rendez-vous, docking and EVA operations.