Peter Attia· MD
when they send the first human being in space Yuri Garin they were able to send back the ECG and some respiratory data and see fundamentally what happened to people when you shot them into space which they really didn't have a way of gauging without this and so they saw as soon as he went into space his HRV went way up probably because you have changes in blood pressure you'd have less gravity so you don't have to have as much muscle activity