While astronauts might not notice the change, there are some sensations they feel "instantaneously", Peake explained.
But it's not just the floaty feeling astronauts notice - the weightlessness could even make you feel like you've got the flu.
You also feel like you're hunching more often, due to the lack of gravity, which is an "unusual" feeling, he added.
"You feel the effects of weightlessness instantaneously," Peake told Express.co.uk.
"The moment the main energy cuts out, and you enter weightlessness, you feel the shift in your body fluid.
So you feel your body shape into this semi-foetal position, which is the relaxed, natural position in weightlessness
However, astronauts don't tend to notice these more long-term changes, Peake said