How Can I Exercise In Secret?

Ok, it sounds really stupid but, I can't really ever exercise when people are in the house with me at the same time. I used to exercise all of the time, and I got really toned and stuff, but because I was on my exercise bike everyday my mum got really suspicious because she kept asking why I was exercising all of the time. Usually, I dance, hula hoop, and go on my exercise bike and sometimes run around the house. I love exercising, but recently I haven't been able to do as much and I've put on some weight and I'm not as toned as I was, especially aroudn my thighs and stomach area. I mean, I'm not overweight at all, but I really want to exercise like I used to, without my mum being obsessed. Is there anything I can do whilst they're still at home, that doesn't make a lot of noise but is still effective? I've found that my exercise bike is the best, but because it's in my room upstairs, you can hear all over the house; I go pretty fast lol.

well just tell your mom that you want to excercise.
its not a bad thing
its good for you
if only more people wanted to excercise lie you
if you still want to in secret
try small things
like puchups, crunches, and so on that you can so in a small area and dosnt make noise

go to gym maybe

try going outside