I know a guy that takes part in chamber trials. He reckons that when they monitor you, every time you move it produces a flurry of bubbles.
If you have ever wondered what decompression sounds like, try this link
Doppler recording
The idea of gentle exercise during decompression is to keep the blood flowing, like the exercises in the inflight mags on long haul flights. I usually have a gentle fin about about and wiggle my fingers.
A bit OT but I know a guy who got hit quite badly driving up the hill out of Weymouth.
AIUI the risky time is the first couple of hours but its safest to avoid heavy exercise for at least 8 hours.
Your ontop tonight luv!
Regards
Matt