Aloha peakinside,
It's about letting the energy and intention you've been working with settle into the system. Would I go out and walk afterwards, sure (avoiding cold weather). Would I go for a 5-mile run? Nope. I'd wait and give it 20-30 minutes.
Is exercise for you some yoga poses? Then I'd be okay moving into my active exercises afterwaards.
Depends on what you're definition of exercise is.
Heck, there are time when I would drive after a deep meditation following my active exercises!

Much Love,
Shawn