Nah, you'll be fine! But once you get a BFP definitely have to tone it down a bit. I used 30-Day Shred a lot, rode on the stationary bike until I about fell off, did a lot of walking and weights and crunches. Once I got the BFP though I reduced it to just walking until I saw my doctor (I've had 2 m/c so I didn't want to risk anything). He told me I could still ride the stationary bike, swim, walk, do light handweights, etc.
Thanks, JoyRenee! I try not to do exercises that involve me bouncing around too much, like running, but I'm glad I shouldn't have to reduce my work outs to a minimum.
Exercise does not affect implantation.
I got pregnant doing very intense workouts almost every day. If anything exercise can help with conception as your body is more healthy and prepared to grow a baby.