I am coming very late to this.
I started Tae Kwon Do two three weeks ago (I go three times a week for an hour) and I ride my bike nearly every day. I am using MyFitnessPal to track my calories and I am staying on track.
I weighed about 270 when I started - and am now at 268 (this is right on track for me considering the muscle gain from the strength training at TKD and biking).
I test for my first earned belt this Saturday (we use a 14 belt system - so I am not even close to the traditional first belt - yellow - in many TKD systems). I don't mind this - and have been having a great time.
I ride between 1/2 hour to 1 1/2 hours per day. I have been using the 'Zombies, RUN!' app for my iphone - and LOVE it. So much fun.