Wow, you are doing an AWESOME job. Congrats...do you feel wonderful?
I've been a bicycle commuter from Bainbridge Island, WA to Seattle via ferry for about 6 1/2 years (started at a weight of about 244, lost (gasp) a total of 7 pounds from cycling over the years. Because I live and work on hills, and get down to sea level for ferry, I have gotten lots of leg strength from biking up hills as an obese person. If you are new to cycling, this is a great time of year to get started. Go slow, stay comfortable-but-always-pushing a little. Increase time on the bike by no more than 5 to 10% at a time, stay at that level for a while, then push up again.
My surgeon group includes fitness counseling as part of their 2-year follow-up program. I really credit the strength training I’ve done as making me strong as a cyclist. I started out doing 10 push-ups from a standing position against a kitchen counter, crunches with legs in the air—10 reps of left, center, right crunches, front and side planks, plus a couple of other things. I kept upping intensity as I gained strength (doing these every other day), and now I’m up to 2 sets of 15 reps regular push-ups, 70 reps of the l,c,r crunches, minute-plus planks, plus a few other things. I believe strongly that core strength is a lot of what is making me so strong on the bike.
A huge part of me taking up distance cycling is that I was invited to cycle with a group of women that ride every Sunday. From there, I’ve branched out to 3 other riding groups of differing speeds/intensity levels. I get so much out of biking with a group, and it keeps me enthused and excited for my Saturday and Sunday rides. Plus, a lot of those bike guys are cute (jk, hubby comes with me!!!).
Hope this is helpful, and that you find cycling as rewarding and physically conditioning as I have.