At least check with the doctor as to the timing of your progression, likely from a full and/or nonweight-bearing cast to a partial and/or walking cast, etc. With that timeframe in hand, you will want to do every friggin' exercise they give you and then some, especially while in casts. Once the cast comes off, you find out how much you were relying on it for support, so keep all your muscles flexing and ready for supporting the leg. You'll be surprised if you find yourself back on crutches or using a cane after having been in a walking cast, but you work through this stage quickly if you were exercising.
I broke the tibia and fibula and ankle all at the same time. I was able to ride the bike fairly soon after the second cast came off (6 weeks full casts, 4 weeks half casts), I even rode to physical therapy, but I couldn't turn it around or park it on gravel; that took another two weeks to build that strength and confidence, too.
As long as you are healing and knitting the bone (sometimes older bones take longer to knit), the bones grow back even stronger. I take it you didn't need any hardware for the repair? That's when folks overstrain the bones, since they aren't fully knitted and the hardware allows them to feel they are healed.