Adding in my experience since it's somewhat similar. Used to race Xterra and 70.3s decently well (went to WCs for both), switched over to bike racing shortly after first kid. Now have 2 kids, aged 3 and 5, race bikes as Cat 2. But the catch is I'm pulling the plug after this year to spend more time with the family.
In general your fitness will get you through cat 5 and 4 pretty easily where you can ride away from the field. In the 3s you'll need race acumen, which you may or may not have, as if you miss the moves there is very little that loads of fitness will do for you. Especially if you're tall/big, people will wise up quick and suck your wheel at every race only to come around you at the end with a kick.
Crashing is definitely a possibility, but not a requirement. I've seen people hit the deck tons, and retire from racing as a result, whereas I've maybe ended up with minor road rash in a handful of falls over the past 4 years, so YMMV
But back to time commitments of 1 sport vs 3, I don't necessarily find bike racing to actually save you that much time as you end up racing a lot more (10-20 races a year) and the drive+race time of each (road races will be ~3hrs) eats up close to the entire day on many many weekends out of the year. If you want to trim back time and be competitive in a sport, I would recommend running (trail running maybe) instead.
In general your fitness will get you through cat 5 and 4 pretty easily where you can ride away from the field. In the 3s you'll need race acumen, which you may or may not have, as if you miss the moves there is very little that loads of fitness will do for you. Especially if you're tall/big, people will wise up quick and suck your wheel at every race only to come around you at the end with a kick.
Crashing is definitely a possibility, but not a requirement. I've seen people hit the deck tons, and retire from racing as a result, whereas I've maybe ended up with minor road rash in a handful of falls over the past 4 years, so YMMV
But back to time commitments of 1 sport vs 3, I don't necessarily find bike racing to actually save you that much time as you end up racing a lot more (10-20 races a year) and the drive+race time of each (road races will be ~3hrs) eats up close to the entire day on many many weekends out of the year. If you want to trim back time and be competitive in a sport, I would recommend running (trail running maybe) instead.