on the bike it's more a matter of going out and riding, but about swimming you have to find someone who teaches you to, rather than putting on laps and laps

Yes you could. But you will have to add more flutter kick workouts to your swim regimen. Last year, I had major plantar fasciatis and could not run lots. So after my 2400 meter regular swim workout, I added 1500 meters of just pure flutter kicks. Yes that was 15 laps of flutter kicks with the snorkel. I got really intimate with each and every floor tile in the pool. After doing this for six weeks, I noticed that my cycling had improved tremendously and my quads and hamstrings didn't hurt as much as previous weekend group hammerfests.

p.s. I also ran a 3:41 NYC marathon two months later (with zero street miles).

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The short answer is yes, it is possible, but it really depends on what you need to do to improve in each sport and how much time you can commit to training with proper recovery. Are you still seeing improvements with your current level of bike training, and are you able to maintain that while also devoting more time to swimming? If you need to increase volume or intensity (or both) to improve on the bike, can you do that while also spending more hours in the pool? Assuming you have other life commitments (job, family, etc.), you have to ask what you can realistically accomplish in the time that you have. For most age-groupers, a two-sport focus is probably going to be a challenge because there are only so many hours in the day, but it all depends on your individual situation.

I have to respectfully disagree with the advice that you do lots of kicking. First off, I don't see that doing anything for you on bike. And even assuming kicking will lead to some marginal gains on the bike, which again, I highly doubt, you be much better off actually riding your bike for the 40-45 minutes that it will probably take you to do a 1500yd kick set. Now all that kicking will almost certainly help improve your swimming, but even there it's probably a low return on investment. Based on your goal swim time, most of that time you'll spend kicking is probably better spent just swimming more, or working on drills. This is especially true if most or all of your races are wetsuit swims. Good luck!