Winter training

I did the Jorge M plan several years ago.  I went bike-focused and followed the program as outlined 4 days a week and just did hour-long Z1 runs two days a week (I don't remember if I did any swimming or not).  I lost a lot of run fitness during those four months but in the spring when I started running again the run fitness and speed came back quickly and in 8 weeks I was running as fast as I ever had. 

My cycling has progressed a lot since I did the Jorge M plan so if I were to do it again (and yes I am considering it), I would want to maintain running and swimming.  

I am currently looking at doing a March 5th marathon and after stewing over different plans for the past two weeks I am thinking that 4 days of running, (1-shorter recovery, 2-medium long tempo/interval, 1 long run) with two bike days (1- medium long tempo/interval, 1-long endurance), and two swim days (1- medium on the day of the short run, and 1-medium long).  You could do something similar If you swapped out the running and cycling.  That would put you at 4-days on the Jorge M plan, 1-medium run, 1-long run, 1- medium swim, 1-medium long swim).  That should achieve a good bike focus while maintaining running and swimming.  

Yes, three rides is enough to make progress.  There is an old thread for this program HERE.  Jorge made some sugestion in the thread on what days to skip for a modified 3-day plan, etc. ou Y might want to start a new thread and see if a few other people will do the program with you so everyone can discuss each week's work. 

My standard weeks are two had rides and a long ride.  During standard weeks my two hard rides and indoors on a bike trainer and the long ride outdoors.  During the winter my long rides tend to be indoors too.