A single-sport focus in the winter is a good idea, but going after another tough endurance race may not be.
The off-season is a great time for some single-sport focus and to work on weaknesses—something you may not get to do during the regular season while balancing all three sports. That being said, you need to make sure you don’t overdo it— this is a time to get refreshed both mentally and physically.
I like to schedule a half marathon, a 10K, or a 5K into my athletes’ preseason training to get a nice gauge of fitness and to give them a carrot to keep the fire lit early on. If an athlete was seeking a PR in the marathon, it would fall under the bucket of regular-season training because it would take so much effort and time to really do it right. Only after that race could the off-season really begin.
A coach has to be careful with an off-season marathon program because an athlete can only go hard, day in and day out, for so long before mentally and/or physically wearing down. You need to take the off-season seriously by greatly backing down the training, so you can get the most out of your training and racing during the next race season. The best plan is to work that standalone marathon into your regular-season schedule; go for it when you can have a smart, appropriate training progression leading into the race. Take your off-season off, and enjoy it without the stress of focused training or performance goals.
Jim Lubinksi is the head coach at Red Performance Multisport. He is also USAT and Ironman certified, a Training Peaks Level 2 coach, a professional triathlete, and a host of the Tower 26 Be Race Ready podcast.