I did a local half marathon and then the Disney half back in 2013 with some intervals but not a whole lot since so I just finished the C25K program trying to get back into it. I *really* want to do my first sprint triathlon this summer; sometime in August. The local half/full marathon in the second week of October. It would be my first full marathon.
Is it feasible/realistic/survivable to go from 3-5 mile base now to a full marathon by October or should I do the half? I just want to be able to finish my first one alive. Is it a bad idea to try to add in biking & running to train for the sprint as well?
Can you do it? I think yes, if you stay mostly injury-free you'll be able to train & finish.
Should you do it? That depends. Here are some things I would think about...
- Are you injury prone?
- Do you have the time to dedicate over the summer to 3 sports (tri) plus increasing long runs? (I've never done a tri, but I'm sure fitting in all the workouts can get challenging.)
- What's your farthest distance so far? If you've done several half marathons or similar distance I think that's a better place to start than if you've only done 5K to 10K races.
- Do you want to do it? Obviously you're thinking about it, but is it something you really want or just something you feel you "should" go for at some point?
A strong half marathon is a good goal too, so just think about what makes the most sense for you right now. Maybe it's the full, but if not the marathon will wait for you until the timing is right!
Honestly? I think you'd be better off doing the half. That's a huge jump in mileage. I really think that to tackle a full, you want to have at least a 25-30 mpw base when you start training, which should be probably in June for an October marathon. If you really really want to do it, I think it is possible. I just feel like the full marathon distance merits a lot of respect because it is truly very tough, and you may not be in the best place training-wise to jump right in.