My basic question is, how long should I give a change from dedicated XCO to dedicated XCM in a training plan to reap the rewards?
in 2017 and 2018 I focused on XCO, but this year I moved - since November 18 - to be dedicated to Marathons. This is because I’m not a powerful rider with a low FTP and err toward endurance. I did enter Marathons in 2018, and in 2019 I’ve felt - unmeasurable - changes in my muscular endurance and sustained power, although not my FTP. I’m top 25% in the Vets results - just -but not troubling the podium.
I’m wondering, whether to revert to XCO, or give Marathon training & races more of a chance to develop?
Not sure what your asking here. What plans have you been doing (ie: short power build) and what plans are you currently doing (ie: Sustained Power build)? If you’ve gone through SSB1 & 2 and finished SPB or GB, I’d say you’re moving in the right direction. Then as you move onto XCM Specialty you will be further dialing in your fitness.
So I guess I’d say between 8-16 weeks (Build and Specially) you should be fit for the demands of XCM. That is if you’ve been consistent and your volume (TSS) is enough to further adaptations based on your history and what you can handle.
Sorry I haven’t made that clear. What I’m asking is, have I given myself enough time to adapt to XCM, or, if on a year by year basis I’m flipping between XCM and XCO training and racing, am I never giving myself time to excel at one of the disciplines?
1 year of anything won’t have you excelling. XCO and XCM aren’t too far off regarding fitness demands, so you can train and race for both (as I do), then specialize with XCM leading into your A event . You see many XCO riders excel in XCM and stage races as well (Nino Schurter and Henrique Avancini). The goal will always be to raise your base fitness and FTP, then build/specialize from there.
If you stick with General Build after SSB1 & 2, as opposed to Short Power Build (XCO) or Sustained Power Build (more XCM-ish) you will be fine swapping races between XCO or XCM. I’d say race both the same year as C and B priority races, then specialize towards an A event whatever discipline you choose. XCM becomes more about pacing and mindset as you’re on the bike for much longer than XCO.
So in short, no, swapping between disciplines will not be detrimental to your fitness gains and will likely make you a fitter athlete. Not to mention keep you motivated and interested.