It is generally good to train the top end, but it doesn’t sound all that complimentary to me unless you’re aiming to beast the ride itself, or it’s a particularly hard parcours. It’s 200 + miles at Z2, afterall. But if you think you’d enjoy it and it keeps things fresh, then why not? Only thing I’d be wary of is that it might end up as basically boxercise. You see professional fighters, MW and above, gassing out in fights – i.e. cumulative 3min rounds of boxing are absolutely devestating and far beyond what the enthusiast is capable of, so how serious can the training be just dipping your toe in?
What does this mean – My legs and cardio should be fine, it’s my ability to support my own weight that worries me.
So your engine’s fine, your legs are conditioned such that you’re not going to cramp in the first 100 miles or have some sort of muscle problem, but you’re worried about supporting your own weight??? You’re sitting on your aris – the bike’s got you taken care of here.
I’ve heard of ultra long distance cyclists having issues with just keeping their head up to look down the road, as their shoulders and neck are hammered. But that is orders of magnitude beyond what you’re talking about here – 200 mile ride won’t put you in that sort of distress.