Yes, I'd noticed for some years how much less cycling is dependent on a good body shape.
For peak performance things are different obviously. A well known illustration of that is Jan Ulrich, Lance Armstrong's long time rival in the Tour de France. Jan would famously put on huge weight every year between Tours, appearing sometimes only a few weeks before a Tour looking gross and as though he would have no chance of entry.
But he was always magically able to shed it quickly and turn up looking like a different person on the day. The one big difference between him and other riders was that he always had a famously slow pedal cadence ability, much slower than any other pro, something of a fatter man's characteristic retained into his temporary leanness.
That age thing applies in many physical sports. Medics have for years considered that the peak is about 28 years old, so it seems that as we recede from the peak, we are no longer able to accept a reverse of the long climb to that peak level. I think that's more of a psychological than physical thing, an inability to mentally accept less than we once knew and experienced. Acceptance that one is growing older is painful, no matter how much we deny it.
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