I think you mean "catabolic"
It is possible that you can over train and force your body to start to consume muscle tissue as an energy source.
It really depends on you and your body..
Some can run 5 miles as a warmup and for some 5 miles can seem like a marathon.
No 2 bodies are going to react the same way.

I dont suggest you do do leg lifting on the same days as intense running or riding....