Following an Olympic champion's training routine is not a bad idea if you don't expect it to make you an Olympic champion! It might be a great improvement on your current training routine though, if you're interested in the sport at all.

The physical (and genetic) demands of athletics aside, we were talking about writing. Just starting on a lark is what worked for Haruki Murakami. Again, it's very unlikely you'll be the next Murakami. But at least you'll improve a lot at something you find interesting! What is the downside here, exactly? Unless you're an opportunity-cost-minimising, industrial-output-maximising kind of person. That's fine, but that's not everyone.