Friel's book is way technical and written more for those with racing aspirations. His diet advice works for me but a lot of people (including Ed Burke RIP) disagree vehemently with it. Training depends on what your goals are. Do you want to lose weight, get faster, ride longer, get real fast, ride real long? There is no one size fits all.

I have a couple of dozen cycling books. Some of the best are by Chris Carmichael, Ed Pavelka, Fred Methaney, Arnie Baker and Ed Burke.

I like what Coppi said "Ride your bike, ride your bike, ride your bike."