My mention of domesticated animals was in response to you asking if humans could guide evolution. These animals are examples of artificial selection (as opposed to natural selection which occurs in nature) because the humans who domesticated them were selecting for (keeping and favouring offspring with) certain traits such as docility, easiness to train, fat/muscle content, size, quality and quantity of milk/eggs/wool, strength, loyalty, and others. These are largely influenced by genetics, and since molecular evolution is defined as heritable change through changes to DNA, what we did to these animals can also be classified as guided evolution. What happened to pigs wasn't just a 'lifestyle' change, it had direct consequences for their heritable material (DNA) because humans were so clearly breeding them to display certain traits more than others, essentially favouring certain DNA sequences over others.
I said nothing about sexual lifestyle so don't say I did. That will wait for a different post since I have some things offline to attend to this morning. And you are also conflating changes in lifestyle with evolutionary consequences. Please don't.
You may be confusing physical fitness with evolutionary fitness. Physical fitness refers to size, strength, endurance, and so on; it is acquired and influenced by an organism's level of physical activity. A dog (or human) who runs a lot will be more physically fit than one who lies around all day. Evolutionary fitness is entirely different: the ability to survive to reproductive age and produce offspring who can do the same. It is often influenced by physical fitness to escape predators, but an evolutionary fit organism does not inherently depend on physical fitness to exist. Likewise, a physically fit organism could be sterile and therefore have low evolutionary fitness.