Just keep trying to get good nutrition ,adequate rest and exercise and your body will adapt to whatever is optimal for what you want to do with it. Pump iron all day and it will develop large muscles good for pumping iron and possibly not much else. Run or cycle all day and your body will develop into the most efficient machine it can to run or cycle all day. One thing to watch out for is society's view of what is healthy. That view continues to change and I fear most of it is driven by profit rather than health benefits.