When you are doing endurance swimming you just need to take in as many carbs as possible to put on as much weight as you can. Basically you can eat whatever you want, which can be quite fun. Everything is guilt-free.
At least for soccer players, it comes down to a blend of two types of fitness - your base endurance, which comes from longer distance running, and your speed, which comes from sprint-based workouts.
When I was younger, I used to wrestle, and I feel that it contributed to my athletic ability because as a wrestler you have to be an all-encompassed athlete. You need stamina, strength, endurance and mental capacity. You also have to learn how to adapt in any situation.
Adventure books are my personal favorites. 'The Endurance,' a story about Ernest Shackleton's legendary Antarctica expedition, or 'Into Thin Air,' Jon Krakauer's personal account of the 1996 disaster on Mt Everest, are two notables.
Humans are built for endurance, not speed. We're awful sprinters compared to every other animal. We try to run our races as if they were speed races, but they are not. They're endurance races. Even a marathon, the way it's run now, it's not an endurance contest.
I hate doing Tabatas - you do whatever you want at high intensity for 20 seconds, and then get a 10 second break and you repeat that for 8 minutes. So you can do jumping jacks for 20 seconds, you can do sprints for 20 seconds, etc. It's supposed to help you get your endurance up really fast.
My school career was absolutely crucial to me. As an endurance athlete, some of the most important years are maybe when you are 16, 17, and 18. For me, getting that right was very important, and my school allowed me to do that.
I don't know whether endurance sports attract obsessional people, or training for endurance sports makes people obsessional... it's the chicken and the egg.