Arcus, every elite archer should have a training schedule that they follow. I think when we hear about shooting "every day", they often mean "almost" every day. It sure seems like every day, but rarely it is. Most training schedules will have archers shooting 4-5 days/week, then working on other things the remaining days like cardio, strength, technique or mental preparation.
That's how I'd set it up if I had the choice.
If all I did was archery, I'd want to shoot 100-150 arrows one day, 200-250 the next, then take a day off from shooting, then 200, then 150, then take two days off. Every now and then I'd probably throw in a 300+ arrow day, but I personally don't think that numbers are so necessary, esp. in the days of 3 arrow ends and the set system. Nowdays, technique, equipment and mental preparation are more important than sheer endurance IMO.
Even full time archers need something else to do. It doesn't take all day to shoot even 300-400 arrows. Usually, the archers are shooting a lot of those at close range/blank bale, or are shooting 10-12 arrow ends and can shoot 100 arrows in less than an hour. I do this all the time when I'm training, usually shooting 9 or 12 arrow ends to cut down on the wasted time of walking back and forth to the target, and to build up my endurance. That means I can shoot 100 arrows in just 11 ends or less, which I can easily do in an hour. This past Tuesday evening, I shot 200 arrows in less than two hours. Today, I'll likely shoot 100 arrows in about an hour.
So even if a "full time archer" is shooting 300-400 arrows in a training day, that leaves 1/2 a day for them to do something else.
At full effort, training an archer is barely a part-time job, unless you include travel time to tournaments.
John