I usually let all of them out in the morning when I get up first . 20 minutes later they eat, then 20 minutes later I let them out individually, so there is no major activity. Free access to water. If they are exercising hard I give ice cubes, it seems to work and they aren't gulping down water and air. I only feed mine once a day(morning) in the summer. I resume twice a day as it gets colder and they aren't running around all the time. They get the same amount whether it's once or twice a day.
Misty- Samoyed Mix, Tannor- Golden Retriever CGC
Robyn- GSD CGC, TC, Midnite-GSD CGC,TC, Brennan-Golden Retriever CGC, Batman-Husky/Greyhound , Apollo-GSD