I walk Athena and my husband walks Sinister every night together. But if my husband can't go I choose a dog to go with me. If I am taking my kiddos to the playground I take both with me just fine. Both my dogs are leash trained, I would never recommend walking both if one is not leash trained and one is dog reactive. Exercise come in many forms for a dog. If you can't take both everyday for a walk play with the one that does not go with a flirt pole. The flirt pole does a way better job tiring my dogs out in a shorter amount of time than just a walk.
Athena- Long Coat GSD -CGC
Sinister Black- GSD