You have a mix of 2 active breeds. 2, 20 minute walks isnt enough for most dogs/breeds, even the lazy couch potato ones. And if you are walking your dog on a lead at your pace then it most definitely is not enough, neither mentally or physically. My 17 year old shih-tzu got more than that, and she was off lead the whole time.
I feel your pain though. I have a 2 year old Jack Russell, we go to the beach every morning for 2.5 hours, all off lead, so he can go at his own pace, and then a 60-90 minute off lead walk every evening. This is 7 days a week, i have not, and will not miss these outings for him every day. One bonus is that he keeps me fit too, he's like my own personal trainer.
I feel your pain though. I have a 2 year old Jack Russell, we go to the beach every morning for 2.5 hours, all off lead, so he can go at his own pace, and then a 60-90 minute off lead walk every evening. This is 7 days a week, i have not, and will not miss these outings for him every day. One bonus is that he keeps me fit too, he's like my own personal trainer.