Treadmill exercise for senior dog, part 2

I feel elated.
On our second dog training session Tete got on the treadmill on her own, just by the lure, with more confidence. We are more than halfway there.
Here is the brief story: Tete is a 6-year-old shepherd mix female dog that has been gaining weight since the family moved from California to Arizona; because of the heat and their busy life, they can't keep up with their habitual daily walks outside and asked me to teach Tete to walk on the treadmill so she can get more exercise and keep a normal weight.

On our first session I noticed that she was not only uncomfortable getting close to the treadmill while it is turned off, but the sound of her nails scraping on the mat unnerves her. We worked on giving her more confidence and she kinda sorta did, she could walk on the treadmill sideways, putting her back legs out of the machine and her two front legs walking for a couple of seconds.
Today I sat on the end of the treadmill with hot dogs and asked her to get on, "súbete" in Spanish, without touching or pushing her in any way so she could get on on her own time. She did, so I flooded her with rewards to create a powerful pleasant experience with this exercise on the machine.
Eventually she got so tired that sometimes couldn't lift her back legs to get on the treadmill, so I gave her a break and after 10 minutes, tried it one more time for success and rewarded her.
She still has some way to go, but it's a big advance, since we are working not on a trick (get on the treadmill) but on her confidence, losing fear, assessing her independence.
She is smart. She will get there.
This is a follow-up to "Treadmill exercise for senior dog".