She has the toning that comes from yoga, pilates, strength and conditioning training. Her legs and arms are slim yet extremely muscular. I would say she is very very fit. As for diet, I would presume a lot of fish, salads, maybe grilled chicken/turkey if she's not veggie and a thimble of sherry at Christmas. You don't get a flat tummy like hers guzzling wine every evening.
About a year ago I had a similar figure, though I'm 4 inches shorter. Now I look like Homer simpson. I even have fat on my back
.
I'm only 3 weeks back exercising though after a period of doing absolutely nothing for 9 months due to depression. Slowly building up some strength again but not shifting ANY weight whatsoever. It's disheartening.
My two vices are alcohol and dark chocolate. I also smoke 
It takes so much self discipline for me to get a body I am content with. On days where I have loads of energy and am not tired, I'm enthusiastic, disciplined and workout and then walk everywhere.
If I'm tired, I tend to do fuck all, then hit the bottle and then feel like shite the next day........ 
I love her figure. She has a strong but lithe build. She's not emaciated at all. She has really strong thighs. Her upper arms are very toned, her stomach is flat, she has a naturally tiny waist and doesn't carry weight on her boobs.
She looks great for her age.