That's pretty cool... I wonder what his dieting was like. Yoga won't do that alone.
I've wanted to do something similar, but the other way. I used to be beyond active, strong, and fit. About halfway through my Naval career I basically quit. I get winded far easier now and I can barely lift any weight.
I keep wanting to get back in shape and gain about 25lbs of muscle (while dropping about 15lbs of fat), but it's starting that seems to be the hardest.
I used to do Muay Thai and Brazilian Jui-Jitsu but I can barely do the warm-up these days. Maybe it's time I get off my lazy ass.