But the talk all day was about mick jagger, almost 70, with the energy of a 30-year-old. So, we wanted to know his secret, and abc's bill weir spoke with the rolling stone. ♪ Reporter: You've... See More
But the talk all day was about mick jagger, almost 70, with the energy of a 30-year-old. So, we wanted to know his secret, and abc's bill weir spoke with the rolling stone. ♪ Reporter: You've heard of dog years? Well, this is what age 69 looks like in stones years. ♪ Jumping jack flash ♪ ♪ is a gas, gas, gas ♪ Reporter: And before you dismiss mick jagger's energy at last night's sandy benefit as a two-song fluke -- ♪ ♪ hey, you ♪ Reporter: Know that in recent weeks he has been ripping up the stage like this for two and a half hours a night. How do you do it? I was sore the next day from watching. How do you do it? It's what I do, really. ♪ Take a drive downtown ♪ Reporter: People are willing to pay, you know, $500, $600 for a seat, just think what they would pay for mick jagger elixir, your fitness regimen. I don't really have much of a fitness regiment to be honest. I mean, I do have one -- Reporter: Yes, a band with an average age older than the supreme court rehearsed eight grueling weeks to play just five shows, a work ethic that somehow survived all those years and miles, women and drugs. Keith richards still enjoys a drink or three, but ronnie woods has been sober for years, and admits this tour is a real test of willpower. We hit them with clarity and focus now. Before, it was eyes down and meet you at the end, you know? And like, "oh, no. How am I going to get out of this?" A little bit of that still goes on. Reporter: So, despite the struggles for sobriety and band harmony, they've discovered their real secret is simply doing what they love. Retirement would be a death sentence. And there's no better fountain of youth than an arena full of adoration. People say, "well, why are you still together?" And I say, "well, it -- because people like us." Of course, we love playing. But you have to have both of the part of the equation. Reporter: So, for those inclined to order saturday's pay per view finale with bruce spring teen and lady gaga, thinking this could be the last time, keep in mind the tour is called "50 and counting." Bill weir, abc news, new york.
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