Dennis Quaid has stayed in great shape in his 60s by always maintaining an exercise regime.

The 63-year-old actor got into working out in his 20s and would stay fit by boxing and his commitment to fitness was borne from a piece of advice he was given by super-fit 50 year old.

In an interview with the new issue of Men's Fitness magazine, he said: ''I used to box when I was in my 20s. There was this guy at the time at the Hollywood Y, who was in incredible shape in his 50s. I asked him that same question. 'How do you do that?' He told me, 'You take care of yourself in your 20s and 30s and the rest will take care of itself.' He was right, it doesn't mean you have to be there every day, but you do have to live your life with that in mind. Because if you let it go, every time it gets a little harder to get back. So I've always stayed with it.''

The 'Innerspace' star likes to stay fit and active by working out regularly and these days he likes to cycle and do yoga to stay healthy.

Quaid - who is dating model Santa Auzina, who is 32 years' younger than him - said: ''I genuinely enjoy it [exercise], I was a runner for about 35 years, but that gets hard on the knees and the joints. At least for me. So I turned to cycling, which I'm currently doing. That and yoga. Along with that, you got to still get into the gym and lift. Do the sit-ups.''