Walking is always good and anyone can do it anywhere. Even better if you can find a hill to go up and down. Find a stadium or other outdoor place with many stairs, go up and down, carry a water bottle in each hand. 30 minutes will be a veru good workout on stairs.

I walk my dog and collect aluminum cans while I do. My rule is I have to fill one Walmart bag with crushed cans. Everytime you pick one up, do a squat. I used to be really trim when I did this. My walks got longer and longer and my goals changed until it was "30 cans" etc.

Nice idea to do the can pick up, but in NYC you could probably find 30 cans in about 5 minutes. Catkim has a great idea but be careful going down the hills and steps.

When my father was 50 he had a heart attack. Doctors said to do some aerobic exercise but that generation didn't get it. I was about 18 and figured I better take precautions so I started running and did several miles a day for about 30 years until last autumn when I was in Lake Tahoe and I ran down a mountain. Halfway down I got shooting pains in my right knee and could hardly walk for a few days. I tore the cartilage and decided to take some time off. Now I bike for about an hour a day but it's not the same. But every doctor I talked to said that going downhill or down stairs is harder on your knees than going up. So by all means do it - but take it easy on the down side even tho that's where you feel like going fastest.

Anyhow, incorporating some daily exercise into your life is a great idea at any age. good luck to you.

I have a 30-minute workout to develop my 6-pack abs. With my strong work ethic, I can now finish one in 25 minutes. And my abs have developed to the point I can rest a can on them leaving both hands free to garden.