I do the exercises found at
Matt Furey - Zen Master of the Internet
I cannot recommend this regimen enough because it is the most effective workout I"ve ever done, and it takes only 5-10 minutes.
Even newbies who may be only able to do 10 hindu squats, 3 hindu pushups and barely get into the neck bridge stance, will notice after 1 week they feel great, and are getting stronger.
This may sound like shilling for Matt Furey, but, I am getting results.
I do 200 squats a day, and 100 pushups currently. I go for walks a lot too.