When my elderly dog, Luke, died, I couldn't stand being without canine companionship. I'd grown used to spending my days writing with a 120-pound Labrador retriever mix snoozing away at my feet, lying there like a big, white throw rug.

So I found the perfect replacement: a two-year-old Lab named Malloy. He is especially handsome: golden eyes, peanut butter-colored fur, a milk chocolate nose. By the time he'd spent two days lying around my office and gazing up at me adoringly, I was madly in love — and overjoyed that this pup was already as mellow as Luke.

Wrong. Malloy had worms, and once he got better, I discovered I'd fallen for a high-strung triathlete of a dog who needed lots of exercise to keep from bouncing off the walls. Those first few months I took him for so many walks that I lost several pounds. Not that there's anything wrong with that, but after all those long romps only one of us was exhausted.

Then I discovered the Chuckit! ($10, www.caninehardware.com for store locations), a simple plastic device that looks like an oversize spoon. With it I can hurl a tennis ball 150 feet, which makes for an incredibly efficient game of fetch. (Its ingenious design also lets you pluck the ball right off the ground, avoiding what even the most devoted dog lover never quite gets used to: the cold, slimy feel of slobber on yellow fuzz.) Now, after just 20 minutes of chucking and plucking, I have a pleasantly pooped pup, and plenty of energy left over for myself.

Martha Barnette is the author of Dog Days and Dandelions: A Guide to the Animal Meanings Behind Everyday Words ($25, www.amazon.com).