One fine day last autumn I clocked out for lunch and just did it: I walked briskly across my company’s parking lot and down the street to the stop sign and back, then I went back into the building and ate lunch. The walk took ten minutes. I know from previous experience that I can walk a mile in twenty minutes if I hustle, so I knew I had walked about one-half mile. Later, I verified the distance with my car’s odometer.

The first few days, I had to force myself to head outside into frigid air instead of to the refrigerator for my sandwich. I have a sedentary job, and the habit of sitting tends to build upon itself. But the more you do, the more you can do, and after a week or so, I found myself craving the fresh air and the invigorating feeling I got from using all those muscles just as much as I craved my lunch once those hunger pangs began. I found, in fact, that putting off lunch for those ten minutes was easy, since I was exercising instead of giving in to my appetite. Ten minutes is nothing to your body. It doesn’t matter how hungry you think you are, you will make it through those ten minutes.

I kept it up through the winter, skipping walks only when it was raining or sleeting, and when that happened, I chafed at the inactivity, sometimes substituting some simple exercises in the corner of my workspace instead. I’ve been walking nearly every weekday for about ten months, and recently I’ve added a second walk in the mornings, when I arrive at the office early enough. Ten minutes of brisk walking a day isn’t enough anymore. It never was.

Last February I had my eyes checked, and the optometrist saw something in one of my eyes that prompted him to tell me to get my cholesterol checked. I did. It was 250. This is bad. My doctor said that for the present, I should try to diet and exercise it down, so I began avoiding saturated fats and cutting down on sweets, and hiking down and up the road before lunch with renewed vigor. There’s not much else I can do to improve my diet: I eat oat-based granola--homemade without oil--almost every morning. I eat whole grain products most of the time, and lots of fruit and vegetables. We don’t eat out often. I cook.

Oddly, what frightens me most about having a high cholesterol count is the medication I might have to take to control it: I don’t even know its name(s), but every single older person I know who is on it is forbidden to eat grapefruit. I don’t know why, I just know that grapefruit eaten in combination with that type of medication can kill you. What a horror! I love grapefruit. Few foods satisfy me more. Do you want a non-fattening, utterly-filling accompaniment to your brown-bagged sandwich? Take a grapefruit to work in that bag. After you finish your sandwich, go stand over the shop sink and peel that big honking citrus. Rip the sections apart and bite into them. What a sensation! I don’t want to give that up. Why, oh why couldn’t it be mangoes that are contra-indicated with those drugs--something I wouldn’t mind living without?

But I know my daily walks can only do me good. Since I invariably take a walk at noon, I’m getting some exposure to strong sunlight, allowing it to manufacture vitamin D out of my body’s supply of ... cholesterol! Yes! That’s what it does. Did you know that? That’s the reason our bodies make cholesterol—it is fuel for making vitamin D. Therefore, if you think hiding from the sun is going to keep you healthy, think again. Unless you have already had skin cancer, or there is a history of it in your immediate family, you will probably benefit from moderate exposure. Ten or twenty minutes won’t kill you, and it may help in more ways than you might think. Visit the Mayo Clinic website for more information.

I have additional tactics to get more exercise into my overly-busy life: whenever I have a choice between taking stairs and taking an elevator, I take the stairs. When I go shopping, I choose a parking place as far from the door of the store as I can find. It all adds up. Whether negotiating stairs or parking lots, I don’t amble, I don’t mosey—I walk quickly. I recently visited my parents in their retirement community. One evening, we were heading over to the dining room and the elevator already contained two elderly people in wheelchairs. My dad joined them, leaning on his walker, and Mom suggested that she and I take the stairs. “I plan to use the stairs as much as I can—while I can,” she admitted as we descended. Good strategy. Remember: the more you do, the more you can do.

Walking for exercise couldn’t be easier or cheaper: all you need is a supportive pair of shoes and a little time. You don’t need equipment, or special clothing, or membership at a gym. You need only your intent, your shoes, and somewhere to go. Just get out there and move.

Read more about staving off poor health by moderate exercise and easy diet changes here. The doctors who contribute to RealAge.com are a bottomless well of tips on fitting exercise into daily life, as well as tasty, healthy menu and recipe ideas.