These days, it's easy for people to get confused about exercise -- how many minutes a day should they spend working out, for how long and at what exertion level.

Conflicting facts and opinions abound, but one Mayo Clinic physician says the bottom line is this: walking is good, whether the outcome measurement is blood pressure, diabetes, cardiovascular disease, joint problems or mental health.

"Getting out there and taking a walk is what it's all about," says James Levine, M.D., Ph.D., and a Mayo Clinic expert on obesity. "You don't have to join a gym, you don't have to check your pulse. You just have to switch off the TV, get off the sofa and go for a walk."

The health benefit associated with walking is the subject of Dr. Levine's editorial in the July issue of Mayo Clinic Proceedings . Dr. Levine's piece is entitled, "Exercise: A Walk in the Park." and accompanies a Proceedings article that showcases the merits of walking as beneficial exercise.

The study, undertaken by physicians from the Shinshu University Graduate School of Medicine in Matsumoto, Japan, determined that high-intensity interval walking may protect against high blood pressure and decreased muscle strength among older people.

Over five months, the Japanese researchers studied 246 adults who engaged in either no walking or moderate to high-intensity walking. The group who engaged in high-intensity walking experienced the most significant improvement in their health, the researchers found.

In his editorial, Dr. Levine says the study lends credence to the notion that walking is a legitimate, worthy mode of exercise for all people. Dr. Levine says it's a welcome message for his patients, who fight obesity and appreciate that a walk is one way to improve their health.

Unlike a health club membership or personal trainer, walking "is there for everyone," Dr. Levine says. "Walking doesn't cost you anything, you can do it barefoot and you can do it now, this minute."

"Sitting is bad for cholesterol, it's bad for your back and muscles," Dr. Levine says. "It's such a terrible thing for our bodies to do and the less of it you do, the better. But activity is not easy. If it were easy, everyone would do it."

Authors for the study in Mayo Clinic Proceedings on high-intensity walking were Ken-Ichi Nemoto; Hirokazu Gen-No, Ph.D.; Shizue Masuki, Ph.D.; Kazunobu Okazaki, Ph.D.; and Hiroshi Nose, M.D., Ph.D., all from the Shinshu University Graduate School of Medicine.

A peer-review journal, Mayo Clinic Proceedings publishes original articles, reviews and editorials dealing with clinical and laboratory medicine, clinical research, basic science research and clinical epidemiology. Mayo Clinic Proceedings is published monthly by Mayo Foundation for Medical Education and Research as part of its commitment to the medical education of physicians. The journal has been published for more than 80 years and has a circulation of 130,000 nationally and internationally.