Running magazines are great for recommending one-type-fits-all diets for runners, but they are dead wrong and their O blood type readers who follow their advice will not benefit from their recommendations.

I used to swear by the advice of running magazines, and now I swear at their diet advice, especially regarding diets for runners.

Editors of popular, nationally known running magazines simply do not understand or acknowledge the correlation between blood types and their food reactions; if they did, they would amend and expand their advice to runners of different blood types about what they should be eating.

I know, I tried and I failed. All I did was gain more weight as I ran more and more miles to lose weight. No wonder I was frustrated and unhappy with my excess weight gain.

I have sworn off all wheat products and simple sugars found in cane or beet sugar (sucrose), and I am dropping weight and feeling much better. Natural complex sugars found in honey and fruits (fructose) are OK.

Because I am a Type O I also learned that Type O stomachs are more acidic than alkaline. Type Os are the only blood type that have the acid to digest and break down lean beef products because of their lower pH factor, the other blood types are alkaline and consequently should not be eating beef.

Just because O blood types have the acidic stomach to break down meat and digest it better than other blood types does not mean you should feast on 16-ounce steaks every night. Eat no more than 6 ounces of beef at any meal.

When I learned that according to Dr. D'Adamo healthy Type Os are meant to reduce stress and relax by doing intense physical exercise, I knew he was on target. I relax by running 6 miles; my wife, who has Type A blood, reduces stress and relaxes by being still and calm, clearing her mind and doing nothing.

Few people realize that it is not the stress itself that bums us out, but our reaction to the stress in our environment that depletes our immune systems and leads to illness.

Unlike our ancestors who faced intermittent acute stresses such as the threat of predators or starvation, we live in a highly pressured, fast-paced world that imposes chronic, prolonged stress. Think of your one-way, one-hour commute in rush hour traffic or the pressures of constantly meeting business deadlines.

Stress-related disorders cause 50% to 80% of all illnesses in modern life, according to D'Adamo.

A regular, intense exercise program helps Os maintain weight control, emotional balance and a strong self-image.

Here is another scary fact: Type Os who do not express their physical natures with appropriate activity in response to stress are eventually overwhelmed during the exhaustion stage of the stress response.

This exhaustion stage is characterized by a variety of psychological manifestations caused by a slower rate of metabolism, such as depression, fatigue or insomnia.

I have gone through periods where I stropped a training program, and while I seldom if ever felt depressed or fatigued, I have not slept nearly as well as when I was younger. It was common for me to wake up 3 or 4 times a night without being able to sleep through as I did in my youth.

For Type Os who are not runners, you should know that to achieve maximum cardiovascular benefits from aerobic exercise, you must elevate your heartbeat to approximately 70% of your maximum heart rate.

One rule of thumb for determining your maximum heart rate is to subtract your age from 220, thus a normal 60 year old would have a maximum heart rate of 160. A runner in good condition could easily have a higher maximum heart rate.

Once that elevated heart rate is achieved during exercise, continue exercising to maintain that rate for 30 minutes. This regimen should be repeated at least three times a week.

(Editor's Note: This is Part 4 of a 5-Part Article.)