This is a post from staff writer Robert Brokamp of The Motley Fool. Robert is a Certified Financial Planner and the adviser for The Motley Fool’s Rule Your Retirement service. He contributes one new article to Get Rich Slowly every two weeks.

It’s that time of year — time to weed out all the stuff in the Brokamp household to get ready for the first yard sale of the season. It’s a great way to de-clutter, make a few hundred bucks, and sadly realize how many of the past Christmas’ presents are already collecting dust from non-use.

While culling the bookshelves, I came across Younger Next Year: A Guide to Living Like 50 Until You’re 80 and Beyond, which came out in early 2005. While I was still in my 30s when it came out, it was one of the first books that got me thinking about how I need to start taking better care of myself. After all, if I’m going to spend decades saving for retirement, I want to be healthy enough to enjoy retirement once I get there.

Unfortunately, as we age, we accumulate some aches and pains, don’t have the energy we used to, and eventually rely on Lipitor, Celebrex, or some other drug that sounds like the villain in a science-fiction movie. Well, that’s just part of getting older.

Or is it? Not according to Henry Lodge and Chris Crowley, the authors of Younger Next Year. According to them, 50% of illnesses associated with aging (e.g., heart attacks, diabetes) can be eliminated, and 70% of “normal” aging (weakness, sore joints, apathy — the stuff that makes you feel old) is not aging at all, but really decay. And it’s optional.

When the book was written, Lodge was a 46-year-old doctor and faculty member at Columbia University’s College of Physicians and Surgeons. Crowley was his 70-year-old patient, a former Wall Street lawyer who retired in 1990. Although Crowley exercised occasionally, he was 40 pounds overweight and feeling adrift when he became Lodge’s patient. Lodge explained to Crowley how Americans get good medical care (they receive treatment after something’s gone wrong) but not good health care (help with leading a lifestyle that will ward off disease and degeneration).

Younger Next Year describes that lifestyle, summarized by “Harry’s Rules.” Follow them, the authors say, and you’ll turn back your biological clock — “become functionally younger every year for the next decade.” From the book:

Harry’s Rules

  1. Exercise six days a week for the rest of your life. Don’t think of it as exercise. Think of it as sending a constant ‘grow’ message…as telling your body to get stronger, more limber, functionally younger, in the only language your body understands. Do it because it’s the only thing that works.
  2. Do serious aerobic exercise four days a week for the rest of your life. Hard aerobics, working up a good sweat, is our favorite exercise rhythm because [it] brings out our youngest and best biology: strong, fast, energetic, and optimistic all day long. Tell your body it’s springtime.
  3. Do serious strength training, with weights, two days a week for the rest of your life. Generally, we aren’t aware of nerve decay as we get older, but it’s the main reason our joints wear out, our muscles get sloppy, and our ability to be physically alert and powerful begins to fade. And it is reversible with strength training.
  4. Spend less than you make. Time to quit playing and come inside. Come inside your income. Try to do it early. As with smoking, you can recover. It takes time and earlier is better, but do it.
  5. Quit eating crap! Never go on a diet again. The only way to lose weight is to embark on a program of steady, vigorous exercise, avoiding the worst foods (french fries, almost all fast food, processed snacks with names that end with the letter “O”), and eating less of everything.
  6. Care. There have to be people and causes you care about. Doesn’t seem to matter much what the causes are. They don’t have to be important to society or make money, as long as they’re important to you.
  7. Connect and commit. There is a terrible temptation, in our 60s and 70s, to close up shop and narrow our lives. In most cases, retirement already does that, and it’s tempting to just go along with the program, get narrower and narrower. Well, don’t. It’s killing us. We have to exercise our social, pack-animal gifts as vigorously as we exercise our bodies. That means adding friends, doing more stuff, getting out there, and being involved.

But this isn’t just a fitness book; it’s about getting ready for, and getting the most from, retirement. It’s written mostly for over-50 men, but anyone can benefit from the advice. (Lodge and Crowley have written a follow-up book, Younger Next Year for Women.) The authors generally alternate chapters, with the doctor providing the science behinds his seven rules, and the patient giving the real-life, rollicking, often hilarious account of what it’s like to implement them.

Here’s the theory, in a nutshell: Due to evolutionary forces, humans are programmed to be active, eat certain foods, and remain socially connected. To do otherwise is to send a signal to your body that you’re ready to give up the ghost. “Your body and brains are perfect for their natural purposes, but none of them was designed for modern life: fast food, TV, or retirement,” writes Lodge. “In a paradox that you absolutely have to understand, endless calories and lack of exercise signal your body that you’re heading into a famine that you may well not survive, and in response, your body and brain head into a low-grade form of depression.”

Follow Harry’s Rules, and you can keep growing, remain energized, and stay physically and mentally mid-life long into your twilight. “Biologically, there is no such thing as retirement, or even aging. There is only growth or decay, and your body looks to you to choose between them.”

This is one book that will not make it into the Brokamp family yard sale. However, if you’re looking for a used bunk bed, impulsively bought juicer, or men’s Superman underwear (only worn twice – my wife hates them), then stop by our yard sale in a couple of weeks.

This article is about Health & Fitness, Retirement