I had a great weekend at the annual JP Fitness Summit.

I was the first of three presenters. My topic was a triple geek-out on my favorite subjects: fitness, history, and politics. I explored how historical cycles not only influence our interest in health and fitness, but also the national leaders we choose -- for better and for worse.

Alan Aragon -- nutrition pro and singing sensation -- went after me, presentingsurprising and entertaining information about some hot-button topics. in his field. 

For example, he said an entry-level lifter might be able to add muscle mass equivalent to 2 percent  of his body weight per month. So a 150-pound male could pack on 3 pounds of solid muscle per month. Conversely, an advanced lifter (probably someone who's been lifting more than 5 years and is near his genetic peak in terms of strength and size) would probably struggle to add muscle equal to 0.5 percent of his body weight in a month. If he weighs 200 pounds, that's 1 pound of new muscle.

Women could expect to add about half as much muscle as men, Aragon said.

By pure coincidence, when I got back and checked my email I found a question from a reader regarding his body-fat percentage. As luck would have it, Aragon had addressed that very question. He said we only have two accurate ways to measure body fat: DEXA and dissection. (Only the first is considered appropriate for living people.)

Some people obsess over their body-fat percentage, but in reality it's one of the least important ways to measure your fitness and health, or to judge your progress on a diet or workout program. At the top of the list: how you look, how you feel, and how your clothes fit.

Aragon next tackled a more controversial topic: Is it possible for any of us to lower our body's metabolic "set point"? In other words, is it really possible to lose weight and keep it off, or will your body try to revert to its previous weight?

The key, Aragon said, is to keep the weight off at least 6 months. That's how long it takes for your behavior -- whatever you did to lose the weight -- to permanently influence your gene expression. (Some researchers have suggested that it takes 12 to 18 months.) The good news: Once your gene expression has shifted, it really is possible to live the rest of your life with a lower set point.

All of which is interesting, but vague. So let's get more precise: What specific behaviors help you keep weight off, and thus lower your body's metabolic set point?

Today's L.A. Times has the answer:

The National Weight Control Registry is an honor roll of dieters who have fought and won. Started in 1994 with modest expectations by [James] Hill and Rena Wing, director of the weight control and diabetes research center at Brown Medical School, the registry now provides some cherished data on how regular people have managed to keep weight off. The registrants, who are surveyed regularly, have maintained a weight loss of at least 30 pounds for at least one year.

Based on data from more than 7,000 people, Wing says there are few similarities in how people lose weight. But those who succeed in maintenance sing the same song.

Instead of trying to eat less for the rest of their lives to bridge the energy gap, these people exercise more. They typically spend an hour or more each day in aerobic exercise and strictly limit time spent watching television.

Physical activity, in ways that researchers don't really understand, influences some of the biological systems that promote weight regain, encouraging the body to become more sensitive to leptin and insulin, for example.

"Everyone thinks exercise is about burning calories," Fujioka says. "But you are actually returning the system to more like what it should be. Things start working again."

Once again, exercise is the answer to all the interesting questions.

Monday blog meat:

The highlight of the JP Fitness Summit -- and I think Alan Aragon would agree and not take offense at this assertion -- was Steve Cotter's presentation. Cotter is a "kettlebell guy," and the subject of kettlebells is so charged that you can start an argument among fitness professionals just by saying the word. You don't even need to add a verb or adjective. (You probably don't even need to enunciate the third syllable; given enough alcohol, "kettle" alone could start a fight.)

But Cotter made it clear he's more than that. He uses kettlebells to get desired training outcomes, but he doesn't wear one on his ring finger.

If you've seen Cotter's videos on YouTube (try this one for starters, then this one), you know he's an amazing athlete. (His background is in martial arts.) But he's also a terrific presenter, and a guy with a workout philosophy that emphasizes strength, mobility, and coordination over building muscle for its own sake.

Plus, I probably learned at least two dozen new exercises and techniques in a single afternoon. For someone who's been writing about fitness since 1992, and working out since 1970, that's really saying something.