The flapping sound was getting a little annoying.

But I kept going, determined to make it the rest of the way. After about a year’s worth of mileage, my old running shoes were breaking down.

The black tread, which I had glued back on not too long ago, had broken loose again. I decided it was probably time to get another pair.

But I wondered what kind of technology shoe manufacturers were coming up with these days to make me run faster and longer and with fewer injuries.

A long way

Manufacturers have improved running shoes significantly since Dick Wilson ran track for Kansas University in the early 1950s.

“It’s amazing what they’ve done with shoes,” said Wilson, who, at 70, is something of a running shoe expert.

He’s been selling running shoes in Lawrence sportswear stores for the past 10 years, and he’s been running competitively for the past 25 years. Wilson was rated nationally last year as the No. 3 runner in the men’s 65-69 age group.

“When I was running for KU 50 years ago, all we had was a canvas top and the bottom was a piece of blown rubber on the heel and another piece of blown rubber on the forefront,” Wilson said. “There was no support and hardly any cushioning. Now the technology has really come a long way.”

The biggest change? The continued ability to make a running shoe lighter, but still give it the support needed to reduce the chance of being injured  especially over a long distance, like a marathon.

Soft and stable

Wilson is a big believer in having good cushioning in a shoe  it cuts down the possibility of injuries.

“That’s why I’ve been able to run for the last 25 years without a lot of serious injuries,” he said. “My knees have been holding up pretty well.”

Every shoe manufacturer has a different cushioning technique.

“The one most people think about is Nike’s air cushioning. It’s actually a form of gas,” Wilson said. “Asics, they use a gel pad for their cushioning. New Balance has a neoprene pad called ‘Abzorb.’ That’s nothing but a neoprene pad they put in the forefoot and the heel. Their claim is that the pad will not wear out.”

Adidas just came out with a shoe with what is supposed to cool your foot as you run, he said. Called ClimaCool, it features vents in the tops of the shoe and on the soles.

I also checked some Web sites for what other manufactures had for cushioning.

Brooks has “HydroFlow” cushioning units, which use a silicon fluid to disperse the shock from the heel strike. Mizuno uses a “Wave” technology using rubber and plastic.

And Saucony uses a “Ground Reaction Inertia Device” or GRID. It uses interwoven Hytrel elastomer put into a gap hollowed out in the heels to provide cushioning and stability.

500-mile limit

Runners should be ready to buy a new pair after about 500 miles. That’s about the time the cushioning starts to wear out. And that’s when you might start feeling the aches and pains in your knees, hips or back, Wilson said.

He provided these guidelines in buying a new pair:

 Make sure there’s a quarter of an inch of space between your longest toe and the front of the shoe. That allows your foot to expand while you’re running.

 The fit in the forefront of the shoe should not be too narrow or too wide.

 The arch of the shoe should match your own natural arch.

 Make sure your heel doesn’t slip around.

Standing in line

“I need some new volleyball shoes. And running shoes,” Bonnie announced at the kitchen table.

With school starting up in a month, there suddenly seemed to be a lot of sports expenses.

Julie confirmed she needed some new shoes for tennis.

I looked at my own shoes again. I could probably squeeze in a few more miles.

I went to look for the shoe glue.