It was the obvious question Monday morning for 71-year-old Bill Marshall: Aren’t you still sore?

Marshall, who on Saturday won the national triathlon championship for his 70-to-74 age group, just laughed.

Bill Marshall talks to Shelly Kelley, one of the master's swim coaches, at the Airport Health Club in Santa Rosa in 2010. (PD FILE, 2010)

“It’s why I have a Pilates class today,” Marshall said.

The triathlon course, in Burlington, Vt., was a .9-mile swim, 24.2-mile bike ride and 6.2-mile run, which he finished in two hours, 42 minutes and 18 seconds. It was four minutes better than the runner-up in that age group, which had 26 competitors, including three past national champs.

“I had a very, very good race. I was third out of the water, fourth on the bike and first on the run. I passed people on the run,” Marshall said.

The retired Santa Rosa obstetrician and self-described Type A personality has been competing in Iron Man and triathlon competitions for almost 30 years.

For his age group, Marshall is the current world champion, winning gold last year in Hungary and will compete in three weeks at the world championships in Beijing, China. With the Saturday win, he has a spot on Team USA for the 2012 championships in New Zealand.

As a physician, Marshall sees the benefit of cycling for older athletes. It is easiest to do, kinder on the joints and he thinks better conditioning than swimming.

See photos of Marshall’s training.

Unlike many triathletes, Marshall is fairly good at all three of the triathlon events, but he admits cycling is his weakest because it is where he spends the least time training.

Weak is a matter of perspective. His Vineman 112-mile pace is 20.2 mph.

“Cycling was my best event a few years ago, but it has fallen off, probably because I don’t do as much of it. I only cycle two days a week, but I go race pace, 20- or 30 miles at race pace, 19 to 20 mph.”

Marshall said he usually rides alone, because he feels bad if he drops friends who may be slower, and rides north out of the airport, most often on Eastside, Westside, Pine Flat and Chalk Hill roads.

He’s the one with the gray Kestrel with aerobars, a red helmet, white hair and stops at Jimtown a lot.

You can reach Staff Writer Bob Norberg at 521-5206 or