With just three weeks to go before the Honolulu Marathon, thousands of runners here and around the world are winding down their training and mulling the eternal marathoner question:

Am I ready?

The answer varies, of course, between conscientious 50-mile-per-week runners ("of course you are!"), late-starting, last-minute entrants ("maybe, but you'll hate yourself in the morning"), and all those who show up on race morning without a lick of training and even less of a clue about what they're in for ("What are you, nuts?").

According to local running guru Brian Clarke, there is at least one universal truth: There is very little you can do in the next three weeks that will make you any faster, stronger or more prepared to run the marathon — there's but oh so much that can trip you up.

"You have to accept your abilities two to three weeks before the race," says Clarke, a former elite runner who has successfully trained hundreds of would-be marathon runners over the years. "A marathon is a marathon. It's 26.2 miles. And you have to respect the distance."

In other words, if you haven't trained as well or as consistently as you would have liked, no amount of cramming will make up the deficit.

Clarke, author of the book "Running by Feeling" teaches his charges to train "in harmony with their energy." That means understanding the messages your body sends.

Whether you go ahead with the race depends largely on whether you are willing to align your expectations with the training and preparation you've already invested — if any.

Completing the standard 26.2-mile race is a tremendous challenge, to be sure, but it is within the capabilities of average recreational athletes who don't mind walking some or most of the course — likely for eight to 12 hours.

"It comes down to how fast you want to do it," Clarke says. "Every year, there are a lot of runners from Japan who have not run or even walked a step in training, and they'll do it. They won't enjoy the second half of the race and they won't feel good the next day, but they'll do it."

Even well-trained athletes find themselves sitting on the fence in the weeks leading up to the big race, wondering if they've trained enough to accomplish whatever goal they've set for themselves.

Al Vincente, 42, of Pearl City, has completed 11 marathons. Before each one, he says, he seriously entertained thoughts of not showing up.

"When it's your first time, you wonder if you can really do it," he says. "After that, you wonder if you can make the time you want to make, or if it'll be worth the effort, or if you're going to suck eggs because you didn't train right."

Clarke says a little uncertainty is common, especially this year.

"More so than in other years, a lot of people haven't made up their mind to do it," Clarke says. "Some come into the training late. Some have doubts about their ability. And yet some of those with the biggest doubts also have the biggest ability."

Heather Knox, 38, of Nu'uanu, is an experienced marathon runner, but she wasn't sure she could go through with this year's race after injuring a hamstring muscle early in her training.

With Clarke's careful oversight and a rigorous regimen of spinning, weight training, stretching and yoga, Knox maintained her fitness as her injury slowly healed. But then she suffered a setback after the Niketown 30K race last month.

"I felt like my injury was back at the beginning and I lost a little bit of motivation," Knox says. "It was really discouraging that I tried to do the right things, but I kept getting setbacks."

Following Clarke's advice, Knox has resisted the urge to push through her training. By running moderate distances and maintaining her cross-training regimen, she's allowing her body to strengthen and recuperate, giving her the best chance to run a comfortable and satisfying race on Dec. 10.

"I'll have to pace myself so I'll have the stamina to complete the race and feel strong," she says.

Twenty-four-year-old Natalie Sutherland of 'Ewa also had her marathon training interrupted by injury. First it was a painful "snapping" hip that required a month of physical therapy. When that was under control, the iliotibial band in her left knee flared up.

"I was so mad," she says. "I was feeling good. I felt mentally prepared. It was hard to take."

But take it she did, along with a heaping helping of "just be patient."

Three Sundays from now, Sutherland will line up for her first marathon with more than 22,000 other runners who found their way off the fence. If the pain isn't too bad, she'll find out exactly what she's capable of. If things don't go as well, she'll take the lessons she's learned from her training and deal with it.

"I know how to pace myself," she says. "If I'm hurting, the best thing to do will be to stop, walk and just enjoy the race.

"I've always wanted to complete a marathon," she says. "I feel great."

Says Clarke, "All you can do at this point is accept your abilities. Next time you can train earlier or better. Once you accept your ability, it's not that big a deal."

Primed or not

Reach Michael Tsai at mtsai@honoluluadvertiser.com.