When it comes to running, Chuck Brockman is a creature of habit.

He’s become accustomed to the gradual downhill of the Soda Creek Trail as he winds back from Green Lakes, a roughly 13-mile loop in the Three Sisters Wilderness. But on a run that long, even Brockman — a physical therapist and director of Therapeutic Associates’ Bend clinic — starts to feel it in his joints.

“When I wear the Hokas, I don’t nearly feel it as much,” he said.

For the past two years, Brockman’s longer runs have been in Hokas, a popular style of maximal shoes, those known for the thick layer of cushioning along the bottom. Runners like Brockman who’ve come to prefer maximal shoes said they do so because they seem to make longer runs hurt less, especially at the 10- or 12-mile marks, when the hip and knees take a beating.

The common wisdom has been that’s because the shoes’ extra cushioning absorbs some of the shock of the feet hitting the ground. The more shock — referred to by those in the know as ground reaction force — that occurs, the higher the likelihood a runner will sustain an injury, most likely in the form of a stress fracture, plantar fasciitis or achilles tendonitis.

After hearing from more and more runners like Brockman, Christine Pollard, director of the Functional Orthopedic Research Center of Excellence Lab in Bend, decided she wanted to test that assumption once and for all. Her team launched a study last summer that tested, among other things, whether runners’ ground reaction forces were lower in maximal shoes compared with typical running shoes.

Their answer came as a surprise: They weren’t. Runners’ feet struck the ground with virtually the same force regardless of the type of shoe they wore.

“I think everybody just assumed, ‘When there is more cushion, it’s going to help distribute that force differently,’” said Cindy Conti, manager of the FORCE Lab, which is a partnership between Oregon State University-Cascades, The Center Orthopedic & Neurosurgical Care & Research and Therapeutic Associates’ Bend clinic.

The study was small — it included 18 females and eight males between the ages of 18 and 45 — and it has not yet been published in a scientific journal, although it was presented last month at Northwest American College of Sports Medicine’s annual conference. New Balance, which makes it own styles of maximal shoes, provided funding for the study.

In addition to strike force, researchers also measured how much subjects’ knees and hips bent while running and the angles at which their feet hit the ground.

The study noted a very subtle increase in how much runners bent their knees and hips in maximal shoes: 1.6 percent more in their hips and 1.3 percent more in their knees. Pollard said that can be a good thing, because it means people are making better use of their internal structures to absorb the force during running.

Brockman said he doesn’t think there is enough research on maximal shoes to determine whether they make runners less prone to injuries. In fact, despite advances in footwear technology since the 1970s, he said injury rates among runners are largely unchanged.

For him, the bigger issue when it comes to choosing a running shoe is whether it feels good.

“I’m a big proponent of running in shoes that are comfortable,” he said, adding the exception that he recommends shoes with more support for clients’ whose feet tilt inward severely when they run.

Despite there being more distance between the ground and his feet in maximal shoes, Brockman said they don’t make him more prone to tripping while running. His wife, however, feels she is.

“She does not like not feeling that ground underneath her foot,” he said. “It makes her feel a little funny.”

As with the switch to any new running shoe, Brockman said there will be a transition period before people feel comfortable in maximal shoes.

Pollard’s team is repeating the study this summer. But this time, they’ll ask subjects to take a “fatiguing run” rather than the short bursts of running they did for the previous one. The idea is to learn whether maximal shoes reduce ground reaction forces over a longer period of time, especially after runners begin to get tired. (Fatiguing runs can be measured using a number of different protocols; Pollard said she’s not sure yet which they’ll use.)

— Reporter: 541-383-0304,

tbannow@bendbulletin.com