Expect lots of heavy breathing this weekend

• Several hundred runners will compete in a number of events, including Saturday's Run for Relief, a 5-kilometer race that will feature the reigning NCAA cross country and 10,000-meter champion.

• More than 100 cyclists are competing in the annual Tour of Anchorage, a five-race stage race that began Thursday with a time trial at Kincaid Park.

• Junior tennis champions will be crowned in the Alaska Cup tournament that ends Sunday at the Delaney Park Strip and an American Legion baseball champion will be crowned either Friday or Saturday at Mulcahy Stadium.

And because this is Alaska, many of these weekend warriors will take part in events as extreme as anything happening at this week's X Games in Los Angeles.

Consider:

Today at 3 p.m., a half-dozen runners will leave Hope for a 100-mile race on Resurrection Trail. They'll run through the night -- most will stop at an aid station at the Cooper Landing turnaround only long enough to grab some dry socks or a bowl of soup -- and finish sometime Saturday at the elementary school in Hope.

Another two dozen or so runners will take on the Resurrection Pass 50, a 50-miler from Cooper Landing to Hope that starts at 6 a.m. Saturday.

The race is a low-key, few-frills affair. Runners don't have to pay an entry fee, but then again, race directors don't offer much help along the trail in the Chugach National Forest.

"It's your typical Alaska race -- you're on your own, and you know there's bears on that trail, and porcupines," said Pat Munz, one of the volunteers who helps put on the race. "They're on their own for the first 38 miles (before the first of three aid stations)."

The final six miles of the race feature a one-lane gravel path that rises steadily for 1,300 feet before dropping 200 feet to the finish line in Hope.

Laura McDonough of Anchorage is back to defending her title in the 100-miler, which she won last year in 21 hours, 58 minutes. There's no awards for the winners, but there are rewards for everyone -- Munz and other volunteers supply homemade soup and other treats at the finish line.

Up north, a different kind of extreme race happens Saturday morning near Palmer, where race organizer Lance Kopsack said about 60 runners are expected to test their mettle in the annual Matanuska Peak Challenge. Mat Peak is a quad-crushing, soul-snatching, 14-mile grinder that six-time defending champion Harlow Robinson of Anchorage once described thusly: "On the pain-o-meter, this one goes to 10.''

Runners climb Lazy Mountain, descend its backside, climb Matanuska Peak, descend Mat Peak, climb the backside of Lazy, then, on tortured legs, descend the front of Lazy to the finish line. That amounts to 9,100 feet of vertical climbing and another 9,100 feet of descending.

Depending on the conditions, Mat Peak runners can either flirt with heat exhaustion or hypothermia -- and perhaps both, if the weather turns dramatically.

Runners are responsible for their own water and sustenance. The race was run in such withering heat in 2002 that no less a force of fitness than four-time Olympic skier and race champion Nina Kemppel of Anchorage was reduced to sitting on the ground and picking blueberries to fortify herself. Robinson's fingers became so numb in the rain and cold of the 2007 race that he couldn't get them nimble enough to remove the rain shell around his waist.

Runners can register for Mat Peak beginning at 8 a.m. in the Lazy Mountain parking lot. The pain begins at 9 a.m.

Then there's the Sunday afternoon race in Palmer that sounds extreme but isn't -- the annual Running with the Bulls 5-kilometer race.

There are no bulls but there are musk ox -- the race begins and ends at the Musk Ox Farm at Mile 50.1 of the Old Glenn Highway. And people don't actually run with the musk ox. They run past them, on the opposite side of a fence. The event starts at 4 p.m.

For some runners, Saturday's Run for Relief 5-K in West Anchorage on a course described as fast and flat could offer an extreme challenge: Keeping up with one of the fastest runners in the country.

Sam Chelanga won the NCAA Division I cross country championship last fall and the 10,000-meter track championship this spring for Liberty University, where he is teammates with former Grace Christian runner Ryan Cox of Anchorage.

Cox won the two previous Run for Relief races, "but he's going to have a hard time defending (his title) this time around," race director Scott Clemetson said.

Chelanga will be one of, if not the, fastest distance runners to ever compete in Alaska. He broke his own NCAA 10,000-meter track record in May, clocking 27 minutes, 8.39 seconds. The Kenyan is here to visit Cox and plans to stay long enough to also run in next week's Alaska 10-K Classic, Clemetson said.

About 300 runners are expected for the Run for Relief. The race begins at 10 a.m. at Faith Christian Community Church at 4240 Wisconsin, with registration from 8:30-9:30 a.m. The race is a fundraiser for relief efforts in Burma.

Other choices this weekend for runners include the 5-K Alaska Spirit Run on the Coastal Trail and the Arctic Warrior half-marathon and 5-K at Elmendorf, an event that is part of the Arctic Thunder Airshow.