That well-worn phrase "as easy as riding a bike"?

Don't even think of applying it to mountain biking.

Off the road, even the most confident cyclist can go off kilter when learning to handle the sport's ups and downs, ruts and rocks, tricky turns and shifting terrain. It's almost enough to make a person long for the stability and blandness of haulin' asphalt at 20 mph on a road bike without all that shifting, braking and, well, thinking.

Yet there is a challenge, an adrenaline rush to mountain biking that brings many newcomers to the sport. It also brings a lot of business to orthopedic surgeons, who treat broken collarbones and bulging disks after gravity meets ground for inexperienced riders.

The problem for many a novice mountain biker is failure to recognize the technical challenges and intricate skills needed to negotiate a course. That's what led a chastened Jack Paddon of Newcastle to spend a recent Saturday with about 10 other riders honing his mountain-biking skills at an all-day camp run by Total Body Fitness of Rocklin.

Instructor Dan Foster and Total Body Fitness hold instructional camps six times a year (the next is Jan. 30), during which he covers subjects that range from choosing a proper-fitting helmet to executing flawless wheelie drops off a cliff.

"My third time out (on a mountain bike), my buddy got me to the Downieville Classic," Paddon says. "It's 29 miles. I figured, 'Hey, I do 100 miles on a road bike, so I figured it couldn't be that bad. But I got crunched. I finished, but I was so far over my head.

"I'd like to do it next year with some skills."

The mountain-biking camp participants who showed up on a gorgeous fall day at Folsom Lake's Granite Beach ranged in ability from former triathletes who have taken up the sport in recent years, such as Mila Olson of Placerville, to absolute beginners like Jennifer Claausen of Sacramento.

Olson said she has been "getting by" during the mountain-biking segments of adventure races in which she competes, but she needed to learn proper technique in tricky areas like clearing obstacles.

Claausen just wants to stay on the bike without falling and hurting herself. Her motivation? She's married to Clint Claausen, the 2009 men's Category 1 national mountain-bike champion in the 25-29 age group.

"I don't do it much or like it much," Jennifer Claausen says. "I'm normally the pit crew for Clint. But he's like, 'Come on, you gotta ride.' He took me to ride in Mammoth, and I crashed pretty hard. I couldn't walk for three days."

Foster, director of training for Total Body Fitness, has seen his share of spills involving mountain bikers. It's part of the sport, he says – but riders can swiftly improve performance through repetitions of basic techniques.

"It's expected that you're going to encounter terrain you can't handle, even for people with experience," Foster says. "It's not like a road bike, where you get on, ride and then are done. You're going to have to get off and walk a little bit. That's the mountain part in mountain biking.

"The great thing is, all the trails in the greater Sacramento area offer beginner through advanced riding. The faster you ride, the more technical the trails become.

"The main difference between the novice and the advanced rider is cornering. Novice riders can miss a shift or not brake effectively and still be OK. But when they turn wrong, it's over. The novice riders will be left in the dust – or in a bush."

A beginner's guide to mountain biking

Dan Foster, director of training for Total Body Fitness in Rocklin, offered pointers for the mountain-bike novice.

WHAT YOU NEED

Bike: "A first-timer should get a full suspension (shock absorbers on front and back) vs. the 'hard tail' (front shock only). Full suspension is more forgiving. You don't have to have quite the skills if you've got the suspension working for you. You don't want to spend more than $1,000, $1,200. If you spend less than $600, you're going to outgrow (the bike) in one year."

Call The Bee's Sam McManis, (916)