NEW YORK Skiing is a such a skill-based activity that if you don't start learning until you are 20, it will take 20 years to learn.
But fitness experts say proper conditioning can make the difference between a fun weekend on the slopes and one waylaid by injury.
"Skiing first is technique," said Robert Forster, a Los Angeles-based physical therapist and founder of Phase IV Scientific Health and Performance Center. "If your quads (muscles) are just burning up on the runs, then you're not skiing right. That's a good sign that you might need a lesson."
To minimize fatigue and risk of injury, Forster, physical therapist to 42 Olympic medalists, suggests getting in ski-shape before hitting the slopes.
"All fitness begins with an aerobic base," he said. "So six weeks before, start training with an elliptical trainer or stationary bike, or running or walking. Build up to 20 to 30 minutes three times a week."
Aerobic training also strengthens muscles, Forster said, so any subsequent agility drills, such as running sideways or skipping, will be even more effective if you've established an aerobic base.
Stretch before skiing to protect against injury and enhance freedom of motion; stretch afterward to return the muscles to their normal length, said Forster.
He calls stretching the single most important thing people can do for body health maintenance.
"Connective tissue shortens with time," he explained. "We stretch to maintain good alignment of the bones."
If your skiing holiday lasts a week, limit your time on the slopes the first day, Forster suggests. And reconsider that dehydrating après-ski cocktail.
"We know that a glass of wine and a hot tub is not a good idea. Heat adds to inflammation. It will only increase swelling the next day," he said.
Save that soak for the morning, and then not more than five minutes.
Ice down any sore spots or tight areas. "Ice is a great treatment for tightness," he said.
Jessica Matthews, an exercise physiologist with the American Council on Exercise, suggests that even those already in good condition would benefit by integrating sports-specific pre-ski training into their workout.
"Prepare the body to move in short bursts," said Matthews, who notes that skiing demands carving back and forth, rapid turns and sudden changes of direction.
She said it's easy to set up fitness drills using plastic cones, which can be had at any sporting goods store.
"There's great stuff you can do with cones," she said. "Those newer to fitness can begin with stepovers, laterally, side to side. Those more seasoned can make them hops, or invent more intricate drills."
For those who prefer to train in groups, the fitness company Equinox recently launched a class at its clubs called Core Values, which uses low parallel bars, called parallettes, and medicine balls to enhance mobility and stability skills.
"It's geared to help sports people get in condition for their sport," said Lisa Wheeler, who created the class to train across all ranges of motion.
"Even downhill, skiing is about rotation," said Wheeler, an experienced skier. "Most people scoop right and left as they are going downhill."
Falls account for 75 to 85 percent of all skiing injuries, according to the American College of Sports Medicine. Most common is damage to the knee.
Forster said even though more runners than skiers are injured every year, ski injuries tend to be more serious.
"Skiing has much more traumatic injuries that can have long-lasting effects," he explained.
The National Areas Association, the trade association for ski area owners and operators, said U.S. ski areas tallied an estimated 51 million skier and snowboarder visits during the 2011-2012 season.
Forster advises skiers to assess themselves and the slopes before diving down the mountain.
"Is there fresh snow? Heavy, wet snow?" he said. "Be aware of conditions. Fatigue is a big factor. If I had a dollar for every client who got hurt on the last run ..." (Editing by Patricia Reaney and John Wallace)