From golf pros to yoga teachers to ski instructors, the people you trust to take you to the next level may actually be hurting you.

"1. You want a lower handicap? You came to the wrong place."
Golfers...start your backswing. The snow on your favorite 18-holer has melted away, and your Bertha's ready for some flexing. But before you hit the fairways, you may need to spend 30 minutes or so getting a tune-up from a nearby instructor. Just beware: Finding a reliable golf teacher could drive you bonkers.

Too often "a guy with a good shtick will get your money," says Wayne DeFrancesco, golf instructor at Woodholme Country Club in Baltimore and one of Golf Magazine's 100 best teachers in the U.S. Maybe that's why the average male golfer's handicap has stayed around 16 the past 10 years -- even though there are now 27,000 PGA-certified golf pros in the U.S. (5,000 more than in 1997). With golfers spending upwards of $200 an hour on coaching, why isn't the overall game getting better? "Bad teaching," says DeFrancesco. He contends that too many coaches aren't even decent golfers. You should hire instructors who have earned a Class A designation from the PGA. That means they've spent around two and a half years training to be a pro and taken 36 hours of continuing education every three years. (To check, call the PGA at 561-624-8400.) Also, ask for their scores in recent tournament play. As DeFrancesco puts it, "If you're a good teacher, you should be able to teach yourself to shoot in the 70s."

"2. I'm no role model for your kids..."
Before a high school wrestling match in December 2002, coach Aron Bright of Avon High School in Avon, Ind., bit the head off a live sparrow in front of his wrestlers. Some motivator, huh? As Bright puts it, "Slightly outrageous is what we were going for." Later, though, when word got out of his stunt, the coach resigned. Bright, who still teaches at the school, says his motivational technique has been branded as "barbaric."

You might say so. And yet, increasingly, coaches are getting reputations for doing more than mouthing off when looking to inspire their young players or intimidate referees. "The attacks (by coaches) are becoming physical instead of verbal," says Bob Still of the National Association of Sports Officials. For instance, in Wisconsin, an assistant coach shoved an umpire to the ground after he was ejected from a youth baseball game in July 2001. Still says, "We get in excess of 100 calls per year reporting physical confrontations; five years ago it was less than half that."

"3...and it's not safe leaving them with me either."
So you think your kid's coach has only Xs and Os on his mind? As you send your kids off for Little League baseball games this spring or swim team practice this summer, be aware that an estimated 15,000 convicted sexual offenders currently coach kids in out-of-school sports, according to Southeastern Security Consultants, a Marietta, Ga., firm specializing in background screenings for youth-league coaches. In Northern California last August, a jury found a youth soccer league commissioner guilty of molesting four boys. On New York's Long Island this past October, another soccer coach was convicted of improperly touching an 11-year-old boy and showing him pornographic movies.

What can you do to keep your child safe from a prurient coach? Be sure your kid's league has done background checks on all coaches and volunteers who come in contact with your children. (Beginning this season, Little League Baseball, the world's largest youth sports organization, will require all local programs to conduct background checks of its coaches.) "People forget that many molesters are affable and charming," says Robert Shoop, author of the upcoming book Sexual Exploitation in Schools: How to Spot It and Stop It. "They seem like the kinds of people parents want their children to be around."

"4. Forget flexibility. Yoga will make you really sore."
Madonna does yoga. So does Cy Young Award-winner Barry Zito. In fact, an estimated 18 million Americans now practice the ancient art with hopes of increasing their balance and strength. Gina Williams, 44, a Columbia, Md., resident, decided to try yoga because she saw it as a gentler form of exercise than the aerobics that she had been doing. But after one strenuous session, Williams wound up with a pulled back muscle and chronic pain that lasted for eight months.

The concern is that injuries among yoga enthusiasts are rising along with the sport's popularity. Dr. Gerard Varlotta, director of sports rehabilitation at the New York University/Rusk Institute in New York City, has seen 50 yoga-related ailments in the past two years, up from 10 in the previous two years. Tom McCook, a yoga instructor with his own studio in Mountain View, Calif., says the spike in injuries can be traced to "instructors having people do things that are high risk and low return." How can a yoga novice avoid a painful introduction? Take it easy. "The instructor should start by teaching you breathing and simple postures -- such as standing correctly," suggests McCook.

"5. Safety doesn't come first when skiing."
Lori McBride, a neurosurgeon at The Children's Hospital in Denver, frequently sees ski accident victims. Fortunately, there have been fewer head traumas in recent years. Why? "Helmets successfully protect the brain," McBride says. "Anybody in ski school should be wearing one." But the Professional Ski Instructors of America takes a somewhat laissez-faire attitude toward the gear. "The organization's opinion is that helmets are a matter of choice," says public relations rep Lisa Winston.

Going without a helmet may have cost five-year-old Leonie Arguetty her life in February 2002, when she was learning to ski in Aspen, Colo. "The instructors took the girl out without a helmet, and one brought her up on an intermediate run. She flew face first into a tree, and her brain was liquefied," says Samuel I. Burstyn, a Miami attorney. He's representing Leonie's parents, Isaac and Miriam, in a lawsuit filed in U.S. District Court in Denver against the ski school, Aspen Skiing Co., charging fraud and wrongful death, among several other complaints. Attorneys for Aspen Skiing Co. were not available to comment on the suit.

"6. You want me to coach you? I can barely jump rope."
Lucy Beale is one of the 2.4 million Americans who have found fitness salvation in Pilates, an isometric-style form of exercise. But while attending a Pilates class two years ago, she noticed the instructor was starting with a position in which you lie on your stomach and raise your arms, legs and head. Echoing a belief that is widely held among seasoned Pilates instructors, Beale, who lives in Sandy, Utah, says, "It was the equivalent of starting a weight-training session by lifting 100 pounds without warming up. It's dangerous." She left in midsession, without paying.

With Pilates participation rising an estimated 40 percent in recent years, there are now more people who want to do the regimen than there are qualified instructors to teach it. "A lot of teachers get certified in a weekend -- and that's not enough training," says Elyssa Rosenberg, a Pilates instructor in New York. She recommends looking for instructors who are Pilates Guild Certified; they will have spent 600 hours apprenticing and taken five written exams.

"7. Take a deep breath before signing our scuba contracts."
Each year 80 or so recreational divers in North America die while in the water. Christopher Murley became such a victim in 1999; he drowned while on his third attempt to see the sunken ship Andrea Doria, located near Long Island. On behalf of Murley's family, attorney Richard Lefkowitz has filed suit against his dive instructor, Joe Jackson, and other related parties in federal court in Central Islip, N.Y.

The suit charges negligence and wrongful death; Lefkowitz contends Murley was too inexperienced to take on the Andrea Doria. Bill Turbeville, attorney for all but one defendant, says that Murley "signed a waiver that releases all parties from any claim of negligence." But Lefkowitz maintains that "instructors use releases to insulate themselves from liability. They need to take responsibility when clients do not meet minimum safety standards."

"8. A package of lessons is a great deal -- for me."
When Mark Pollack signed up for a set of 10 golf lessons at a public course near his home in Hillsdale, N.J., the coach promised to "straighten out" his game. Ten lessons later, says Pollack, "my swing was just as bad as when I started. He offered to give me two free lessons. But I told him that if 10 lessons didn't help, two more would not be the answer."

Coaches of everything from tennis to gymnastics love upfront payments for multiple lessons, expecting a good number of students to lose interest and miss scheduled lessons. A worse occurrence? "Some instructors come in and go through the motions once a week," says Tom Sadzeck, a 13-year tennis instructor in San Rafael, Calif. "Once he has your money, he can lose incentive to do any better than that."

"9. I'm not paying attention."
Sure, if you're a serious athlete, there's something to the "no pain, no gain" mantra. But consider this: A survey by the U.S. Consumer Product Safety Commission found that more than 220,000 children ages 5 to 14 get severely injured annually playing sports. Ouch. Despite these stats, only 12 states require that an athletic department have at least one coach who is trained in CPR and sports first aid. And without that mandate, warns Fred Engh, president of National Alliance for Youth Sports, "some coaches overlook their responsibility" to protect kids from injury.

That's what a jury said in a district court in Pottawattamie County, Iowa, last year. It found the Underwood, Iowa, school district and wrestling coach John Lewis Curtis guilty of negligent supervision for failing to properly care for Nathan Roane, then 16, following a junior varsity wrestling match in 2000. "After Nathan finished wrestling, he got off the mat and could barely stand up," explains Laura Pattermann of Council Bluffs, Iowa, who represented Nathan in the suit. "He was brought into the locker room and left alone on the floor during the varsity matches. He slipped in and out of consciousness and bled internally." But David Woodke, the school district's and Curtis's attorney, contends that "if Mr. Curtis had known the severity of the boy's injury, Mr. Curtis would have stayed with him."

"10. You're gonna hate my practices."
Marcus Pierce, a high school senior in Dodge City, Kan., missed a block during football practice in August 2001. He'll never forget what happened next. According to a lawsuit filed by Pierce, his coach, Mike Schartz, allegedly ran at him and forearmed him in the throat. Shortly thereafter, Pierce complained of breathing problems; he went to the hospital and was placed in intensive care overnight. Pierce's suit, filed in Dodge City's Ford County District Court, charges Schartz with assault and battery and intentional infliction of emotional distress. A spokesman for Clark, Mize & Linville, the law firm representing Schartz, says, "We do not comment on pending litigation, but we do believe our client will be vindicated."

Perhaps, but Tim Flannery, an assistant director of the National Federation of State High School Associations, says too often coaches lack the proper training to communicate with their kids. "Coaches should take a minimum of 40 hours' worth of classes that will teach them to communicate with their players," Flannery suggests. "Tennessee, Washington and Oregon all have programs which require coaches to continually reeducate themselves on coaching students."