Yet, for the last month, Dobbs has worn a different brand of energy bracelet on each wrist. “I want to stay impartial,â€? Dobbs said with a chuckle. “Maybe my left side will feel better than my right side.â€?

As Major League Baseball’s postseason opens tomorrow, each contending team is likely to field several players wearing some type of energy-flow bracelet, necklace or apparel.

Sales of the accessories have tripled in the U.S. since 2008, according to research group SportsOneSource. Closely held Phiten Co. said its worldwide sales topped $200 million last year. Bracelets made by Power Balance LLC have been spotted on soccer star David Beckham, Yankees slugger Alex Rodriguez and Hollywood celebrities Robert De Niro and Sean “Diddyâ€? Combs.

The jewelry’s makers say their products use processed titanium and holograms to improve balance, energy, recovery time and flexibility. Critics say the sellers are perpetrating a scam older than professional sports itself.

“This is utter nonsense,â€? said Steven Nissen, head of cardiology at the Cleveland Clinic. “There’s absolutely no scientific reason why this would work. Unfortunately, we’ve not done a good job as a society in keeping people from selling snake oil.â€?

Placebo Effect

Nissen, an advocate for evidence-based medicine who has helped shape U.S. regulations for pharmaceutical companies, said the main reason for the popularity of the jewelry is the medical phenomenon known as the placebo effect.

“If you come in to see me as a patient and tell me that you have a terrible headache, and I give you a placebo sugar pill and tell you that it’s going to relieve your headache, there’s a 35 to 40 percent chance that it will relieve your headache,â€? Nissen said in a telephone interview. “That’s called the placebo effect. It’s very powerful, and that’s what allows quackery to exist.â€?

Erica Jefferson, a spokeswoman for the U.S. Food and Drug Administration, said none of the bracelets have been approved for medical use, and any claims to reduce symptoms or treat a condition must be backed by scientific evidence and reviewed by impartial scientists.

“The agency encourages consumers to report side effects, product defects or health fraud to the FDA — which may include complaints that these products don’t work, Jefferson said.

Shaquille O’Neal

Power Balance, of Laguna Niguel, California, counts among its endorsers 15-time basketball All-Star Shaquille O’Neal and Detroit Lions quarterback Matthew Stafford, the top pick in the 2009 National Football League draft. The company’s corporate partners include Rawlings Sporting Goods, a brand subsidiary of Jarden Corp., based in Rye, New York, and the TaylorMade unit of Adidas AG of Herzogenaurach, Germany.

Power Balance’s wristbands and pendants use a secret hologram technology “designed to interact with your body’s natural energy,â€? said Josh Rodarmel, 26, who co-founded the company with his brother, Troy, 36. Troy discovered the technique of treating holograms with “certain frequenciesâ€? through “trial and error,â€? Rodarmel said.

“As far as studies, we haven’t really commissioned a ton of them because we’ve been using testimonials as our backbone,â€? he said in a telephone interview. “We just let our customers tell the story.â€?

So, has Power Balance commissioned any studies on its holograms?

“No, we haven’t,â€? Rodarmel said. “We are going to probably begin to, but at this point we have not done any studies.â€?

‘Tricking Your Mind’

Nick Swisher, a right fielder for the New York Yankees who wears a Power Balance bracelet and a variety of Phiten apparel, said he doesn’t care if it’s just the placebo effect making him perform better.

“If you are tricking your mind, you’re winning half the battle,â€? Swisher said. “I don’t know if it provides any energy. I don’t need any energy, bro.â€?

Phiten’s titanium products, which range from $25 to $85 for a necklace on the company’s website, are made by dissolving metals and infusing the mix into fabrics. The processed metals “regulate and balance the flow of energy throughout the bodyâ€? and generate “more relaxed muscles leading to less stress and greater range of motion,â€? according to the website.

Phiten, based in Kyoto, Japan, has funded four studies in mice and humans, said Lisa Oka, a spokeswoman.

Improved Joint Range

One completed study of 14 athletes, published in April in the journal Medicine & Science in Sports & Exercise, found soccer and hockey players wearing titanium-treated clothes didn’t play significantly better. Players wearing Phiten garb did show improved joint range of motion, though the texture of the particular garments may be partly responsible for the benefit, the authors wrote.

Phiten is the market leader in sports energy accessories according to SportsOneSource in Charlotte, North Carolina. It has licensing agreements for its titanium products with Major League Baseball, the National Basketball Association and the U.S. PGA Tour. Endorsers include pitchers Josh Beckett of the Boston Red Sox and the Yankees’ Joba Chamberlain, golfer Sergio Garcia and Denver Nuggets forward Carmelo Anthony.

Phiten sells a pure titanium bracelet for $230, as well as titanium-infused athletic tape, lotions and a $170 pillow.

Balance Demonstrations

Demonstrations of balance and flexibility are used to win over leery customers to Power Balance and EFX Performance Inc., another hologram bracelet maker, as well as “As Seen on TVâ€? bracelet seller iRenew Bio Energy Solutions LLC. The performances, which include tests without and then with the jewelry on, may be skewed by administrator bias and muscle memory, the Phillies’ Dobbs said. Still, they’ve made believers of many, including the Philadelphia team’s manager Charlie Manuel.

“I put these on and I noticed the next morning when I woke up, my hands were kind of freeâ€? of chronic arthritis pain, said Manuel, 66, about Power Balance bracelets after taking a balance test. “I’ve been wearing them ever since.â€?

John Murray, a sports psychologist in Palm Beach, Florida, who has worked with professional athletes, said he wouldn’t necessarily advise his clients against wearing the jewelry.

“There’s an old quote, ‘Don’t turn good faith into bad faith,’â€? Murray, 48, said in a telephone interview. “So I’m not going to go around telling people that they’re full of it or they don’t need it if it helps them, but I’m going to promote a more rational approach.â€?

No Scientific Tests

EFX, in Mission Viejo, California, relies on demonstrations to prove its products’ effectiveness, said President Jim Ruschman. The 1-year-old company, whose bracelet is worn by golfer Phil Mickelson, hasn’t conducted any clinical studies.

“We look forward to and embrace testing with anyone,â€? said Ruschman, 52, in a telephone interview, agreeing that the company’s balance tests are unscientific.

A telephone message left for iRenew through its customer service center went unreturned.

Wearing exotic substances to improve health is nothing new; magnets for therapy have been worn for centuries, attracting patients with their unusual properties, according to the U.S. National Center for Complementary and Alternative Medicine in Bethesda, Maryland.

Third-century Greeks wore magnetic rings to treat arthritis. Doctors in the Middle Ages used magnets to treat gout, poisoning and baldness. In the U.S., magnetic hairbrushes, insoles and ointments were widely used in rural areas following the Civil War.

‘Snake Oil’

Studies of magnetic jewelry haven’t shown demonstrable effects on pain, nerve function, cell growth or blood flow, according to the U.S. alternative medicine center.

Power Balance endorser Shane Victorino, a Phillies outfielder, echoed many players’ sentiment when he said: “You’ll never know unless you try it.â€?

“That’s basically what a snake-oil salesman would say in the 1800s,â€? said Bruce Berst, from Casper, Wyoming, who portrays snake oil salesman “Dr. Dumassâ€? in historical re- enactments of life on the frontier. “If you are suffering and can’t find relief, what do you have to lose but a dollar a bottle?â€?

‘Fashion Thing’

Phillies catcher Brian Schneider called energy-flow products a “gimmickâ€? and pitcher Roy Oswalt tabbed it a “fashion thing.â€?

Cole Hamels, the 2008 World Series Most Valuable Player, began wearing an EFX bracelet after taking their balance test in late August. He won his next five starts, the best streak of his career.

“If it’s something that allows me to do something helpful — legally — then I’m all for it,â€? said Hamels, who didn’t know whether the bracelet or his new Phiten socks had helped.

The craze reminds sports psychologist Murray of the film “The Wizard of Oz,â€? when each character sought something symbolic of human success.

“One got a heart, one got a brain,â€? Murray said. “That was all bogus. A guy was behind a curtain. The power, folks, is within us.â€?