Mounting an aggressive campaign against a report that linked him to performance-enhancing drugs, Peyton Manning, the Denver Broncos quarterback, said Saturday night that he was treated at an anti-aging clinic in Indianapolis in 2011 while recovering from a neck injury but that the treatment was prescribed by his physician and did not involve any banned substances.
A report by Al Jazeera, published online early Sunday and scheduled to be broadcast on its TV networks later in the day, contends that some of the biggest stars in Major League Baseball and the National Football League are taking a host of designer steroids and other banned performance-enhancing drugs. Among those implicated in the investigation, which used an undercover reporter with hidden cameras, was Manning, one of the best quarterbacks in the sport’s history. He has never previously been linked to doping.
Men described as doctors, pharmacists, naturopathic practitioners and other specialists told Al Jazeera’s undercover reporter that they frequently and routinely dispensed drugs to pro baseball and football stars.
One specialist, Charles Sly, whom Al Jazeera called a doctor of pharmacy, claimed that the anti-aging clinic in Indianapolis where he worked in 2011 sent many shipments of human growth hormone to Manning’s wife, Ashley. He later told Al Jazeera that he was not truthful in talking with the undercover reporter.
In a statement, Manning called the allegations “complete garbage” and “totally made up.”
“It never happened,” Manning said. “Never. I really can’t believe somebody would put something like this on the air. Whoever said this is making stuff up.”
A spokesman for Manning disputed that Sly worked at the Guyer Institute in Indianapolis when Manning sought treatment there, as Sly implied in the documentary. Sly was an unpaid intern at the institute from February to May 2013, not in late 2011, when Manning went there, the spokesman said.
Manning’s agent told Al Jazeera that any medical treatment Ashley Manning received was private.
The N.F.L. declined to comment on the report. The league did not test for human growth hormone until 2014.
In a letter he sent to Al Jazeera, Sly said the statements he made on camera were “absolutely false and incorrect.” He said that the undercover reporter, Liam Collins, badgered him to talk while he was grieving the loss of his fiancée, who had recently committed suicide. As a result, Sly was in “no state of mind to be making any coherent statements,” he said, and Collins “clearly was taking advantage of my grief.”
Every other player named in the report either denied the allegations to Al Jazeera or did not respond.
In the hourlong documentary, “The Dark Side: Secrets of the Sports Dopers,” Collins, once a top British hurdler, posed as an athlete in search of performance-enhancing drugs to fuel his return to the upper ranks of his sport.
Though Major League Baseball and the N.F.L. have strengthened their antidoping programs in recent years — adding, for instance, blood tests for human growth hormone — the documentary shows how those protocols remain full of holes that players can easily exploit.
Collins traveled to Austin, Tex.; Vancouver, British Columbia; and beyond to meet men who provided him with a host of drugs and instructions on how to use them to regain his vigor on the track.
In the documentary, the men tell Collins, who tapes their conversations surreptitiously, how quickly these drugs will increase his strength and performance, and they brag about how easy it is to avoid detection.
“Have I doped people? Oh, yeah,” Chad Robertson, a Canadian pharmacist, tells Collins. “And no one’s got caught because the system’s so easy to beat. And it still is; that’s the sad fact. I can take a guy with average genetics, and I can make him a world champion.”
Robertson and his partners in Canada — along with pharmacists and doctors in the Bahamas, Texas and elsewhere — tell Collins they can provide him with the blood booster EPO, insulin, testosterone and Delta-2, or Androst-2-en-17-one, a banned performance-enhancing drug that they claim is widely used by pro players.
Sly met with Collins in Texas. Sly said the Delta-2 would increase his strength by 10 to 15 percent in about a week. He also said he could provide Collins with peptides to increase his energy and drugs designed to combat fatigue and increase libido.
In one scene, Collins talked with Sly and Taylor Teagarden, a catcher from Texas who played parts of the past eight seasons with the Rangers, the Orioles, the Mets and the Cubs. Teagarden, who is shown sitting in Sly’s apartment, said that he used Delta-2 and peptides and was not caught.
Sly also said he provided Delta-2 to Philadelphia Phillies first baseman Ryan Howard, Washington Nationals first baseman Ryan Zimmerman, and Pittsburgh Steelers linebacker James Harrison. According to Al Jazeera, each player “emphatically denies” taking the drugs. Sly said he spent six weeks in Green Bay dispensing drugs to Mike Neal, a Packers linebacker, and teammates including Clay Matthews and Julius Peppers.
The Packers, Neal, Matthews and Peppers did not respond to requests for comment by Al Jazeera. The Packers did not respond to a request for comment by The New York Times.
Peppers in 2002 and Neal in 2012 were suspended for steroid use for four games each, according to N.F.L records.
Robertson and Brandon Spletzer, a naturopath also in Vancouver who dispensed drugs to Collins, did not respond to inquiries from Al Jazeera for subsequent comment.
Interviewed by Al Jazeera, Eddie Dominguez, a former Major League Baseball investigator, estimated that 20 percent of professional players were still taking performance-enhancing drugs, and he said M.L.B. made too much money to want to stamp out their use.
“Like any corporation, it’s there to make money, and all we were doing was adding bad press to Major League Baseball,” he told Al Jazeera.
An M.L.B. spokesman said Dominguez was a disgruntled former employee who was terminated with cause about two years ago. The spokesman called Dominguez’s comments “patently untrue.”
Al Jazeera paid Collins, 37, for his work on the documentary. Using the network’s money, Collins paid about $500 for drugs in Canada, though he did not take them. He also paid for a blood test and bought Sly a $250 gift card to Whole Foods.
Collins had a career best of 50.30 seconds in the 400-meter hurdles, in 2002. He missed making the British Olympic team and retired in 2006 but has since returned to competing in Masters division races.
In 2009, he appeared on the television show “Britain’s Got Talent,” in a dance act. He and a cousin, David Bone, then reportedly collected hundreds of thousands of dollars from investors seeking high returns in a venture that would buy and renovate homes. The business later collapsed.
Broke, Collins became a street performer, he said in an email on Saturday. He then contacted the American sprinter Tim Montgomery, a former world-record holder in the 100-meter dash who was banned for taking steroids, to work on a biography of the disgraced runner. Through Montgomery, Collins was contacted by Al Jazeera to work undercover.
Collins said he was surprised by “the sophistication of it all,” including a 65-page protocol written by one specialist that included several banned substances and as many as 10 injections a day. Collins was also offered drugs that were not approved for human consumption, he said.
Collins said none of the doctors or pharmacists he met showed him documentation to support their claims that they supplied performance-enhancing drugs to pro athletes.
“This isn’t a world where detailed documentation is often kept,” Collins said. “It rarely, if ever, goes beyond the athlete and the doctor/pharmacist. There’s no incentive for either of them to talk or to write anything down.”