The piece of paper taped to Tennessee Titans center Brian Schwenke's locker carried a message that 40 of the more than 1,600 players in the NFL also were supposed to get that week:
"You have randomly been selected by the NFL drug-testing program's Medical Advisor to complete a urine doping test AND HGH blood test today. Please report to the drug testing area immediately to complete the drug test."
So Schwenke broke away from the daily routine at the Titans' headquarters, grabbed an ID and headed to have his blood drawn, just as others around the league have been doing since one month ago Thursday. That's when the NFL instituted a test for human growth hormone — a test experts say is almost impossible to fail.
An Associated Press analysis of the testing protocol approved by the league and the NFL Players Association after more than three years of wrangling found that only the most reckless or uninformed player would seem to have a chance of getting caught using HGH.
HGH has become popular in a variety of sports for its supposed ability to enhance performance in various ways.
Indeed, of the 2,798 HGH tests in sports around the globe analyzed at labs accredited by the World Anti-Doping Agency last year, zero turned up positive.
"You pretty much have to be a fool to test positive at an event or at a (team facility), where there's any possibility of being tested," said Travis Tygart, the CEO of the U.S. Anti-Doping Agency.
Tygart and other leaders of the anti-doping movement say testing alone will not find cheaters — especially because the current test only detects synthetic HGH in a person's system for 48 hours.
Among the deficiencies in the NFL program, critics say:
—Timing and location of the majority of testing is too predictable;
—The selection of who gets tested is actually too random, rather than targeting players who might be thought more likely to be using HGH.
"The players' union invited (USADA and WADA) to be part of the process. When they refused to be transparent, they forfeited their right to be credible critics," NFLPA spokesman George Atallah said.
Asked whether the union is satisfied with the first month of testing, Atallah replied: "Given how new things are, there are always things that can be worked out or need to be improved. But generally, it's working like it's supposed to."
It's far from sufficient, according to USADA's Tygart.
Positive tests are "just highly unlikely, because they've known it's coming and probably stopped well in advance, to have it clear from their system," Tygart said. "The question then becomes: Are athletes going to take a chance?"
One tenet of a strong anti-doping program is no-notice testing, including the idea that an athlete could be tested anytime and anywhere. Cyclist Lance Armstrong, who denied doping for years before admitting it, complained frequently about the numerous visits sample collectors made to his house at all hours of the day.
But the NFL's in-season HGH testing takes place at team facilities, which means players know they only would need to provide a blood sample on days when they're there. Another limitation: Testing is not allowed on game days. During the offseason, a player is given up to 24 hours to set up a meeting, which could allow HGH to leave his system.
"There has to be an unpredictability piece," said Larry Bowers, chief science officer for USADA. "If you look at the WADA code approach, the way they get whereabouts information for the athletes, they try to be unpredictable. It's a very important piece of what we do."
The NFL and the NFLPA initially paved the way for HGH tests in their 2011 labor deal, but it wasn't until this year that the parameters were established: Every week, five randomly selected players on eight randomly selected teams — a computer makes the picks — are told to give blood. There are 950 tests during the preseason, regular season and playoffs combined, 385 more during the offseason.
WADA, though, says HGH testing should increase during what it calls "out-of-competition periods."
One effective part of the NFL program, experts acknowledge, is that players can be tested more than once during a season, which would prevent them from feeling they're "clear" after one test.
NFL spokesman Brian McCarthy noted the rules allow for increased testing if the league finds reason for it, such as a history of violations or a criminal investigation that collects evidence of doping.
"If information is brought to our attention and there is law enforcement activity, then that would be taken into account," McCarthy said.
In 2007, for example, then-Patriots safety Rodney Harrison and then-Cowboys quarterbacks coach Wade Wilson were suspended by the NFL after the Albany (N.Y.) District Attorney's office investigated an Internet drug operation.
Another missing piece in the NFL system, according to USADA, is a lack of state-of-the art "longitudinal" testing, which tracks an athlete's body chemistry over weeks and years.
"We have utilized longitudinal analysis for many years, albeit not in the prospective manner of the more recent 'athlete passport'-type programs," McCarthy said.
In interviews with the AP, players expressed a mix of curiosity, suspicion and nonchalance about the HGH tests.
"I'm definitely someone who doesn't really like needles, but at the same time — and the PA might not be happy with me saying this — I'm all for it, because guys, I'm sure, could get away with it for so long. I want it to be a level playing field," said Washington Redskins linebacker Ryan Kerrigan, who added he was not one of the players selected last month for his team's first go-round of HGH testing.
"I don't know anyone specifically that's on it," Kerrigan said, "but I'd be ignorant to think there aren't guys on it."
AP National Writer Pells reported from Colorado Springs, Colo., and Denver. AP Pro Football Writer Fendrich reported from Ashburn, Va., and Washington. Also contributing: AP Pro Football Writers Teresa M. Walker in Nashville, Tenn., and Dave Campbell in Eden Prairie, Minn., and AP Sports Writer Tom Withers in Berea, Ohio.
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