Go ahead, test my blood! It's the only way we'll stop the cheaters.

Concussions. The 18-game season. A potential lockout. They're all hot-button topics in the NFL. But in my eyes, none of them compares to the issue of pros using human growth hormone.

A few seasons ago, strength coaches I know began whispering about players they were convinced were using HGH. I was surprised by the names, as most of the guys' bodies weren't all that huge. They told me to ignore size and look for guys who were transforming their bodies unreasonably fast. So I started paying closer attention. And guess what? I could tell.

Unlike steroids, HGH doesn't help you build muscle mass so much as make you leaner and help you recover from injury quicker. I began to notice guys who'd been soft and pudgy for years showing up at training camp 20 pounds lighter and looking ripped. And then there were guys who usually ached all year long -- they had gimpy knees or bad shoulders -- who weren't showing any pain.

I also noticed that players entering the last year of their contracts were suddenly in the best shape of their lives. Guys will try almost anything to be in shape in a contract year, and for good reason. Unless you're a high draft pick, you're probably playing on a rookie deal that undervalues you. Ditto older players, who figure the reward is worth the risk. Former Patriots safety Rodney Harrison, who got pinched for HGH in 2007, is a prime example. An aging vet like him thinks, Maybe this stuff will help me squeak out two more seasons at three mil a year. Can you really blame a player for trying to get his while he still can?

Players I know see HGH as having very little risk. Detection is hard, since it requires a blood test, which our union opposes. The only way a player can really get busted is if he gets sloppy and discloses his real name and address to his supplier, as Harrison did. And, worst-case scenario, a four-game suspension without pay is hardly a deterrent when we're talking big-time money. Also, there's not as much stigma in the NFL if you get caught. It's not like baseball, where a guy like Roger Clemens will likely go down as a cheater. In football, you serve your suspension and everybody moves on. It's a violent sport, so I think a lot of people are quick to forgive if they find out we take something to help us with injuries and strength.

HGH has spread fast around the NFL because players from different teams train together during the off-season. They hear about it, try it, then take it home and tell their teammates. I'd say about 20 percent of the guys in my locker room are on it, and that's relatively low. I've heard of teams where it's closer to half the roster. I bet an average of four out of every 10 NFL players use HGH.

Crazy thing is, coaches pretend it's not happening. In the NFL, all they care about is production. Coaches just want plausible deniability. I guess part of the reason they can sleep at night is that HGH's side effects don't seem to be all that negative. Even doctors don't seem to take them quite as seriously as they do steroids.

None of that matters to me. HGH is still a performance-enhancing substance, and that means it's cheating. It would tarnish what I've accomplished in the NFL, not to mention what I've done my whole life, if I took it. Maybe I'll feel differently when I'm near the end of my career. For now, even though I have to compete against guys who have an unfair advantage, I feel like I can rise above with good, old-fashioned hard work.

But I do wish they'd test our blood. I'd give it every day! It's amazing they don't test for HGH given how passionate they are about curtailing all other PEDs. I've had seasons when I've been randomly tested 10 times. Before the offseason, you have to write down all your planned trips, with dates and locations. They have people everywhere, so they'll find you. And yet they can't probe for this stuff.

But the last thing the NFL wants is a black eye from any potential fallout, so I think it's only a matter of time before they start testing our blood. When the new collective bargaining agreement comes up at the end of the season, I wouldn't be surprised to see the league push for HGH testing. Until then, a lot of players will keep doing it.