Frank Mir on natural muscle

Frank MirEd Mulholland/ESPN.com

Incredible bulk: Frank Mir finds himself defending the fact that his weight gain is all natural.

The steroid hysteria in sports -- precipitated in large part by the BALCO scandal of a few years ago -- has resulted in a serious shift in spectator tolerance. Previously, they had little idea how pervasive performance-enhancing compounds were in sports, or that drugs could be used to boost recovery as often as they were sought after for mass.

Now the pendulum is swinging in the opposite direction: Those same fans, burned by their prior assumptions of innocence, have taken to staring accusingly at any athlete who appears to be competing on a suspiciously high level.

The latest toxicology patient is Frank Mir, who seemed to have added 20 pounds of lean muscle in only five months. Mir told ESPN Radio 1100 last week that the 245 pounds he weighed for a July rematch with Brock Lesnar was the result of intense conditioning. Two weeks later, he was 261. The strength training that appeared to pack on 20 pounds between weigh-ins was really responsible for only a few pounds.

Mir is a massive human being to begin with: 5-10 pounds of added mass under the direction of a world-renowned strength coach is hardly alarming. His public trial follows accusations that Georges St. Pierre is part of a lab experiment, Manny Pacquiao's megafight with Floyd Mayweather being dramatized in the media over prefight test protocol and Josh Barnett's third postponement of a California hearing for his positive test over the summer. (The last bit was cause enough for SI.com's Josh Gross to label Barnett the "loser" of the year.)

It's suddenly impossible for genetically and willfully gifted athletes to bolster their physique or output without the shadow of Barry Bonds' overgrown head looming over them. It's still possible to build appreciable amounts of muscle using knowledge, diet and hard work. But it's no longer possible to get the benefit of the doubt.