http://www.canada.com/sports/much+fa...145/story.html

Tony Gwynn Jr. summoned his training and experience, but mostly the pedigree bestowed upon him as the son of a Hall of Fame batting champion. Yet, at the moment of truth Sept. 24, staring at Aroldis Chapman's 105-mph fastball, Gwynn did what most of us would do - he froze.

"You're not even going to put the bat on the ball," the San Diego Padres outfielder explained to reporters later, not without trimming away the excesses of a normal hitting sequence. You needed a shorter stride and faster hands, maybe even prayer, because there was nothing normal about Chapman's performance against San Diego that night.

Not only did the Cincinnati Reds' left-hander make history at 105 mph while striking out Gwynn, he broke the century mark on each of his 25 pitches.

Although Chapman owns the crown as the game's hardest thrower, he's just one of several pitchers who've broken through the 100mph barrier. In 2010 alone, there were three other pitchers who did so, including the New York Mets' Bobby Parnell.

Even those who aren't breaking records are getting closer, as more pitchers average in the mid-to high 90s now than a decade ago. And despite the fact that the steroids era is over, reducing home runs by nearly 20 per cent from its heyday, the trend toward better, more explosive fastballs keeps accelerating.

So what gives - is progress really possible without chemicals? Experts believe so. The juicing fraternity has been replaced by a new generation of pitchers who are better trained and better fed, and have a deeper understanding of mechanics than their predecessors.

That's why the 100-mph fastball is bound to become more common, and why, incredibly, Chapman's 105mph heater may yet be surpassed.

"I don't buy into the hard-core statement that the human arm can only handle so much," says California-based pitching guru Tom House, a major league left-hander in the 1970s. "The body will accommodate and adapt to what you ask it to do, if it's done in allowable intervals."

In other words, House says: "I don't think we've reached the maximum yet," likening the 100-mph fastball to the four-minute mile.

"Once it was broken, it was broken incrementally many times after that," he said.

The question is how sustainable these velocities are. Anyone who watched Stephen Strasburg's rise and fall - the incredible buildup, his 14-strikeout major-league debut against the Pittsburgh Pirates and his subsequent season-ending elbow injury - would believe outof-this-world speed carries a steep surcharge.

Parnell admits the idea of hitting 100 mph every pitch, or every game, is a myth. The cumulative trauma can be so great, "Sometimes you pick up the ball and you say: 'Wow, it feels heavy today,' " the right-hander said. "That's when you have to take a day off."

But the threat of blowing out one's arm isn't the deterrent it used to be - not with the evolution of Tommy John surgery. The rehab period keeps getting shorter and shorter, and pitchers with brand new ligaments in their elbows return throwing harder than ever.

Of course, it's not just velocity that makes a pitcher effective. There's a half-serious axiom in the hitters' community that underscores that very point: Even a bullet can be timed, the big boys say, assuming you start your swing early enough. A bullet's trajectory is, after all, straight and predictable, despite its speed.

It's movement, late and unpredictable, that confounds even the best sluggers. Between sinking and cutting the ball, on top of record-setting velocity, the science of pitching never has been more evolved than it is today.

"Guys today do more things with the ball, there's more movement, more action on the ball than I've ever seen," said New York Yankees hitting instructor Kevin Long. "That's why you don't see hitters today with that big leg kick, like (Darryl) Strawberry used to have. There's no time for all the extra movement; hitters have to react so much quicker because the pitching is better."

Long's theory would explain why Babe Ruth was able to use a 48-ounce bat yet never struck out 100 times in any one season. The Bambino also had a massive, time-consuming hitch in his swing, yet was able to catch up to the era's best fastballs. Why? Because historians say Ruth rarely had to deal with anyone throwing 90-plus. Instead, the average fastball of the 1920s and '30s probably was closer to the low 80s.

It wasn't until the '50s that pitchers started to routinely reach the mid-80s. Even by the 1970s, only two to three pitchers on each staff were throwing harder than 90. That's because leg drive was still in its nascent form - although Tom Seaver was a notable exception, dirtying his right knee with his famed drop-and-drive mechanics. For almost everyone else, pitching was all arm, no legs.

The modern-day delivery is borne, in part, by advancements in video technology. Everyone throws harder now because pitching coaches can dissect flaws at 1,000 frames a second.

That's made life tougher on hitters, who see what the future looks like every time the stadium gun readings are flashed on the scoreboard.

"Once you get over 94-95 mph, things start to get uncomfortable for you," said the Boston Red Sox's Carl Crawford. "You see that a lot now, especially late in the game. It feels like every reliever is up there, 98-99 mph. You're thinking: 'Man, that's tough.' "

Crawford won't be happy to hear House's upper-end projection, either. Someone out there is already improving on Chapman's hip rotation, his arm speed and front-to-back shoulder rotation.

The 105-mph fastball isn't the end of baseball's evolution. Instead, it's only the beginning.