DAMIEN MEYER / AFP/Getty Images

Lance Armstrong crosses the finish line of the 17th stage of the 92nd Giro of Italy on May 27. He finished 12th overall in the three-week race.

It's week three and all is well. I recently read an interview with Lance's teammate, Levi Leipheimer, who said, "He's been away for three years then all of a sudden in the third week of a grand tour you see him start to emerge and start to play in the race." That's about right, and it reminded me of the second comeback in Lance's career.

Everyone remembers Lance's first comeback — the one from cancer — but some people forget that he also quit in the spring of 1998. He dropped out of Paris-Nice, threw his bike in a bag, and flew home to Texas. Somewhere along the way he left me a phone message that simply said he was done, for good. That's why I consider his performances in the fall of 1998 to be his second comeback (making the current one his third, technically).

Following a training camp with Bob Roll and me in and around Boone, North Carolina, Lance trained hard all through the summer in preparation for the Tour of Spain. Yet, despite his commitment to training, he suffered mightily in the first 10 days of the race. Before the 1998 Vuelta, the last Grand Tour he had started was the 1996 Tour de France — and he dropped out on the seventh stage that year. Similar to now, it had been three years since he'd last completed a three-week Grand Tour.

In 1998, Abraham Olano won the Vuelta a Espana, and Lance Armstrong surged from ninth to fourth in the final week. I remember Laurent Jalabert, who finished fifth overall, saying something to the effect of "If the race had been one week longer, Lance would probably have won." Now, I'm not saying the same is true in the 2009 Giro d'Italia, but it's clear that he's adapting to the stress of racing the Giro just like he's always adapted to the stress of three-week stage races.

In terms of the rest of Lance's season, it's not just the adaptation within the Giro that we're looking for. It's nice to see him getting stronger in the third week in Italy, but it's important to also look forward and understand how his performances this week will impact his training and performances for the next few months.

The training stimulus found in the third week of a grand tour is probably the most unique in all of cycling. You simply can't replicate it outside of competing in one of the three biggest races in the world. You have two weeks of high-intensity, high-volume racing in your legs, with one week still to go. If you "cruise" through the final week (as much as that's possible) and then rest afterward, you'll see a reasonable bump in fitness and performance about three weeks after the finish. But, if you're in Lance's position and feeling good, you can ride hard in the final week, take it easy for about a week afterward before returning to a robust training schedule, and then see a really significant boost to your sustainable power output within two to three weeks after the finish.

A big bump from one race gives you the opportunity to start building toward your next goal from a higher platform. You can do intervals at higher power outputs or for longer durations, which in turn lead to further improvements. Depending on the impact the final week of the Giro has on Lance's fitness, he could make a sizable jump in performance within the month of June. Now, back in 1998, there was no other three-week stage race to prepare for after the Vuelta, so Lance focused on World Championships a few weeks later and finished fourth in both the road race and time trial. This year there's the Tour de France.