He's working out once in the morning and the afternoon and only recently started throwing a baseball, so he'll get a better idea how his back responds during Spring Training.
"I'm doing all the exercises they showed me to do as far as strengthening the lower back and doing a little bit less long cardio and a little more short stuff, like quick bursts here and there," Oswalt said. "Instead of running three or four miles, I'm trying to do a little more accelerating stuff."
Oswalt, 32, went 8-6 with a 4.12 ERA last year and set a franchise record with 16 no-decisions before finishing the year on the disabled list. Oswalt has been diagnosed with a bulging disk that causes hip pain and has caused numbness in his hand.
"I think people read into it a little too much it," Oswalt said. "I'll be ready when it gets time to go. This new workout stuff should help a lot."
Oswalt, who joined teammates Geoff Blum and Pedro Feliz and Astros legend Craig Biggio on the Astros' Winter Caravan tour Wednesday with stops in Galveston County and NASA, said he quickly lost 12 pounds on the new workout routine.
"I feel like I'm getting in shape quicker this way," Oswalt said. "I just started throwing this week. I've been lifting [weights] for couple of months now, and it seems like it's coming together well."
In some ways, there's a case that last season was an aberration for Oswalt.
Not only did he post career-lows in wins and ERA, he pitched two games in the World Baseball Classic in March -- and made three more appearances in exhibitions -- and already had a few innings under his belt when he reached Opening Day.
"I only missed three starts and started five in the WBC, so that's 35 starts," Oswalt said. "I think I'll be in good shape. [The back problem] is not in the back of my head or anything like that. If I have to, I can pitch through it and hopefully for the entire season I'll be pain-free."
While spending his offseason in rural Mississippi and helping the day-to-day operations with his restaurant he opened in November, Oswalt kept an eye on the Astros. He liked the addition of Brett Myers to strengthen the rotation.
"I think we're going to be OK if Myers comes in and pitches good and Wandy [Rodriguez] pitches the way he did last year," Oswalt said. "The biggest thing is health. Most teams you see in the World Series, they stay healthy the whole year. That's the biggest key in the big leagues. The talent is there, but we have to put it all together and stay healthy. Adding a new manager and a pitching coach is a help for us."
Oswalt has liked what he's heard so far from new manager Brad Mills and is excited about working with new pitching coach Brad Arnsberg, who spent the previous five seasons with the Blue Jays and is a veteran of six Major League seasons as a player. Arnsberg got a ringing endorsement from former Astros pitching coach and current Rays pitching coach Jim Hickey.
"I think it's going to work out well," Oswalt said. "He fits our club well. We have some guys on the team that have the same background as he does. A lot of people from the side don't know what it's like to get on the field. Being out there, he can understand how hard the game is, and you learn a lot from guys who had trouble getting through the season when they're hurting."