Could I be alergic to my 2010 Specialized Vita Comp?

[tzvia]

It's possible. Until recently the only aluminum bikes I owned were full suspension MTBs, ridden in the dirt. For road bikes, it's been Steel and now carbon fiber, till I bought a Fuji road bike to commute with. It has a cf fork, but the rest is alu. Hitting bumps on that bike is jarring. My old steel bikes never felt like that, and the cf stuff is tame by comparison. So I am using 28c touring tires, and am experimenting with finding the best air pressure. I went too low a few weeks ago, and while it felt good, I got a flat. So I went up 10lbs pressure and am being pounded a bit again, but I am getting used to it. I had tried 25c tires, which made the bike feel more nimble (they had higher pressure and a lot less rubber on the casing), but boy every street crack felt like a chasm.

Yea, alu can be more jarring than steel. You might look into wider tires that can be run at lower pressure, if your bike can take something wider than what it has, or check tire pressure as you may be able to lower it a little for a bit more comfort.

[KnottedYet]

Some folks are sensitive to road buzz (not the same as jarring and bumps) from aluminum bikes, and some aren't.

I am, and it is definitely an oddly individual thing. It drove me nuts, yet there are plenty of folks riding aluminum who have no problems at all.

[Aquila]

Is there any chance that you're working harder because you can go faster or something?

Is the soreness improving over, say, a week or two?

[GLC1968]

How often are you riding? If it's only once every couple of weeks, then it might just be general fatigue from the road bike position (and possibly a more jarring ride). I had that problem last summer when I only rode occasionally - each ride wiped me out with aches, pains and heavy fatigue for the rest of the day. This year, I ride more frequently and I don't have the same problem.

I agree with letting a little air out of your tires. If you currently pump them to the max recommended value (like I do), you will probably see a great improvement in road feel if you back them off to the middle or lower end of the rated range for your tires.