Especially if you have not been riding a lot in the past year, a good position on the bike is critical. The most comfortable position on a road bike (NOT the "fastest"...the most comfortable) puts your hands at the same height as the top of the saddle. If the bike is set up correctly, with your hands at the height of the saddle, and your elbows relaxed and bent, your back will be at about a 45 degree angle to a horizontal top bar. Further, your saddle is positioned so that when the pedal is at its lowest point, there is still a distinct and visible bend in your knee.

This position enables you to easily raise up an inch as you go over rough pavement. Having your hands at the same height as the top of the saddle balances your weight between the saddle, pedals, and bars. Keep your hands and elbows as relaxed as possible. Pedal smoothly, at a high cadence, in easy gears, and avoid gears that require "pushing" hard or stressing your knees.

Even with a perfect setup and using easy gears, you will have some aches and pains. Try to ride everyday, even if only for thirty minutes or so. Riding everyday helps your muscles get used to your riding position and after a month of so, your aches and pains will be only a memory.

The typical bike shop employs guys from around age 16 to age 25. They ride with their bars three or four inches lower than the saddle, because it "looks cool". They like to brag about how much pain they can endure on their long Sunday rides. I doubt you are 25, want to "look cool", or want to brag about how much pain you can handle. So, NEVER listen to kids who work at bike shops on issues related to bike setup.