Cycling outside during the winter season can be a challenge. My toes used to be my weakest link so my "long" rides were limited to the amount of pain I could handle. Consequently getting motivated to ride outside was tough. After an outside ride with frozen toes it would take quite a few days before I could work up the ambition to venture out into the cold once again.
Many years ago I started using the little chemical hand warmers and placing them between my shoes and shoe covers. They work pretty well sometimes. The problem is they need a good air supply to react with the chemicals and my shoe covers were pretty tight. Part way through the ride they would suffocate and I would finish with frozen toes once again. Another issue you run into is trying to wear thicker socks to help combat the cold. This only leads to restricted blood flow to the toes which is just as painful, if not more then cold toes.
As another cold, Iowa winter approached in 2008 I decided enough was enough and I was going to find a different strategy. I had signed up for RAW and knew that I needed to keep my endurance during the off-season and riding indoors was not the way. I started looking into heated insoles or socks. There was not much to choose from Sidi made a very impressive insole but I could not see forking out $300 just for an insole. Besides I was not sure the extra thickness would fit in my cycling shoes. Then I did some serious research on winter riding boats.
Several companies make a winter model of cycling shoe, Pearl Izumi, Sidi and Lake just to name a few. Some road models offer little added warmth while the mountain bike versions are a little thicker. I settled on the Lake's. I ordered one size bigger then I normally wear and got the wide version. Both my road bike and mountain bike have Shimano SPD pedals so I would be able to ride either bike without changing pedals. I also like the BOA retaining system they use instead of laces. This gives an evenly snug fit and allows for easy adjusting even while wearing gloves.
Even with these great boots my toes still get cold when temperatures dip below 40. I have really wimpy toes. During the colder rides I use the chemical hand warmers inside the boots between layers of socks. If you purchase the warmers in 10 packs the cost is about $.80 per ride. This is a small price to pay for comfortable toes.