Instead of his wife not being able to keep up, a more probable scenario would be that Lance couldn’t get it up. I realize that this sounds crude and insensitive, but Armstrong did have testicular cancer and although we know he has been cured, we do not know what type of treatment was used or how extreme this treatment may have been. Couple that with an increased rate of erectile dysfunction among bicyclists that practice extreme training (Erectile Dysfunction and Bicycling)and this does seem probable. It also goes a long way in explaining his remarks, "We're closer now and better friends than ever before," and, ""We're truly committed to maintaining a good relationship, but not a marriage" since some marital obligations could no longer be preformed.