If you are shopping..

A use bag on wheels, as big, and remember about the rucksack, or bicycle without frame, but for transferring, but not for a sport-tourist loads.
And many doctors in ache advicing to use of exercise bike, this is a mistake, and in different loads will worsen a condition of joint surfaces.Am talking about decompensated exercises,were joints surfaces are instanced, they will not feel a rub, we call theirs as exercises from joint. They are a benefit. Bycicle,walking, swim are in joint, as a joint surfaces moving in contact with each other,after theirs using right away will rise inflammation, and will hurt,edema, and here is a rule, and in kinesis therapy having,as move does not cure! cure is the right move! 
By S.Bubnovski M.D.