The elementary physiology of the venous circulation of the lower limbs allows a ready understanding of the favourable effects of muscular exercise and sport in patients with venous insufficiency. However varicose veins may be produced or aggravated by sporting excesses (vicarious varices) or by the choice of certain sports (post-traumatic and post-thrombic varices). In patients with varicose veins and long reflux, sport is more encouraged than in patients with varicose veins and short reflux or patients with post-phlebitic syndrome, except when well adapted bandaging apparatus is used. Sports should be chosen in which the muscular effort is rhythmic and dynamic, while sports in which the effort is static are discouraged. Finally, in order to be useful rather than harmful to patients with venous insufficiency, the practice of sports should be carefully adjusted in amount.