Sclerotherapy is a widely used, minimally invasive treatment for addressing both varicose and spider veins. The procedure involves injecting a specialized solution directly into the affected vessels to cause their closure and eventual disappearance. Following this treatment, medical professionals mandate temporary restrictions on exercise and strenuous activity because the initial healing process is delicate and can be easily disrupted. Understanding the mechanism by which the veins close provides the necessary context for these temporary limitations.
How Sclerotherapy Works to Close Veins
Sclerotherapy relies on a chemical irritant, known as a sclerosant, to seal off the targeted vein. The solution is injected to intentionally damage the delicate inner lining of the vein wall (the endothelium). This injury triggers a localized inflammatory response within the vessel.
This controlled inflammation causes the vein walls to swell, become sticky, and ultimately collapse inward on themselves. The body’s natural healing process then takes over, leading to the formation of a thrombus, or clot, inside the collapsed vein. This clot acts as a biological seal, permanently blocking blood flow through the vessel.
Over weeks to months, the body gradually replaces the clotted vein with scar tissue through fibrosis. The sealed vessel is then naturally reabsorbed, causing the visible vein to fade. For the treatment to be successful, the initial thrombus must remain stable and intact long enough for permanent sealing to occur.
Why Increased Circulation Undermines Treatment
Strenuous exercise directly threatens the stability of the newly formed thrombus. Physical activities that significantly raise the heart rate (running, high-impact aerobics, or heavy weightlifting) cause a rapid increase in systemic blood pressure and blood flow velocity. This surge of blood exerts mechanical force against the walls of the treated veins. The increased pressure and volume can physically dislodge the immature clot before it has had a chance to firmly adhere and seal the vein wall.
If the clot is washed out or partially broken up, the vein may reopen, allowing blood to flow back in and causing the treated vein to fail. This results in the recurrence of the vein, known as recanalization.
Vigorous activity can also cause the rapid washout of the sclerosant agent from the injection site before it has finished its chemical ablation of the vein lining. This premature dilution reduces the solution’s effectiveness, potentially leading to an incomplete closure of the vessel. Furthermore, the elevated pressure can contribute to increased localized swelling, bruising, and pain in the treatment area.
Safe Movement and Return to Exercise
While intense activity is restricted, immediate gentle movement is a necessary part of the recovery process. Patients are typically instructed to take a 30 to 60-minute walk immediately after the procedure. This light activity helps promote healthy circulation in the surrounding, untreated veins, which is important for preventing the formation of deep vein thrombosis (DVT) in the leg.
For the first two weeks, the focus should be on low-impact walking, avoiding activities that involve straining, pounding, or heavy impact. Restricted activities include running, jumping, high-impact sports, and lifting heavy objects, as these significantly increase abdominal and leg pressure. Moderate exercise, such as cycling or swimming, can typically be resumed around two weeks, while a return to strenuous activity is generally advised after four to six weeks.
The use of medical-grade compression stockings is mandated to mitigate the risks associated with increased circulation. The stockings apply consistent external pressure, which helps keep the treated veins collapsed and flat, physically supporting the integrity of the forming clot. Wearing these garments, often for seven to fourteen days, aids the healing process and is required for optimal treatment outcome.