It is through improved blood circulation that athletes heal from delayed onset muscle syndrome (DOMS). Blood flow improves the health of your strained muscles, reversing the problems created from intense exercising. How Zip-up Hosiery Works Compression hosiery also exists in the form of leg sleeves. The sleeves only cover the ankle and calf region and provide compression on the lower leg region. Leg sleeves or tubes are ideal for strenuous exercising. The sleeves improve circulation on the leg tissues to prevent muscle injury during intense activity. The conditions range from external factors to bodily functions. External factors that affect venous circulation in your legs include gravity and sedentary living (vocations that require sitting for long periods of time). The possibility of blood stagnancy, and the probability of venous insufficiency, increases with these external factors.