Simultaneously, the internal diameters of veins and venules narrow in a process called venoconstriction, forcing the flow of blood forward to the heart and enhancing their ability to receive blood coming from the capillaries. Overall, this process helps decrease the pressure in the venules and veins to at most about five mmHg. Venous volume and pressure thereby decrease and are thus not the basis for the bulging.
Instead, the process occurring in the capillaries as a result of the rise in arterial blood pressure during exercise causes plasma fluid otherwise resting in these tiny tributaries to be forced out through the thin vessel walls and into compartments surrounding the muscles. This process, known as filtration, causes a swelling and hardening of the muscle that is noticed during exercise.
As a result of this swelling, cutaneous veins are pushed toward the skin surface, flatten to some extent, and appear to bulge. Such veins are more visible in persons with less subcutaneous fat. This bulging is neither good nor bad but simply a result of normal physiological mechanisms that result from the rise in arterial blood pressure during exertion. Already a subscriber? Sign in. Thanks for reading Scientific American. Create your free account or Sign in to continue.
See Subscription Options. Go Paperless with Digital. However, anyone with health concerns should speak to a doctor to make sure that they are not the result of an underlying condition. Keep reading for information on what causes hand veins to bulge and the possible treatment options to get rid of them. Fat on the hands typically helps make veins less visible. People who are underweight overall or have thin hands may find that their veins are more prominent.
When it is hot outside, the body sends extra blood to the surface veins to try to cool the body. Sometimes, this can affect how well the veins work.
If this occurs, they may enlarge as more blood pools in the hands. In most situations, the veins return to normal once a person has finished exercising. However, if a person exercises frequently, their veins can start to bulge permanently in their hands and other areas of the body. This effect is particularly likely to affect those who frequently lift heavy weights. People with an immediate family member who has bulging hand veins may be more likely to have prominent veins in this part of the body.
Phlebitis is inflammation of the veins. It usually has an association with another condition, such as an infection, autoimmune disorder, or injury. Varicose veins are more common in the legs, but they can occur in the hands as well. Varicose veins form as a result of the valves in these vessels not functioning properly.
Varicose veins make proper blood flow more difficult. The condition can cause gnarled, enlarged, and possibly painful veins. Superficial thrombophlebitis is the swelling of a vein that is close to the surface of the skin. A blood clot is often the underlying cause.
A clot may develop following the prolonged use of an intravenous IV drip or other trauma to the vein. Superficial thrombophlebitis can be painful or uncomfortable, but it is not usually dangerous. Deep vein thrombosis DVT is similar to superficial thrombophlebitis. However, in DVT, the blood clot occurs in a vein that is deeper in the arm.
In people with DVT, there is a risk that the clot could break loose and make its way to the lungs, which could cause a pulmonary embolism. Bulging veins and veins popping out are common among both men and women of all ages.
Read through this blog article to learn more about vein health , and learn if your bulging veins are healthy, or actually troublesome. A malfunctioning valve in the veins causes them to project outward, or bulge.
You may notice your vein bulging with a lack of movement after sitting for an extended period of time. Bulging veins can also occur with aging, obesity, and pregnancy.
Valves are like one-way flaps that help to regulate blood flow through the veins. Instead, blood flows backward which leads to veins becoming enlarged. In many cases, vein bulging is normal to see in certain situations. You can expect veins to naturally bulge under the following circumstances:. Varicose veins are particularly common among pregnant women. Although the vein bulging can be discomforting and bothersome, it is not life-threatening.
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