Though running usually improves circulation, there are circumstances when impaired blood flow or nerve conduction cause fingers to become white. Reversible factors, such as exposure to cold or poor ergonomics may be the cause. However, the physical stress of running may trigger an underlying condition, causing fingers to lose blood flow and turn white. If fingers consistently turn white while running, see your health care provider to rule out any potential pathologies.
Cold Effects on Fingers and Hands
If you notice that your fingers turn white while running, first consider the temperature. Running in a cold environment can cause blood vessels to constrict, resulting in decreased circulation to the extremities. A simple solution is to wear gloves or try running indoors. If the color change is not resolved by making this alteration, consult your health care provider. There may be a problem with your nervous or circulatory system.
Postural Effects of Running
Maintaining correct posture while running is important because remaining in a tense position for an extended period of time results in hypertonic muscles, biomechanically impairing circulation and nerve conduction. To prevent this, the body should remain in a relaxed and erect position. The head should be neutral, with the chin neither jutting out nor retracted. Your shoulders should be relaxed and down with your arms swinging freely and hands loosely cupped. An upright position of the back and torso not only allows for better nerve conduction throughout the spinal cord but also allows better respiration. Improved nerve conduction and respiration benefit the circulatory system.
Physical Stress of Running
The ground reaction force exerted by the ground on the runner's body can be harmful. The constant pounding of running causes the low back and extremities to absorb stress three to four times the body weight. Due to the kinetic connection of the upper and lower body, nerves supplying the upper extremities in the spinal cord may be affected. If you have a preexisting ailment such as a herniated disc, you may be more vulnerable to the impact of the ground reaction force. Because nerves supply blood vessels, fingers and hands may turn white due to lack of blood supply.
Running and Circulation
White fingers while running may indicate a circulatory problem. Blood vessels are constricted, limiting blood supply. Fingers may then turn blue due to lack of oxygen, then finally red as hands regain blood flow and return to normal color. People exhibiting this color change are often diagnosed with Raynaud's phenomenon, a condition that causes extremities to turn white. This is often brought on by cold exposure or stress. Because running places physical stress on the body, symptoms may be aggravated.
Raynaud's phenomenon may be either primary, with no underlying pathology or secondary, where it is caused by a disease such as lupus or scleroderma. If the Raynaud's is diagnosed as secondary, the original disease will have to be treated in order to alleviate white fingers.