Air Travelers Should Do Leg Exercises

The United Nations agency said that the risk becomes even higher for tall people, because their legs are pressed in economy class and for the very short people, because their feet do not reach the ground, which causes immobility during travel.

There is a risk category, which includes fat, women, who use birth control pills, and people with blood clotting disorders, as well as frequent travelers and very long journeys takers.

"There is an increased risk of venous thromboembolism during travel where the passenger is seated and immobile over four hours, whether in a plane, train, bus or car," said Catherine Le Gales-Camus, WHO assistant director-general for non-communicable disease and mental health.

"What causes the risk is immobility," she added. "The risk is not only true for people flying."

Thrombosis can be developed if there are no regular muscle contractions that cause blood to stay in the legs and may be the reason for a clot, or thrombus, developed in deep veins.

Thrombosis symptoms include pain or cramps in the calves, and swelling of the leg. However, this disease is very dangerous as it may develop without any symptom and blood clots may reach the lung and block blood flow, which may be fatal.

According to statistics about two billion people take air journeys and even more use overland transport, where they do not move for long periods of time.

Health experts said the overall prevalence of deep vein thrombosis is not so high, noting that the 1 in 6,000 ratio includes those with small or asymptomatic clots.

However, one person is affected in every 20 long-haul flights, if we assume that the plane takes about 300 passengers.

In order to reduce the chance of developing blood clots, WHO special advisor Shanthi Mendis said travelers should exercise their calf muscles with up-and-down movements of the feet and ankle joints, and leave their seats for a few minutes when possible.

Mendis advised air passengers not to take sleeping pills or drink too much alcohol, and avoid wearing tight clothing that can constrain circulation.

"The risk to an individual stepping on a plane is tiny," Patrick Kesteven, a British doctor involved in the 24-page report, told The Associated Press. He added: "The problem is, vast numbers of people step on planes, and so it's a tiny risk multiplied by a huge denominator, so that in terms of a public health issue it's a highly significant problem."

Association spokesman Anthony Council said that many airlines inform passengers of the risk of blood clots. "The advice that we give to passengers is that if you're in one of those at-risk groups you should speak to your physician before traveling."

"For people with high risk, some other factor in aircraft travel may be playing a role," Mendis said, mentioning that still they do not have enough information to determine the reason.

Blood clots can be diagnosed with an ultrasound scan and are treated with drugs for blood thinning in order to prevent their moving to the lungs, heart or brain, which may be fatal.- Alla Harutyunyan for HULIQ.COM