Tel Aviv, Dec 2 (IANS) Stretching out in front of your TV screen can be promoting ‘active inactivity’, causing you to pack on the pounds, reveals a study.

Such inactivity encourages the body to create new fat in fat cells, said Amit Gefen, researcher in biomedical engineering at the Tel Aviv University.

Gefen along with doctoral student Naama Shoham has shown that preadipocyte cells – a precursor to fat cells – turn into fat cells faster and produce even more fat when subject to prolonged periods of inactivity.

It is the kind of weight we put on our body tissues when we sit or lie down, reported the American Journal of Physiology – Cell Physiology.

The research demonstrates another damaging effect of a sedentary lifestyle.

‘Obesity is more than just an imbalance of calories,’ said Gefen, according to a university statement.

Gefen, who investigates chronic wounds that plague bed-ridden or wheelchair-bound patients, also noted that muscle deterioration is a common side effect of prolonged inactivity.

Studying MRI images of the muscle tissue of patients paralyzed by spinal cord injuries, he observed that, over time, lines of fat cells were invading major muscles in the body.

This spurred an investigation into how mechanical load – the degree of force placed on a particular area occupied by cells – could encourage fat tissues to expand.