Spending too much time desk bound is causing a new condition dubbed "desk derrière".
Researchers from Tel Aviv University found that the buttocks of inactive people were shrinking and breaking down due to a lack of physical activity, Medical Daily reported.
Scientists scanned several buttocks and found fat calls tended to rise in the rumps of those who led an inactive lifestyle. This led to layers of fat developing deep in the muscle tissue.
"The hip flexor muscles, found at the front of the hip, become over-active and tight if an individual spends all day sitting," physiology expert, Chris Jones, told the Daily Mail.
There are three muscles that give the buttocks its shape - the gluteus maximus, gluteus medius and gluteus minimus. All three become less responsive if you spend too much time sitting, leading to poor muscle tone. The butt muscles are essential to controlling movement in the hips, pelvis and lower back, Jones said.
If you're concerned you might be suffering from 'desk derrière' Jones suggests giving this a try: Lie flat on your tummy, bend one knee to 90 degrees so that the sole of the foot is facing the ceiling. Keep your sole of your feet facing upwards then slowly left the leg about 10cm off the ground by squeezing your bottock on that side. Hold it motionless in the air for 5 seconds. You should be able to hold your leg still. If the lifted leg is shaking or you feel tension in your hamstrings or lower back then your butt muscles aren't in shape.