Sitting down all day can lead to a flat butt because muscles are disengaged for so long that they forget how to wake up.
Officially called gluteal amnesia, doctors have seen a rise in the numbers of people who are desk bound for so long that their behinds essentially falls asleep.
In addition to causing harm to the butt, sitting for long amounts of time can lead to other problems including poor posture, pain in the lower back, hips and knees.
Not working the gluteus maximus frequently can also lead to the muscle losing its tone, meaning a flat and flabby backside.
What is sleeping butt syndrome?
Sleeping butt syndrome was coined by Chris Kolba, a physical therapist at Ohio State Wexner Medical Center, and refers to a combination of tight hip and weak gluteal muscles in the bottom.
Kolba first recognized the problem when one of his clients came in from knee pain while training for a marathon.
Taking a deeper look at the issue, he found that the knee pain was likely caused by the gluteal muscles not functioning as efficiently as they should.
Speaking to the DailyMail.com previously, he said: 'The entire body works as a linked system, and a lot of times when people come in with knee or hip injuries, it's actually because their butt isn't strong enough.
'Sitting for periods throughout the day weakens the glute muscles and puts strain on other parts of our core, as does sleeping in the fetal position.'
Being perched on your bottom for hours at a time will cause muscles to disengage for so long that they fall asleep, even when you aren't sitting down.
Called reciprocal inhibition, the process happens when there's tightness in the hip flexor that creates length in the muscle on the other side and desensitizes it.
After a period of time it won't be able create force or 'wake up' when trying to use it.
Meaning that normal functions of walking and sitting won't see a drastic difference, but when trying to really engage the glutes in exercise, it will take longer to get them into gear.
The bottom should act as support for the entire body and as a shock absorber for stress during exercise but when this fails, it can cause strain elsewhere.
When not used enough, it causes the butt to lose strength which eventually impacts other parts of the lower body.
Testing for sleeping butt syndrome is easy. Squeeze each butt cheek to see if it engages.
How does sitting flatten the butt?
Dan Giordano, a New York-based personal trainer of Bespoke Treatments Physical Therapy, has warned that sitting all day will make your bottom flat, flabby, and saggy.
The lack of blood flow and the slouching position that people generally sit in will do harm to muscle, causing it to slowly waste away.
A startling majority of people, 90 percent, sit the wrong way, with the pelvis shifted forward which puts pressure on the spine.
Giordano said: 'That is going to cause the muscle in your bottom to lose its tone and shape and not be as firm.
'Think about it: if you have a round shaped bottom or a muscly one, and you don't work it out, it becomes flabby and its sags.'
When sitting down for long spells, blood doesn't properly flow through the glutes and the rest of the body.
This will take longer for them to warm up when the time comes to engage them.
How to combat sleeping butt syndrome
Reversing the effects of sleeping butt syndrome and firming up a saggy posterior is possible but will take some effort.
Working all three parts of the muscle is essential - the gluteus minimus, gluteus medius and gluteus maximus.
Specific moves that will target the behind specifically include, donkey kicks, squats, deadlifts, lunges, bridges and planks.
While at work, there are some tricks to keep a flabby butt away.
Walking around, even for 30 seconds to get the blood flowing once an hour, will help firm the bottom back up.
Also try working while standing up. In Scandinavia - ranked as the 'happiest' part of the world by the United Nations - 90 percent of office workers have access to standing work stations.
Studies have shown the act of standing up increases our productivity and dramatically lower the rates of obesity, heart disease and type 2 diabetes.