I study for around 10 to 11 hours a day and uses table chair most of the time. Now I am feeling pain in my left-hand backside and now I am not even able to sit for more than 4 to 5 hours. I took frequent breaks after every hour of my study, Study by different postures too, but I am still growing in pain. Please advise me. I do some yoga three to 4 times a day to come up with pain, but still not able to get completely fit.