Well i dont know abou tthe international rules (dont care really) but APA, APF, WABDL, WPO, IPA, your allowed to lift your head. Your shoulders and butt must stay in contact. Tell me though, how can you bench if your shoulders dont touch? USAPL not sure but hell they dont even have a press count so in doesnt matter anyway. So lift that head! Or the bar will not come down in denim. At least not as well.