This IRB approved clinical study is designed to determine both an effective training regimen to increase GG muscle strength as well as obtain preliminary data on the effect of tongue protrusive force training (TPFT) on OSA. In this study, the investigators will use subjects with moderate to severe OSA. OSA severity will be assessed with a sleep study conducted prior to beginning the training regimen. After six weeks of daily training, OSA severity will be measured again with a follow-up sleep study.