Trt is testosterone replacement therapy, prescribed by a doctor, usually between 50-200mg/week. Alot of guys will self administer a low dose of test and refer to it as trt as well. Blasting is a part of the blast & cruise style of using gear where someone will run a higher dose cycle for a period of time, usually 8-20 weeks, followed by a low dose or maintenance dose of usually test only at 200-400mg/week for a period of time and then repeat this pattern of blasting and crusing without coming completely off gear. There’s more to it in detail, but that covers the basics. You can find great info using your magnifying glass on the forum with alot of info too. Read through the forum articles there full of good research!