Michael Merzenich, Ph.D. is a pioneer in brain plasticity research and the author of more than 150 peer-reviewed articles. He has received numerous awards and prizes, has nearly 100 patents and has been featured in hundreds of books covering topics such as learning, rehabilitation and plasticity.
There shall not be more than the equivilent of four quarter bends (360 degrees total) between pull points, for example, conduit bodies and boxes. ansi/tia/eia-569-b: 8.8.2.2 Bends
Owing to the durability of rigid metal conduit, you can bury electrical wire in this conduit at a shallower depth. According to the NEC, you can bury it at a depth as shallow as 6 inches. If you wish to use flexible metal conduit, be sure it is the type that is watertight.