Runners training for a marathon can get a stress fracture if they. escalate their training too quickly. Stress fractures occur when too much weight or stress is put on a weakened bone. It's often the result of an imbalance in bone health caused by actions that outpace the body's natural bone rebuilding process. See Stress Fracture Risk Factors.
(Intermediate Distribution Frame) A wiring rack located between the MDF (main distribution frame) and the intended end user devices (telephones, routers, PCs, etc.). Cables run from the outside world to the MDF and then to the IDFs. See MDF and wiring rack.
B. Design specifications to consider for the MDF: 1  The MDF is generally located in the basement or bottom floor of a building. IDF's located on the floors above are generally stacked above the MDF to allow for ease of cable distribution and limit cable distances. Cable distance is an important factor for data users. Most data communications systems are limited to 300' maximum, to allow for 100Mbps over 24 AWG twisted pair telephone cable.