The last items looked at seem to stay in the memory longer. For some people music is a study aid. Unlike music, television is a proven distraction. The telephone is an unplanned interruption and, therefore, a distraction. Family or friends interrupting also would be a distraction.
Most people do better at mental tasks when they exercise regularly.
After exercising, it is often easier to relax. When you are relaxed, you concentrate better. Then it is probably time to take a break. If you have developed a schedule that works, it will include timed breaks.