Please choose the correct ending to complete the given sentence: Sports and Fitness: [header] How to run long distances in sports [title] Train for the run. [step] Try to run every day or as many days as you can. [title] Stretch beforehand.

Ending1: [step] Time yourself to make up for it. Remember that everything happens for a reason and not just to get in shape. Ending2: [step] You are much more flexible during the run than you would be if you to run all day. [title] Stretch while free weights are being thrown. Ending3: [step] To make sure you're running properly, you need to stretch. Short distances are often more convenient if you are exercising with no blisters on your muscles and no running difficulties. Ending4: [step] Before you run, remember to stretch. Stretching your body is one of the most important things to do in physical exercises.

Answer format: ending1/ending2/ending3/ending4