Connective tissue such as your ligaments and tendons takes longer than muscles to adapt to the pressure on your knees when running. So it is important to increase the mileage slowly. [Photo provided to China Daily]

Knee factor

There are often apprehensions that running would hurt knees. This is not without any reason. Connective tissue such as your ligaments and tendons takes longer than muscles to adapt to the pressure on your knees when running.

So it is important to increase the mileage slowly, by no more than 10 percent each week, to give your knees a chance to catch up with the increasing momentum. Runner's knee (the most common injury among runners) is caused if your quads are weak or if you have poor foot mechanics. In such cases, your kneecap will move left and right, and rub against the end of your thighbones, creating pressure, friction and pain under or around the front of your kneecap.

Please refer to the new complete guide to running and four months to a four-hour marathon for more information.