Tendon pain from too much use is a very common issue in sports activity. It occurs if the cumulative load on the tendon is higher than what the tendon can take. There is two parts to this: the first is the collective load and that means simply how much exercise is done and just how frequently it is done. It is vital that the tendon has time to adjust to those loads or the collective load could exceed that. Which is the second part, just how adapted the tendon is to those loads. Being familiar with these principles is extremely important in being familiar with and dealing with tendonitis.
As an example, peroneal tendonitis that is an excessive use injury occurring on the outside of the ankle joint. The cumulative load in this tendon is higher when exercise levels are too high or increased too quickly and not enough time is provided for the tendon to adapt to those higher loads. The cumulative load can also be increased by the biomechanics of the feet. For instance, if the supination resistance of the foot is lower then the peroneal muscles on the outside of the lower limb will be required to work harder. That could put an greater strain on the peroneal tendons and then along with training errors that load might exceed what the tendon can take and it develops tendonitis.
Based on these principles, peroneal tendonitis is treated by lessening that collective load. That can mean training amounts and frequency needs to be decreased somewhat to allow the tendon to adapt to the loads. The stress in this disorder may also be decreased with foot orthoses that evert the foot, which means the peroneal muscles does not need to work as hard. Then the tendon really needs to be given an opportunity to get used to the loads. This means that exercising amount and frequency ought to be slowing increased, with lots of rest between training loads to get the tendon to adjust to those stresses.