The key exercise for treating proximal hamstring tendinopathy is an eccentric bridge. As you start this type of exercise you should have your feet on the ground with your knees flexed to about ninety degrees. As you get more confident extend you knees so your leg forms a longer lever. As you make more progress you may place your feet on a chair or a swiss ball. It is important to remember that the key component is the lowering phase of the exercise.
The important points to remember are:
Remember these exercises are supposed to be uncomfortable. You should ideally aim for more than 90 repetitions a day. Start slowly and build up to this number. You do not have to do all of the exercises in one sitting. It is more manageable to do a number of smaller sets over the course of a day.