If you've got a question for former Olympic rowing coach Terry O'Neill, send it to terry@concept.2co.uk. Peter Lawley: I bought an Indoor Rower about two months ago and really enjoy using it. I began very gently at 25 strokes per minute at about level two or three, then upped it gradually.I started the weight loss programme and after the first session of Anaerobic Threshold work at 3 x 6 minutes and 4 x 6 minutes at around 30spm at resistance seven/eight I sustained severe lower back pain.I thought my technique was OK, moving my back between about 11 & 1 o'clock positions on the recovery and drive strokes, and pulling with my arms at the last minute so I'm not bending forward, but keeping my back straight and head up.What could I be doing wrong, and should I discontinue rowing at all until my back heals?Terry O'Neill: You should stop rowing until your lower back pain settles down. There are two likely reasons for the problem. The first could be tight hamstrings. The second reason could be core stability. The forces created on the rowing machine are divided almost equally between that created by the legs onto the foot stretcher and the force on the handle. The connection is through the lower back and trunk. In the seated position the lower back is almost at the limit of its range of movement and if the muscles of the trunk are relatively weak then you can suffer the problems you describe.The Indoor Rower tends not to cause problems but will expose any muscle imbalance. If you have a sedentary job you will find that the strength in the trunk will decrease at a greater rate than those of the legs. Then, when you row, the trunk muscles do not support the body as they should. The lower back, which through the seated position is already close to its range of movement limit, becomes stressed.When you start any exercise programme it is important to include both stretching for flexibility and core stability exercises both of which you can find on our website at http://www.therowingcompany.com/guide/