Jared O'Farrell: I've found that while rowing my left leg gets much more fatigued than my right. I've noticed it more in my calf, which becomes very sore and tight, and my hamstring; it is more pronounced after longer sessions. I had knee reconstruction on my right knee two years ago, but it's equally as strong as my left, as I've found from single leg weight training. Is there anyway that I can stop over compensating? Terry O'Neill: There are two possibilities that spring to mind. The first is, as you say, you are over compensating with your left leg. The best way to deal with this is to focus on the three points of contact: feet, seat and hands. Ensure that the load on the feet is the same, the weight on both cheeks on the seat is the same and the load in the hands is the same. The second possibility is a question of circulation in the left leg. It could be that while you were recovering from the reconstruction you overloaded your left leg, and there could be some muscle damage. It doesn't sound serious, but I would get a masseur to have a look at the muscles in the legs to see they are not taut. This would not show up in a strength test as you describe, but would restrict blood flow and cause the problems over a period of time.################################David Ball: I am currently recovering from a lower back injury where I seem to pull a muscle on one side of my back base and crank over probably 30 degrees sideways from upright. It takes about two weeks to recover with the help of Ibuprofen.Doctors say I have a degenerated disc but that is quite common anyway. I have my own Indoor Rower but I don't row a lot, and this injury is not down to recent rowing as I haven't done any, mainly cycling and weights.What I was basically after is advice on the affects of rowing on the back and if there is a way of using it to strengthen the area. If it is likely rowing doesn't help, then I need to consider selling.I would say in the past I have experienced stiffness after a 30 minute row - sometimes I think I 'slump' a bit instead of sitting 'up'.Terry O'Neill: Sorry to hear about your back problems; as a sufferer myself I know how debilitating it is. From what you have said, it seems that the muscle in your back goes into spasm. This is a defence mechanism and is a reaction to another problem, and not necessarily a problem in itself. I would say that cycling is not helping for this reason. The spasm is in one side (asymmetric); cycling is asymmetric while rowing is symmetric. When you get off the rowing machine you say that your back is stiff, but I suspect that it is in the general lower back area not on one side. The question of rowing and back problems is that the lower back is the pivotal point in the rowing action, linking the leg drive and the pull from the upper body. If you train progressively on the rower then the lower back becomes very strong but if you carry a back injury onto the rowing machine it will be exposed. Most rowers who suffer back problems receive the injury from heavy weight lifting. The build for a rower is long levers, while the opposite is required for weight lifting. For this reason, rowers should only train using light, fast, weight programmes that reflect the rowing load and velocity.There are exercises that you can do that will give greater core stability and will benefit you whether you continue to row or not. You can find these in Chapter 7 of the new Training Guide, which is available to download, either in whole or in part, at http://www.therowingcompany.com/training/guide.php