To lift the head or not is often a point of contention in a Pilates class. I remember when I first started doing Pilates I routinely had a very sore neck. And yet, I just kept trying to lift my head up. I thought if I could just figure out how to do it correctly my neck would stop hurting. So I tried and tried and my neck went right on hurting.
Now I know the thing I kept doing wrong was trying to lift my head up when I couldn't recruit the right muscles! I would have been doing myself a much better favor if I had just kept my head down and worked deeply into my muscles, gradually strengthening them so that I would eventually be able to use them efficiently. At the time I was simply unable to stop doing an action that wasn't supporting my workout because I loved the burn from my rectus abdominus when I lifted my head. Without that burn I felt that I wasn't doing enough work and that I was too easy on myself. Since I was taking group classes, I probably looked like I was doing the exercises correctly, even though I was actually in a lot of pain.
My stance on lifting the head currently is this: If you can do it without pain, go for it! This will really work out the front of the body, especially the upper abs and the rectus. If not, work up to lifting your head. Bring it up and down as needed, or use one hand to support the neck. Keeping the head down will work the back body more. You are still working, but the emphasis is different. The most important thing is not to be in a position that is painful, that causes the neck and shoulders to continuously contract and shorten, as this will not get you where you want to be.
Be kind to your body and listen to what it is telling you. Try not to force it to do what it is not ready to do. It will all come with patience, time, and acceptance. Lifting the head when you are unable to support that activity will only reinforce existing muscle imbalances. You absolutely want to feel your muscles being challenged, but that is different from pain. If you are in pain when you exercise you are not doing your body a service.
