I’m starting off with a few facts simply to illustrate how complex our anatomy is. Did you know there are 206 bones in our body, and approximately 360 joints and 640 muscles? Our muscles are classified into three types: skeletal muscle- the ones that attach to bones and move us around, visceral muscle, the stuff of our guts and internal organs and cardiac muscle, the heart muscle. Of these three types of muscle, the visceral and cardiac muscle act involuntarily to keep our organism working without us having to think about it which is a good thing.

But our body is not an easily defined thing. We are used to thinking of our body as an assembly of different sections. For example, we may think that the foot is a part of our body on the end of the leg and has no relationship to the hand, the shoulder is a separate area to the knee and they have no bearing on each other. Or deeper: the viscera (your guts) have nothing to do with the spine. We are used to thinking in this way, our western medical philosophy goes right back to the seventeenth century (the philosopher Descartes, look it up!) when anatomists and philosophers began to classify the body into a certain order.

Besides our skeletal system, our muscular system, our cardiovascular system, our digestive, nervous and respiratory systems, and a few others, in more recent times researchers have become aware of another important system in the body - the fascial system. Our bones are coated with a layer of fascia called the periosteum, a membrane which our muscles are attached to, or we could say, our muscles grow from this. Our muscles themselves are contained within a bag of fascia called the perimysium. This forms into tendons at places where the muscle is connected to the bone. Our muscles and bones are communicate with each other via this fascial system. Muscles pull bones into position, bone react to the pull of the muscle, with the ability to increase bone density around the site of continuous pulling. That's the science behind using weight bearing exercise to increase bone mass, really important for us as we age.

These days when I teach movement and fitness to my clients I always talk first about the skeleton and the position of the bones. This is quite different to my days as an aerobics and gym teacher when we talked about muscles, and getting the muscle to bulk up work around the joint. In my experience, just concentrating on working the muscle can lead to imbalances, where one group of muscles becomes stronger than another and pulls the joint area out of alignment. I’ve seen this happen from people doing too many sit ups in the gym for example, when people can develop a round shouldered posture as the too strong abs pull their chest downwards. Think of alignment and postural position and muscles will start to work in their correct sequence.

- Patricia Issitt is a movement therapist and Pilates instructor based in York. Find out more at yorkpilates.com