We talk a lot on our Fresh Steps course about the enhanced value of exercise as we grow older. We know that we start losing muscle as we get over 30 and that regular training with weights can help to offset this. One of the benefits of building muscle is that it is a metabolically active tissue. This means that it uses calories. So if you have more muscle you are making better use of the food that you eat and can eat more. Having better muscle tone also helps to prevent injury by keeping all of our joints in a stable state.
I have just also been reading some research from the US that shows that resistance exercise, using weights, can actually reduce the signs of ageing in muscle. This small study showed that a 6 month resistance training programme changed the genetic expression of muscle to that of a younger person.
This study measured the genetic messages for mitochondria in the muscle tissue. Mitochondria are the power houses of any animal cells. They are the tiny organs inside the cell that actually use all the raw materials that we put into our body and convert these into the energy that the cell needs to function. As we grow older some of the genetic messages relating to mitochondria become scrambled and as a result the mitochondria don't work properly. The muscle tissue then doesn't get the energy that it needs and it starts to decay. This results in the muscle wastage that we experience past 30.
What this study found was that after a six months of programme of resistance exercise, the genetic messages for the mitochondria found in the older subjects more closely resembled those found in the younger subjects. What this means is that there is a fundamental change in how the muscle cells are controlled at the genetic level. This is very exciting news. We did not previously know that we could affect genetic messages with exercise.
What we don't know is whether its the genes themsleves that are changed or the mechanisms that allow them to do their work inside the cell. More work in the future may well answer that question.
So the message is clear. Exercise is good for you at an even deeper level than we had first thought. Here is the link to the original paper in the Public Library of Science.