New research from Washington State University finds that consistent exercise is of benefit beyond general physical fitness and mental wellbeing change. The data demonstrates that exercise influences the very molecules in the human body that influence how genes behave.
The research is based on a study of twins. Studies of twins are used to assess a range of different theories about human development. The aim is often to reveal the importance of environmental and genetic influences for traits, phenotypes, and disorders.
The study finds that the more physically active siblings in identical twin pairs display lower signs of metabolic disease. This is as measured by waist size and body mass index.
The physical data is supported by differences in the epigenomes of the twins. These are the molecular processes that are around DNA and independent of DNA sequence and which influence gene expression. For this samples were collected from cheek swabs taken from 70 pairs of identical twins who also participated in an exercise study through the Washington State Twin Registry.
The Washington State Twin Registry is a database of twins who are interested in participating in health and behaviour-related research. Twin Registry members are invited to participate in new studies developed by prominent scientists around the world at various intervals.
Many of the twins studied were established to be discordant, differing from each other on measures of physical activity, neighbourhood walkability and body mass index. Hence the biological and physiological data relating to both sets of twins provided useful information for comparison.
The collected and analysed biological test data indicated that the more active twins had epigenetic marks linked to lowered metabolic syndrome (which relates to heart disease, stroke and type 2 diabetes). These conditions include increased blood pressure, high blood sugar, excess body fat around the waist, and abnormal cholesterol or triglyceride levels.
Given that the identical twins have the same genetics, the findings indicate that markers of metabolic disease are strongly influenced by how a person interacts with their environment as opposed to simply their inherited genetics.
According to lead researcher Michael Skinner: “The findings provide a molecular mechanism for the link between physical activity and metabolic disease”. The academic adds: “Physical exercise is known to reduce the susceptibility to obesity, but now it looks like exercise through epigenetics is affecting a lot of cell types, many of them involved in metabolic disease.”
The research appears in the journal Scientific Reports, titled “Epigenome-wide association study of physical activity and physiological parameters in discordant monozygotic twins.”
