Low levels of physical activity have long been established as a risk factor for type 2 diabetes but researchers are still unsure of just how big a difference physical exercise can make to the risk.

A study published by researchers from Copenhagen, Denmark and Cleveland, Ohio has studied the effects on metabolism of low physical fitness as shown by low levels of VO2 max. VO2 max is a measure of the maximum volume of oxygen that a person’s body can consume during exercise and is therefore a good way of measuring cardiorespiratory fitness.

313 participants of varying age, sex, BMI and blood glucose control took part in the study and underwent measurements of VO2 max, body composition, HbA1c, fasting plasma glucose, and glucose tolerance.

The researchers found that people with low physical fitness (low VO2 max) had higher HbA1c levels, higher fasting blood glucose levels and low glucose tolerance (as shown by high blood glucose levels after 2 hours of a glucose tolerance test).

The research is significant in that low levels of physical fitness lead to impairments in blood glucose control across the whole range of participants, including those with healthy weight and those that are overweight.

The study therefore sends out the message that increasing physical fitness has benefits on glucose tolerance for all people whether they have diabetes or not.