Early-onset type 2 diabetes (T2DM) may lead to very early vascular complications. Cardiovascular mortality is two to five times higher in adults with diabetes than in people without diabetes. The cardiovascular risk of young people with T2DM is unknown. T2DM in young people is associated with marked visceral obesity, insulin resistance and microalbuminuria. We recently showed that these subjects did not improve in either fitness (maximum volume of oxygen consumption, VO2max) or glucose disposal after exercise training. Seven subjects with early-onset T2DM (aged 26.1+/-0.9 years, body mass index [BMI] 35.6+/-1.2 kg/m2) and 14 age-matched obese subjects with normal glucose tolerance (aged 25.6+/-0.9 years, BMI 34.3+/-1.4 kg/m2) underwent aerobic training for 12 weeks. Serum vascular inflammatory markers (high-sensitivity C-reactive protein [hsCRP], soluble intercellular adhesion molecule [sICAM-1], soluble vascular cell adhesion molecule [sVCAM-1], E-Selectin and P-Selectin) were measured before and after the training programme. At baseline, plasma concentrations of vascular inflammatory markers were significantly elevated in both groups. They did not improve after exercise.