The attempt to modify two behaviors simultaneously might have diluted the effect of both. "Qualitative interview results suggest that people use a trade-off system in which they reward themselves for additional exercise with increased food intake," Dr. Andrews and his associates commented.
"I found it a little surprising that there was no additional benefit of exercise, but perhaps it’s true that people didn’t adhere as well to the diet, or perhaps the diet is just so powerful in the beginning that exercise doesn’t add that much," observed Dr. Sue Kirkman, senior vice president of medical affairs and community information for the ADA.
Dr. Andrews added, "We’re not saying exercise isn’t useful. We’re saying exercise didn’t improve the parameters that we measured. There’s a lot of clear evidence that individuals who exercise have a reduced cancer rate, reduced mortality, and get other benefits from exercising like well-being. ... In this context if we want to get HbA1c better the first thing to do is concentrate on diet. We’re not saying don’t do exercise," he said in an interview.
"The Early ACTID trial shows clearly that intensive dietary support soon after the diagnosis of type 2 diabetes is beneficial. ... Our findings support the redesign of diabetes services to increase dietary management at an early stage. Because the intensive diet intervention was designed to be delivered by practice nurses with dietitian support, this approach could be translated into community-based services," they concluded.
The study was funded by Diabetes UK and the UK Department of Health. Two of the researchers reported financial relationships with companies including Bristol-Myers Squibb, GlaxoSmithKline, Medtronic, Novartis, Novo Nordisk, Sanofi-Aventis, and Eli Lilly.