I've read a number of new studies linking low aerobic fitness with all sorts of concurrent health problems. Yet there has also been work showing that low aerobic fitness is a predictor of future health issues.
This study shows that low aerobic capacity predicts subsequent increases in body fat in children. This study shows that low aerobic capacity predicts an increased risk of the metabolic syndrome five years later.
Aerobic capacity (vo2max) can be improved by a variety of aerobic exercise programs. Accumulating evidence suggests that improving aerobic fitness is vital for avoiding future health problems.