During their study, which included 2,603 adults age 60 years or older (average age, 64.4 years; 19.8 percent women), the researchers tried to examine the the associations between cardiorespiratory fitness, various clinical measures of adiposity (body fat) and death in older women and men.

In order to asses the fitness level the researchers used the treadmill exercise, while the adiposity level was assessed by body mass index (BMI), waist circumference, and percent body fat. Low fitness was defined as the lowest fifth of the sex-specific distribution of treadmill exercise test duration. There were 450 deaths during an average follow-up of 12 years.

The researchers found that those who died were older, had lower fitness levels, and had more cardiovascular risk factors than survivors. However, there were no significant differences in adiposity measures.

“… we observed that fit individuals who were obese (such as those with BMI of 30.0-34.9, abdominal obesity, or excessive percent body fat) had a lower risk of all-cause mortality than did unfit, normal-weight, or lean individuals. Our data therefore suggest that fitness levels in older individuals influence the association of obesity to mortality,” the authors write.

Based on their research, the authors concluded that the regular physical activity such as brisk walking for 30 minutes or more on most days of the week may reduce all-cause death rates among older adults, including those who are obese.

“Enhancing functional capacity also should allow older adults to achieve a healthy lifestyle and to enjoy longer life in better health”, the authors concluded.