According to a meta-analysis published in the Journal of the American Medical Association, the answer is “yes.” The study, which included 33 trials that involved more than 187,000 healthy men and women, showed that better cardiorespiratory fitness was associated with a lower risk of all-cause mortality and coronary heart disease (CHD). Participants took an exercise cardiac stress test, and researchers measured their maximal exercise capacity, as expressed in METS (the amount of energy needed to complete a task; for example, sitting requires 1 MET, walking 2 mph or 1 mile in 30 min. requires 2.5 METS, jogging 5 mph or 1 mile in 12 min. requires 7.5 METS). Participants who, during the stress test, had a maximal exercise capacity of 7.9 METS or more had substantially lower rates of all-cause mortality and coronary heart disease events compared with those who had a maximal exercise capacity of less than 7.9 METS. The researchers determined that in order to see a lowered risk of mortality and CHD, the minimum cardiorespiratory fitness levels for men were as follows: 9 METS at age 40, 8 METS at age 50 and 7 METS at age 60. For women, the minimum levels were: 7 METS at age 40, 6 METS at age 50 and 5 METS age 60. The authors stated that for every 1-MET higher level of maximal aerobic capacity, there is a 13% decrease in all-cause mortality and a 15% decrease in CHD events.
What does this mean to us?
Having a higher fitness level, as measured by peak exercise performance, results in a lower risk of death for any reason and a lower risk of having a coronary heart problem. The threshold appears to be 7.9 METS (being able to jog at 5 mph, or the equivalent, at maximal effort); however, MET levels are higher when we are younger and decrease as we age.
Kodama S, Saito K, Tanaka S, et al. JAMA. 2009;301:2024-2035.