Researchers from Cleveland Clinic have found that better cardiorespiratory fitness leads to longer life, with no limit on the positive effects of aerobic fitness.
They retrospectively studied 122,007 patients who underwent treadmill exercise testing at Cleveland Clinic between Jan. 1, 1991, and Dec. 31, 2014, to measure all-cause mortality relating to the benefits of exercise and fitness. The paper was published on October 19, 2018 in the Journal of the American Medical Association Network Open.
Researchers found that increased cardiorespiratory fitness was directly associated with reduced long-term mortality, with no limit on the positive effects of aerobic fitness. Extreme aerobic fitness was associated with the greatest benefit, particularly in older patients (70 and older) and in those with hypertension.
“Aerobic fitness is something that most patients can control. And we found in our study there is no limit to how much exercise is too much,” said Wael Jaber, M.D., Cleveland Clinic.
Recent observational studies19–22 have described adverse cardiovascular findings associated with habitual vigorous exercise and have raised new questions regarding the benefits of exercise and fitness. But this latest study found that extreme fitness provided additional survival benefit over more modest levels of fitness.
“We were particularly interested in the relationship between extremely high fitness and mortality” said Kyle Mandsager, M.D.
The patients were divided into five performance groups – elite, high, above average, below average and low. Elite performers were having aerobic fitness in the top two and half percent by age and gender, and demonstrated fitness levels comparable to endurance athletes. Long-term survival was adjusted for a patient’s age, sex, height, weight, BMI, medications and comorbidities.
On analysis by age, the survival benefit of elite versus high performance was most notable in older patients. In those over the age of 70, elite performers had a nearly 30 percent reduced risk of mortality compared to high performers. In younger age groups there was no statistical difference in outcomes between elite and high performers.
On analysis by comorbidities, all-cause mortality inversely related to cardiorespiratory fitness and was lowest in the elite performers. For those patients with hypertension, the elite performers again showed a nearly 30 percent reduction in all-cause mortality compared to high performers. For all other comorbidity subgroups there was no statistical difference in survival rates between the elite and high performers.
Here one must understand that this study analyzed findings over a large population, and individuals should always check with their doctor before joining an exercise program.
Cardiorespiratory fitness is a modifiable indicator of long-term mortality, and health care professionals should encourage patients to achieve and maintain high levels of fitness.