Men with high cardioresjsonary fitness may have protection against 9 types of cancer

Good cardiorespiratory fitness at a young age is linked to a reduced risk of developing 9 specific cancers later in life, at least in men, according to a large long-term study published online in the British Journal of Sports Medicine.

The types of cancer associated with good cardiorespiratory fitness include head and neck, esophagus, stomach, pancreas, liver, bowel, kidney, and lung cancer.

Cardiorespiratory fitness is defined as a person’s ability to do aerobic exercises like running, cycling, or swimming for extended periods, and even climbing stairs. It is known to be linked with lower risks of certain cancers, but there have been few large, long-term studies on multiple cancer sites.

The researchers used Swedish registry data up to 2019, covering information, diagnoses, and deaths for conscripts who started their military service between 1968 and 2005.

At the start of their stint, when they were aged between 16 and 25, conscripts underwent standard assessments including height, weight (BMI), blood pressure, muscular strength, and cardiorespiratory fitness.

Conscripts with low levels of cardiorespiratory fitness were slightly more likely to be obese and have a history of alcohol and substance misuse, with parents with lower educational attainment. Of those assessed, 365,874 had low fitness, 519,652 had moderate fitness, and 340,952 had high fitness.

Over one million men (1,078,000) were included in the final analysis, 84,117 of whom developed cancer in at least one site over an average monitoring period of 33 years.

Compared with men who had low fitness at conscription, higher cardiorespiratory fitness was associated with a decreased risk of specific types of cancer. The lower risk percentages associated with different cancer types were detailed in the study.

The researchers cautioned that this is an observational study, so no firm conclusions can be drawn about cause and effect. Additionally, it is noted that the study did not have full data on other risk factors such as diet, alcohol intake, and smoking.

Despite this, the findings are in line with the American Society of Clinical Oncology guidelines on exercise during cancer treatment, and may be useful in public health policymaking and interventions aimed at increasing cardiorespiratory fitness in youth.