A longitudinal study that gathered data from more than one million people over 11 years found clear relationships between exercise and reduced risk of cancer.

The study, published in the Journal of the American Medical Association, is considered particularly significant not only for the length of the study and number of participants, but for the very direct links between exercise and certain types of cancer.

The major finding: People who exercised regularly during their leisure time at a fairly high level showed the following reduced risk of these cancers:

• Esophageal adenocarcinoma: 42 percent lower risk

• Liver: 27 percent lower risk

• Lung: 26 percent lower risk

• Kidney: 23 percent lower risk

• Gastric cardia: 22 percent lower risk

• Endometrial: 21 percent lower risk

• Myeloid leukemia: 20 percent lower risk

• Myeloma: 17 percent lower risk

• Colon: 16 percent lower risk

• Head and neck: 15 percent lower risk

• Rectal: 13 percent lower risk

• Bladder: 13 percent lower risk

• Breast: 10 percent lower risk

The average age of those in the study was 59; none had been diagnosed with cancer at the outset of the study.