The purpose of this study is to determine the frequency of colorectal cancer in male and female endurance athletes between the ages of 35 and 50.

Inclusion Criteria:

• Adult males and females 35-50 years of age

• Male and female self-reported endurance athletes, defined by at least one of the following:

  • Run at least two races of 50 miles or more
  • Run 5 races of 26.2 miles or more

• Ability to complete testing in the protocol and make study visits

• Able and willing to consent to protocol

Exclusion Criteria:

• Known or suspected history of inflammatory bowel disease, familial adenomatous polyposis (FAP), or Lynch Syndrome
• Concomitant illness that would prevent adequate patient assessment or in the investigators' opinion pose an added risk for study participants.
• Anticipated poor compliance
• Prisoners or subjects who are involuntarily incarcerated
• Persons with decisional incapacity/cognitive impairment
• Any history or evidence of severe illness or any other condition that would make the patient, in the opinion of the investigator unsuitable for the study
• Subject is involved with a worker's compensation, personal injury, or other legal matters related to their health
• Subject is enrolled in a separate interventional clinical trial

Potential participants will be recruited through distribution of a flyer at endurance events, chat rooms, and race invitations.