Sources & References

Anatomy (MedlinePlus)

U.S. National Library of Medicine (NIH)

License: Public domain (U.S. government work); some linked images may be third-party.

Last checked: 2026-07-19

URL: https://medlineplus.gov/anatomy.html

Plain-language government health information. Verify individual image licenses separately.

Bones, Joints and Muscles (MedlinePlus)

U.S. National Library of Medicine (NIH)

License: Public domain (U.S. government work); some linked images may be third-party.

Last checked: 2026-07-19

URL: https://medlineplus.gov/bonesjointsandmuscles.html

National Institute of Arthritis and Musculoskeletal and Skin Diseases

NIH / NIAMS

License: Public domain (U.S. government work) unless otherwise noted.

Last checked: 2026-07-19

URL: https://www.niams.nih.gov/

Musculoskeletal health and safety information.

Physical Activity Basics

U.S. Centers for Disease Control and Prevention (CDC)

License: Public domain (U.S. government work).

Last checked: 2026-07-19

URL: https://www.cdc.gov/physical-activity-basics/

Physical Activity Guidelines for Americans (2nd edition)

U.S. Dept. of Health & Human Services (ODPHP)

License: Public domain (U.S. government work).

Last checked: 2026-07-19

Published: 2018

URL: https://odphp.health.gov/our-work/nutrition-physical-activity/physical-activity-guidelines

Anatomy and Physiology 2e

OpenStax, Rice University

License: CC BY-NC-SA 4.0

Last checked: 2026-07-19

Published: 2022

URL: https://openstax.org/details/books/anatomy-and-physiology-2e

Peer-reviewed open textbook. License is NON-commercial + ShareAlike — reused text/images are NOT cleared for commercial use. Record attribution per passage.

ACSM Official Statements

American College of Sports Medicine

License: © ACSM. Only publicly available statements are referenced; no paid textbook content reused.

Last checked: 2026-07-19

URL: https://acsm.org/education-resources/pronouncements-scientific-communications/official-statements/

ACE Certification Exam Content Outlines

American Council on Exercise

License: © ACE. Public exam content outline used only to organize study domains; no proprietary questions reused.

Last checked: 2026-07-19

URL: https://www.acefitness.org/fitness-certifications/certification-exam-content/

NASM Certified Personal Trainer Exam Information

National Academy of Sports Medicine

License: © NASM. Public exam information used only to organize study domains; no proprietary questions reused.

Last checked: 2026-07-19

URL: https://www.nasm.org/certified-personal-trainer-exam-info