Janet is an active 50 year old runner and she has been running for almost all her life. she visited her local physician for chronic concern of joint pain. after several visits, the physician is unable to diagnose her because she is showing symptoms of several disorders of the joints - arthritis, rheumatoid arthritis, osteoarthritis and bursitis. what are some similarities and differences between these disorders? do you think that janet's running habits contribute in any way to these disorders?

Similarities:
 joint pain
difference:
arthritis: inflammation of the joint due to premature wear of the cartilage.
rheumatoid arthritis, the disease but concerning several joint
bursitis: between two tendons, between the skin and tendon, or between a bone and tissue.

Sport submits the strained joints. With each movement, it creates pressure that crush the cartilage, but being active seems sufficient to preserve the musculoskeletal system.
Sporting activity preserves the musculoskeletal system.
Playing sports: golf, hiking, gentle jogging, cycling, swimming.

Sodium is the answer