Haenyeo diagnosed with knee osteoarthritis 2.8 years late... “Effects of Underwater Exercise”

It was found that Jeju's female divers, who have been collecting seafood from the sea for decades, were diagnosed with knee arthritis 2.8 years later than other women.

Jeju National University Hospital and Samsung Seoul Hospital's Clinical Epidemiology Research Center announced on the 10th that they established and analyzed a group based on approximately 20 years of clinical data of 16,763 women aged 50 or older who were diagnosed with knee osteoarthritis at Jeju National University Hospital from 2004 to 2023.

As a result of the study, the average age at which female divers were diagnosed with knee osteoarthritis was 69.4 years old, which was 2.8 years later than the average age of 66.6 years for women.

The prevalence of osteoarthritis among women over 50 years of age was 13.8% for female divers, which was only half of the 24.6% for general women.

The progression of osteoarthritis was also found to be slower in female divers.

In an item that used the point at which the knee joint is severely damaged and requires total joint arthroplasty (TKA) as an indicator of disease progression, the risk of female divers receiving artificial joint surgery was 14% lower than that of ordinary women.

This difference was especially noticeable in patients with the most radiologically severe grade 4 (K-L grade 4).

The female diver had a good recovery process after surgery. In an analysis of 3,925 people who underwent artificial joint surgery, the risk of readmission within 30 days after surgery was 29% lower for female divers, even though they were older and had more comorbidities than general women.

The research team determined that although divers dive dozens of times a day and do high-intensity labor by pulling up heavy nets, the buoyancy of water reduces the load on the joints and strengthens the muscles, so underwater activities act as low-impact exercise on the knee joints.

In addition, it was analyzed that the cardiorespiratory endurance and muscle strength that the female divers had developed through the material helped them endure the surgery well and recover quickly despite their advanced age and high burden of comorbidities.

This study was published in the international journal Occupational Medicine (IF=2.4).

Co-corresponding author Jindeok Joo, professor of neurosurgery at Jeju National University Hospital, said, "The female diver group is a rare research resource in the world that can study the effects of extreme occupational environments on the human body. It is significant that the joint-protective effect of underwater activities, which had been known only empirically, was objectively confirmed with actual large-scale clinical data."

Jo Joo-hee, director of the Clinical Epidemiology Research Center at Samsung Seoul Hospital, added, "Follow-up research is needed to determine how aquatic exercise can be used to prevent and manage knee osteoarthritis, which is common in older women."