The purpose of this study is to investigate if preoperative strength training will result in faster recovery and higher level of function six weeks after total knee arthroplasty (TKA).

Reduced strength of the quadriceps muscle is a common clinical finding in patients with Knee Osteoarthritis and this seems to play a central role in the development of the disease. The strength of the quadriceps muscle have been shown to be reduced by 20-40% as compared to age-matched healthy controls and this decrease in muscle strength have been closely associated with a reduced level of function and increase of pain. Furthermore, it has been demonstrated that the preoperative strength of the quadriceps muscle in patients undergoing TKA, is associated with the level of function one year after surgery. Compared to the level before the operation, an additional operation-induced reduction of the strength of the quadriceps muscle up to 60% as has been demonstrated. Presumably, an optimizing of the strength of the quadriceps muscle could counteract the impact of the expected postoperative loss of muscle strength to such an extent that the loss will be of less clinical significance. It is hypothesized that an optimizing of the strength of the quadriceps muscle may have a favorable effect on the postoperative rehabilitation program and shorten the period of convalescence.

Inclusion Criteria:

• Planned TKA at the Aarhus University Hospital or Region Hospital Silkeborg,
• Living in Aarhus Municipality,
• Primary knee osteoarthritis or secondary osteoarthritis after meniscectomy or ligament injury

Exclusion Criteria:

• Unstable blood pressure,
• Neuromuscular or neurodegenerative disease,
• Comprehension or dementia problems