The Effectiveness of Strength Training and Self-management in Reducing Symptoms for Individuals With Knee Osteoarthritis

Introduction Osteoarthritis is a chronic, progressive degenerative joint disease that predominantly affects the knee. Common clinical manifestations include joint pain, stiffness, and impaired physical function, which often lead to diminished sleep quality and psychological well-being, ultimately compromising the patient's overall quality of life. Osteoarthritis is a common degenerative disease that predominantly affects patients with Knee Osteoarthritis (KOA). Symptoms include swelling, pain, stiffness, and functional impairment of the lower limb joints. Severe cases can result in muscle atrophy and long-term disability, making it a major global health burden. WHO data indicates that while 365 million people had OA by 2019, the number surged to 528 million by late 2023, marking a 113% increase since 1990. The disease is particularly prevalent in the aging population, affecting 73% of men and 60% of women over the age of 55. Knee OA is the most common subtype, followed by hip OA. In Taiwan, the prevalence rate grew significantly from 7.9% in 1994 to 15% in 2015. Despite the rate remaining steady at 15% through 2024, the absolute number of people suffering from OA pain exceeds 3.5 million and continues to grow, severely impacting their daily quality of life. As the primary weight-bearing joint of the human body, the knee is highly susceptible to osteoarthritis (OA) due to constant mechanical stress and activity. Clinical manifestations typically include joint pain, stiffness, swelling, and impaired physical function. The development of OA is significantly associated with age and gender, particularly among individuals aged 45-50 and older. Given the global trends of population aging and increasing obesity, the impact of OA on physical function and quality of life has become more pronounced, subsequently escalating the socioeconomic burden. Consequently, investigating the symptoms and determinants of knee OA, alongside the current implementation of strength training and self-management interventions, has become a critical area of concern.

Pain symptoms associated with KOA lead to prolonged impairments across physical, psychological, and social domains, which subsequently compromise mental health, sleep quality, and general well-being. NICE (2020) identifies aging, female gender, and obesity as the primary risk factors for joint degeneration. The resulting pain and mobility limitations have enduring effects; persistent joint stiffness and discomfort often lead to a decline in sleep hygiene and psychological health, eventually evolving into chronic conditions that diminish quality of life in later years. Pain in KOA is a complex, subjective experience, and empirical evidence suggests a reciprocal relationship where deteriorating sleep quality is linked to the progressive worsening of arthritic pain. As a form of chronic musculoskeletal pain, it frequently disrupts nocturnal sleep, causing significant disturbances. Specifically, pain prolongs Stage 1 of non-rapid eye movement (NREM) sleep and interrupts the deeper Stages 3-4 (slow-wave sleep), leading to sleep patterns that are characteristically shallow, abbreviated, and fragmented, especially among the elderly population. In addition to pharmacological and surgical interventions, therapies such as acupuncture, Tai Chi, and yoga have been empirically validated for managing the progression and symptom severity of Knee Osteoarthritis (KOA). Significant early evidence indicates that strengthening the knee joint and its surrounding musculature can delay the radiographic progression of degeneration. Consequently, implementing structured and effective exercise regimens for symptom management and rehabilitation is crucial before surgical intervention becomes necessary. Such programs not only alleviate arthritic symptoms but also facilitate the maintenance of optimal sleep quality, mental health, and overall well-being. Defined as a planned, structured, and repetitive form of physical activity designed to enhance or maintain physical fitness, exercise therapy is widely utilized due to its feasibility and cost-effectiveness. Current international clinical guidelines advocate for exercise as a first-line treatment for KOA. The prescription of these exercise programs should be tailored to the specific joint location, pain phenotype, disease severity, comorbidities, and the patient's baseline physical condition. Given the high prevalence of KOA, there is a critical need for accessible and cost-effective strategies; therefore, home-based exercise programs should be prioritized.

In a systematic review and meta-analysis by Guo et al. (2022), 15 clinical trials identified from databases such as PubMed, EBSCO, SportDiscus, Medline, and Web of Science (2000-2022) were analyzed. The findings revealed that structured exercise programs significantly improved pain, stiffness, and physical function in patients with KOA. Similarly, a Cochrane review of 55 studies across five major databases (MEDLINE, EMBASE, CENTRAL, CINAHL, and PEDro) concluded that exercise interventions yield moderate to significant benefits in pain reduction and functional improvement. Resistance training, in particular, has been shown to effectively alleviate pain. However, experts caution that ineffective or improperly supervised exercise regimens may exacerbate symptoms, resulting in poor clinical outcomes and diminished patient adherence; thus, the modality and frequency of exercise must be meticulously designed and managed (Peeler & Ripat, 2018). Despite these global findings, local research in Taiwan concerning the interplay between KOA symptoms, sleep quality, emotional well-being, and the efficacy of strength training and self-management remains sparse.

Study purpose This study aims to evaluate the effectiveness of a combined strength training and self-management intervention in enhancing the symptomatic, psychological, and functional outcomes of patients with knee osteoarthritis.

Study design A quasi-experimental design will be employed in this study to evaluate the effectiveness of the intervention. Data will be gathered through structured questionnaires administered both before and after the strength training program. The assessment will focus on several key variables: osteoarthritis symptoms, sleep quality, emotional well-being, and quality of life. These pre- and post-intervention measures will then be analyzed to determine the impact of the strength training program on the participants. The target population for this study will consist of patients with knee osteoarthritis (KOA). Consecutive sampling will be utilized to recruit participants from the orthopedic and rehabilitation outpatient departments of a public regional teaching hospital in southern Taiwan. Participants will be required to complete basic demographic forms and structured questionnaires both before and after the intervention.

Study Setting, Participants, Sample Size Estimation Inclusion criteria will be as follows: patients aged 45 or older diagnosed with symptomatic KOA by a physician, who are conscious, have normal hearing, and are capable of effective communication. Conversely, the exclusion criteria will include patients with severe inflammatory arthritis; those awaiting or having undergone unilateral or bilateral total knee arthroplasty; individuals with contraindications to exercise therapy; those who have received physical therapist-led exercise therapy or knee injections within the past month; and individuals diagnosed with psychiatric or cognitive impairments. Sample size estimation will be performed using G*Power 3.1.9.4 software, employing the "Means: Difference between two independent means (two groups)" test mode. With the effect size set at a medium level of 0.6, a significance level (alpha) of 0.05, and a power of 0.80 (Cohen, 1988), the analysis indicates a minimum required sample size of 90 participants. Accounting for an estimated attrition rate of 10%, the total sample size will be increased to 100 participants, with 50 individuals assigned to the experimental group and 50 to the control group.

Study Recruitment Process During recruitment at the orthopedic or rehabilitation outpatient departments, the study's objectives and the group assignment process will be explained to potential participants. After obtaining signed informed consent, participants will be randomly assigned to either the experimental or control group using computer-generated randomization. Participants will be aware of their group assignment. Both groups will receive health education through a "Knee Osteoarthritis Self-Management Course" (with an online instructional URL provided for home viewing). The experimental group will additionally receive a "Home-Based Strength Training" intervention, while the control group will maintain conventional routine care. Prior to the intervention, baseline data will be collected from both groups. The demographic data will encompass age, gender, education level, marital status, religious beliefs, occupation, level of social support, smoking and alcohol history, history of knee osteoarthritis and pain, medication history, and comorbidities. The assessment scales will include the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), PSQI, HADS, and the EQ-5D-3L.

• Intervention for the Experimental Group: Participants in the experimental group will receive a 23-30 minute demonstration and explanation of the "Home-Based Strength Training" program. The session will begin with warm-up exercises. All movements will be performed slowly and steadily, avoiding rapid or sudden motions to prevent injury. The intervention consists of three primary components:

• Knee Muscle Endurance Training (Two sets): Step-ups and Step-downs: Participants will perform 20 steps each, using stairs or a platform. Starting with feet shoulder-width apart, participants will step up ensuring the knee aligns with the toes without overextending. The movement will be driven by the anterior leg muscles. For step-downs, participants will descend slowly, maintaining knee-toe alignment and stability. Sit-to-Stand Exercises: Participants will perform 10 repetitions per set. Using a stable chair of appropriate height (thighs and calves at a 70-90 degree angle), participants will stand up by driving through the legs while keeping the back straight and knees slightly flexed upon standing. Frequency: 3 times per week, 8 sets per session, with a 2-minute rest between sets.
• Level-Ground Walking: Participants will walk for 30 minutes per session, 3 times per week, on flat, safe surfaces using appropriate footwear. The technique emphasizes a natural heel-to-toe strike, coordinated arm swinging, and steady breathing.
• Range of Motion (ROM) and Flexibility Exercises: Knee Extension: While seated with the back against the chair, participants will slowly lift one leg until the knee reaches 160-180 degrees of extension, then pull the heel back toward the seat. (Held for 20 seconds, 10 reps per set, 3 times per day).

Quadriceps Stretch: While standing and holding a stable surface for balance, participants will pull one ankle toward the glutes until tension is felt in the anterior thigh. (Held for 30 seconds, 10 reps per set, 3 times per day).

After the initial demonstration, participants will demonstrate the exercises back to the researcher. The researcher will provide corrections until the movements are performed correctly. Participants will be instructed to record their completion in an exercise log. Follow-up assessments will occur during the second clinic visit (1 month post-intervention) and the third clinic visit (2 months post-intervention), utilizing the WOMAC, PSQI, HADS, and EQ-5D-3L scales. Additionally, the researcher will conduct two telephone follow-ups and home visits as needed during the study period to monitor adherence.

• Control Group: The control group will receive conventional routine care on knee osteoarthritis self-care. Follow-up assessments will be conducted during the second clinic visit (1 month post-enrollment) and the third clinic visit (2 months post-enrollment). During these visits, data will be collected using the WOMAC Osteoarthritis Index, PSQI, HADS, and the EQ-5D-3L scale.

Ethical Considerations

• Data collection will commence only after the study protocol has been reviewed and approved by the hospital's Institutional Review Board (IRB No: PTVGH26-CT4-04) and administrative permission for recruitment has been obtained.
• Prior to recruitment, the attending physician will evaluate the patient's condition to ensure they meet the inclusion criteria. The physician will continue to monitor the participant throughout data collection. If a participant's condition fluctuates or deteriorates, data collection will be terminated immediately, and the individual will be excluded from the study.
• The study's objectives, methods, and procedures will be explained in detail to each participant and their family members. Data will only be collected after they have fully understood the information and signed the informed consent form.
• Participants will be informed of their right to refuse participation or withdraw from the study at any time without any adverse impact on the quality of their medical treatment or nursing care.
• To ensure confidentiality, all participant data will be processed using a coding system. Except for investigations required by law, participants' names and privacy-including collected data, test results, and diagnoses-will be strictly protected. All data will be destroyed after being securely stored for five years.
• If the research findings are published for academic purposes, participants' privacy (including names and medical record numbers) will remain confidential and will not be disclosed individually.

Data Processing and Statistical Analysis The demographic data and questionnaire responses collected in this study will be coded and entered into a computer database. Data management and statistical analysis will be performed using IBM SPSS Statistics version 26.0. The significance level for all statistical analyses is set at alpha = 0.05. In addition to descriptive statistics, the choice between parametric or non-parametric methods for correlational and inferential analyses will be determined after assessing the data distribution. A normality test (e.g., Shapiro-Wilk or Kolmogorov-Smirnov test) will be conducted to confirm whether the collected data follow a normal distribution.

Expected Contributions This study will employ a quasi-experimental design to evaluate the effectiveness of a strength training intervention in alleviating symptoms and improving sleep quality, emotional health, and overall quality of life among patients with knee osteoarthritis. The findings are expected to demonstrate the clinical significance of a feasible, home-based strength training program in reducing symptom severity and enhancing the well-being of KOA patients in Taiwan. Furthermore, the results will be prepared for publication in international peer-reviewed journals to facilitate knowledge dissemination within the global academic community and the general public. Beyond its academic contributions, this study will provide evidence-based insights to help healthcare authorities optimize treatment, care, and management protocols for KOA, ultimately contributing to reduced national healthcare expenditures. Finally, this program empowers patients to proactively self-manage their symptoms and promote long-term functional independence.

Inclusion criteria

• Age 45 or older
• Diagnosed with symptomatic knee osteoarthritis by a physician
• Normal hearing and able to communicate effectively

Exclusion criteria

• Severe inflammatory arthritis
• Pending or previous unilateral or bilateral total knee replacement
• Contraindications to exercise therapy
• Received physical therapy or knee injections in the past month
• Psychiatric or cognitive impairments