• Aging: As people age, there is a natural decline in muscle mass, leading to decreased muscle strength and function.
• Physical inactivity or lack of exercise: Reduced physical movement or a sedentary lifestyle can accelerate muscle loss, causing muscle atrophy and weakness.
• Chronic health conditions: Diseases such as diabetes, heart disease, chronic lung disease, chronic kidney disease, or cancer can increase the risk of accelerated muscle loss.
• Both malnutrition and obesity states, as well as certain nutrient deficiencies such as vitamin D deficiency, can cause muscles to weaken. Older adults who are overweight or obese may have more fat infiltration in their muscles and experience a faster loss of quality muscle mass.
• Inadequate protein intake: If the body does not receive enough protein or essential nutrients, it becomes difficult to repair or build new muscle. Older adults often face challenges such as dental issues, digestive problems, or reduced appetite, which may lead to insufficient protein consumption.

In the early stages of sarcopenia, some older adults may not clearly notice any abnormalities. However, as the condition progresses, the key symptoms commonly observed include reduced muscle strength, difficulty standing up from a chair, slower walking speed, inability to stand or walk for long periods as before, poor balance, and increased risk of falling. Unintentional weight loss may also occur. In the long term, sarcopenia can affect overall health by increasing the risk of falls and fractures, raising the likelihood of hospitalization, and increasing the risk of death from other diseases or complications in older adults.

• Handgrip strength measurement: This involves using a handgrip dynamometer to measure grip strength. A grip strength lower than the standard threshold indicates a reduction in overall muscle strength.
• Muscle mass measurement: This can be performed using various methods, such as bioelectrical impedance analysis (BIA), which uses a mild electrical current passing through the body to calculate the ratio of muscle to fat.

• Exercise: Exercise is the most effective method to prevent and alleviate sarcopenia, especially resistance or strength training exercises such as weightlifting, resistance band workouts, and chair stand exercises.
• Proper nutrition and adequate protein intake: In addition to eating a well-balanced diet from all five food groups, it is essential to consume sufficient protein. The recommended amount is approximately 1.0-1.3 grams of protein per kilogram of body weight per day (e.g., an older adult weighing 60 kilograms should consume about 60-78 grams of protein per day).
• Vitamin D supplementation: Vitamin D deficiency in older adults is associated with reduced muscle mass and bone strength. Older adults can get vitamin D from sunlight, foods (such as fatty fish, egg yolks, and milk), or supplements as advised by a physician.
• Lifestyle modification and general health care: Avoid smoking and alcohol consumption, as they negatively impact muscle and overall health. Control and manage chronic diseases such as diabetes, high blood pressure, and joint disorders to keep symptoms stable, as poorly managed chronic conditions can accelerate muscle deterioration. Additionally, older adults should get enough rest, reduce stress, and be encouraged to engage in regular physical activities suited to their abilities (e.g., gardening, walking, or doing light housework) to help maintain muscle function.

• Cruz-Jentoft AJ, Bahat G, Bauer J, Boirie Y, Bruyère O, Cederholm T, Cooper C, Landi F, Rolland Y, Sayer AA, Schneider SM, Sieber CC, Topinkova E, Vandewoude M, Visser M, Zamboni M; Writing Group for the European Working Group on Sarcopenia in Older People 2 (EWGSOP2), and the Extended Group for EWGSOP2. Sarcopenia: revised European consensus on definition and diagnosis. Age Ageing. 2019 Jan 1;48(1):16-31. doi: 10.1093/ageing/afy169. Erratum in: Age Ageing. 2019 Jul 1;48(4):601. doi: 10.1093/ageing/afz046. PMID: 30312372; PMCID: PMC6322506.
• Cho MR, Lee S, Song SK. A Review of Sarcopenia Pathophysiology, Diagnosis, Treatment and Future Direction. J Korean Med Sci. 2022 May 9;37(18):e146. doi: 10.3346/jkms.2022.37.e146. PMID: 35535373; PMCID: PMC9091430.
• Cruz-Jentoft AJ, Sayer AA. Sarcopenia. Lancet. 2019 Jun 29;393(10191):2636-2646. doi: 10.1016/S0140-6736(19)31138-9. Epub 2019 Jun 3. Erratum in: Lancet. 2019 Jun 29;393(10191):2590. doi: 10.1016/S0140-6736(19)31465-5. PMID: 31171417.