The goal of this clinical trial is to explore whether the bioindicators of body composition, nutrition-related indicators (lymphocytes, albumin), lipids, and thyroid hormones are associated with sarcopenia and the changes in these indicators after an intensive lifestyle intervention. The main questions it aims to answer are:

• whether the bioindicators such as lymphocytes, albumin, lipids, thyroid hormones, fat mass, fat-free mass, and basal metabolic mass are associated with the development of sarcopenia.
• the changes of these bioindicators that occur in older adults after going through an intensive intervention.

Participants will receive a 3-month intensive intervention consisting of an intensive nutritional intervention and an individually designed exercise intervention. Nutritional and exercise prescriptions are co-designed through a nutritionist and rehabilitation physician.

Researchers will compare bioindicators in the sarcopenia group before and after intensive lifestyle intervention to determine the association with sarcopenia.

Inclusion Criteria:

• 1) Resident elderly aged 65-90 years old in the district.
• 2) Voluntary participation in the trial and signing the informed consent form.

Exclusion Criteria:

• 1) People with systemic severe diseases, organ failure, malignant tumors, neuromuscular degenerative diseases, or active weight loss.
• 2) People with cognitive impairment, incapacitation, or severe mental illnesses who cannot cooperate with the test.
• 3) People with cardiac pacemakers and artificial joint implantation or others who cannot undergo the BIA test.
• 4) People with severe cardiorespiratory dysfunction and physical disabilities who cannot complete the exercise training.
• 5) Incomplete data, refusal to participate in the survey, body composition analysis, and blood collection.