Inclusion Criteria:  Age between 65 and 85 years No use of hormonal replacement therapy (women) No hospital admissions within the last 3 months Sarcopenia criteria:  (1) Muscle mass: measured by using InbodyS10 and standardized by height, shown by skeletal muscle index [SMI=appendicular muscle mass (kg)/height (m2)]. Low muscle mass was defined as:  Men: SMI <7.0 kg/m2 Women: SMI <5.4 kg/m2 (2) Handgrip strength: measured by electronic hand grip dynamometer. Low handgrip strength was defined as: Men: <28 kg Women: <18 kg (3) Limb strength: measured by Time for 5 times for chair stand method. Low limb strength was defined as: Time for 5 times for chair stand: ≧12s Sarcopenia was defined by (1), (2) or (3)  Exclusion Criteria:  Active cancer: currently receiving cancer treatment or have received cancer treatment within the last 3 months Weight change ≥ 5% or weight change ≥ 5 kg within the past 3 months BMI > 35 kg/m2 Disease requiring chronic use of prescription corticosteroids History of ischemic or hemorrhage stroke Unstable or uncontrollable hypertension (>180/110 mmHg) Doing hemodialysis or peritoneal dialysis within the last 3 months Participation in a structured physical exercise training program within the past 2 year; previous use of creatinine supplementation; use of drugs that can affect bone metabolism (e.g., glucocorticoids, bisphosphonates, vitamin D or calcium). Antibiotics were used in the past 3 months. Products of probiotic were used in the past 2 weeks. Living abroad for one month in the past 3 months Hyperthyroidism without medication therapy Allergic to milk