Table 1

Schedule of enrolment, interventions and assessments

Timepoint	Enrolment	Allocation	Postallocation
	Visit 1	Visit 2	Visit 3	Visit 4	Visit 5	Visit 6
	Screening (−4 to 0 week)	Baseline (0 week)	3 weeks±2 days	6 weeks±2 days	9 weeks±2 days	12 weeks±2 days
Enrolment
Consent	√
Inclusion and exclusion	√
Demographics	√
Medical history	√
Body height	√
Body weight	√
Blood pressure	√
Heart rate	√
BIA	√
Allocation		√
Interventions*
HMB nutritional supplement+calorie restriction
Placebo+calorie restriction
Assessments
Inclusion and exclusion		√
Body weight		√		√		√
Blood pressure		√		√		√
Heart rate		√		√		√
WC		√		√		√
HC		√		√		√
IPAQ-SF		√	√	√	√	√
FFQ		√	√	√	√	√
BIA		√		√		√
Sit-to-stand test		√		√		√
HGS		√		√		√
Blood tests†		√				√
Adverse events‡			√	√	√	√
Adherence‡			√	√	√	√

*Both intervention groups will also receive dietary instruction.
†The blood tests will include glucose metabolism (fasting glucose and insulin), albumin, haemoglobin, alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transpeptidase, cystatin C, creatinine, estimated glomerular filtration rate, lipid profiles and full blood counts.
‡Weekly WeChat or telephone contacts will be performed to assess adverse events and adherence (including dietary compliance).
BIA, bioimpedance analysis; FFQ, Food Frequency Questionnaire; HC, hip circumference; HGS, hand grip strength; HMB, β-hydroxy-β-methylbutyrate; IPAQ-SF, International Physical Activity Questionnaire Short Form; WC, waist circumference.