This is a study to assess the safety and bioeffect of REGN1033 (SAR391786) in healthy volunteers.

Inclusion Criteria:

1. Males and postmenopausal females aged 60 years and older with no significant health issues or clinically significant abnormal laboratory values.
2. Low activity lifestyle
3. Diet and exercise adherence

Exclusion Criteria:

1. Significant concomitant illness such as, but not limited to cardiac, renal, rheumatologic, gastrointestinal, hematological, skeletal/muscular, neurologic, psychiatric, endocrine, metabolic or immunological disease.
2. Participation in any clinical trial within 6 months prior to screening.
3. Hospitalization, immobilization, or major surgical procedure requiring general anesthesia within 6 months prior to screening, or any planned surgical procedures during the study period.
4. Limb amputation (except for toes) and/or any fracture within 6 months.

The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial and not all inclusion/ exclusion criteria are listed.