Defining Clinical Endpoints in Limb Girdle Muscular Dystrophy (LGMD)

Inclusion Criteria - Arm 1: * Age between 4-65 at enrollment * Clinically affected (defined as weakness on bedside evaluation in either a limb-girdle pattern, or in a distal extremity) * A genetically or functionally confirmed mutation in ANO5, CAPN3, DYSF, DNAJB6 or SGCA-G. * Willing and able to give informed consent and follow all study procedures and requirements Inclusion Criteria - Arm 2: * Age between 4-65 at enrollment * Clinically affected (defined as weakness on bedside evaluation in either a limb-girdle pattern, or in a distal extremity) * a genetically confirmed mutation in SGCA-G * Willing and able to give informed consent and follow all study procedures and requirements Exclusion Criteria - Arm 1: * Any other illness that would interfere with the ability to undergo safe testing or would interfere with interpretation of the results in the opinion of the site investigator. * History of a bleeding disorder, platelet count \<50,000, current use of an anticoagulant. * Positive pregnancy test at time any timepoint during the trial. Exclusion Criteria - Arm 2: * Any other illness that would interfere with the ability to undergo safe testing or would interfere with interpretation of the results in the opinion of the site investigator. * History of a bleeding disorder, platelet count \<50,000, current use of an anticoagulant * Positive pregnancy test at time any timepoint during the trial.