The objective of the current study is to determine whether lifting lighter loads close to failure improves strength training adaptations and function in older adults. The main questions it aims to answer are:

1. The effect of light loads on physical function
2. The effect of light loads on muscle mass, power, and strength

Researchers will compare a light-load, high-repetition program to a standard strength training program. Participants will perform supervised strength training twice per week for 20 weeks.

Inclusion Criteria:

• Males and females aged 65 years and above
• Inactive lifestyle (< 150 min per week of moderate intensity physical activity) and not regularly participating in a structured strength training program
• Planning to reside in the area for the duration of the study

Exclusion Criteria:

• Severe cardiac disease, including Class III or IV congestive heart failure, clinically significant aortic stenosis, history of cardiac arrest, use of a cardiac defibrillator, or uncontrolled angina
• Lung disease requiring either oral or injected steroids, or the use of supplemental oxygen
• Short, portable mental status questionnaire with 3 or more errors
• Severe arthritis (either osteoarthritis or rheumatoid arthritis)
• Cancer requiring treatment in the past 1 year (melanomas excluded)
• Development of chest pain or severe shortness of breath during the 6 min self-paced walk test
• Parkinson's disease or other serious neurological disorders
• Renal disease requiring dialysis
• Current diagnosis of schizophrenia, other psychotic disorders, or bipolar disorder
• Current consumption of more than 14 alcoholic drinks per week
• Severe lower back or shoulder pain that may worsen with weightlifting exercises
• Undergoing physical therapy involving the lower extremities
• Living in nursing homes, assisted living facilities or other similar institutions
• Currently enrolled in another randomized trial involving a pharmaceutical or lifestyle intervention
• Weight change (intentional or not) over the last 6 months of > 5% of body weight, or plan to lose or gain weight during the study
• Any other cardiovascular, pulmonary, orthopedic, neurologic, or other conditions that would preclude participation and successful completion of the protocol

Temporary Exclusion Criteria

A person meeting any of the following temporary exclusion criteria at the time of screening will not be enrolled but may be re-screened later.

• Severe hypertension, e.g., SBP > 200 mm Hg, DBP > 110 mm Hg
• Major surgery or fracture or hip/knee replacement within the last 6 months
• Hospitalization within the last 6 months (excluding ER visits)

Statistician