Optimizing Strength Training in Older Adults

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)