Aging is associated with declining muscular strength. However, research demonstrates that older individuals can increase strength by resistance training. Although improvements were initially attributed to neural mechanisms, muscle hypertrophy has now been documented, even in nonagenarians. In terms of performance, reported increases have been as high as 227% for dynamic lifting, with more moderate gains in static strength tests. More research is needed to confirm what functional improvements result from increases in strength and muscle mass. This article examines the extent and mechanisms of strength changes, potential benefits, and programming implications for high-intensity strength training in older adults.