Muscle expression of genes associated with inflammation, growth, and remodeling is strongly correlated in older adults with resistance training outcomes.

A group (n = 8) of healthy older (68 +/- 6 yr) adults participated in a 36-session progressive resistance exercise training program targeting the thigh muscles to determine the relationship between muscle gene expression and gains in muscle size and strength. Biopsies were obtained from the vastus lateralis at baseline 72 h after an acute bout of exercise and 72 h after completion of the training program. Training increased thigh muscle size (7%) and strength for the three exercises performed: knee extension (30%) and curl (28%) and leg press (20%).

Aging alters macrophage properties in human skeletal muscle both at rest and in response to acute resistance exercise.

Macrophages are involved in skeletal muscle repair through pro-inflammatory and alternative functions. We tested the hypothesis that aging alters the abundance and properties of skeletal muscle macrophages that will influence their functional response to acute resistance exercise. Total macrophages (CD 68+), as well as pro- (CD 11b+) and anti-inflammatory (CD 163+) subpopulations and associated cytokine mRNAs were quantified in vastus lateralis biopsies from young (N=17) and elderly (N=17) males pre- and 72 h post-exercise.