you don't have to sprint. jenna: experience with age what you're saying. >> exactly. jenna: always comes up, especially when folks look at new exercises for year ahead. better to start running an jogging or is it better to hit the weights? interesting study looked at women and use of weight liftingg when it comes to specific disease. i know you're a lifter, dr. campbell. tell us about this particular study. >> we've known for a very long time, aerobic exercise, 150 minutes a week is very important to reduce obesity and heart disease and type 2 diabetes where your body doesn't respond to insulin well. in this study they added one hour a week of weight lifting. what they found in the women their rates of diabetes was very, very low. it seemed to increase lean muscle mass which made their ability to respond to insulin and resist development of type 2 diabetes. jenna: as a cross sitter, big take away from the studies is what? >> do something, get up, move. shake it up.