Runners aren’t exactly famous for racing to the weight room. (“I’ll bulk up and slow down! Waaah!”) That’s a damn shame. Not only will lifting actually help improve your lean body mass (so you have less fat weighing you down), it’ll also do three more awesome things:Knock Seconds Off Your Time
Research shows that a plyometrics (explosive resistance) program can boost your finish time (for a 5-K specifically) by 3.1 percent, thanks to a surge in muscle power. Try dumbbell jump squats.