From Runners World.com
Keep these vital parts of your body healthy.
By Ted Spiker
The powerhouse muscles of our hips and thighs drive us forward, ensure we land safely, and help keep our knees and feet in proper working order. To handle such a big job, hamstrings, quadriceps, and glutes need to be in top form. Here's how to keep them healthy
Runners know how to rank their body parts. Most vulnerable? Knees, for sure. Most tortured? Feet. We've got the blisters and black toenails to prove it. Most powerful? When it comes to speed, endurance, and the diesel that gets us uphill, downhill, and everywhere in between, most of us would find it hard to credit anything other than our thighs. And for good reason. The powerhouse muscles that make up our upper legs drive our running--whether we're sprinting 100 yards or battling through 26.2.