Does anyone know what exercises can be done at home to strengthen the muscles on the front of your legs? My knees crack when I walk and I get shin splints, I was told strengthening those muscles would help both problems. My doctor told me to hold the leg straight out while sitting and lift it up off the chair but I think that will only get me so far before it stops being effective.

You can start by doing that quad exercise, as you get stronger add a weight, then do it standing up by balancing on one leg, this way also works your core.

You can also work your quads and your whole leg with squats. Do a set of body weight squats, 10 or 12 reps, then do the above leg extension standing up. Alternate these two exercises and in no time you'll feel it.

Here's a nice site for knee pain exercises

Hope this helps keep us posted on your progress...

Wall sit isometric holds- put your back against the wall and slide down til it's like you're sitting in an invisible chair and sit there for time--as long as you can. Shoot for a minute, then two minutes, etc.

Great! Thanks guys

I just started doing Insanity from Beachbody and my legs are definately feeling it. It's intense but will get the job done. Fast I might add. I'm on week two and I feel like I could crush a man with my thighs but in the good way now.