If I could only do one exercise to get in the best shape of my life, I'd do squats. Squats are so productive that they force the entire body respond by building muscle, improve conditioning, and increasing your cardiovascular ability. They have what's called secondary growth factors in that you're not just going to get bigger muscles in your legs. If you want bigger arms it's not going to happen without doing squats. Same goes for chest and shoulders. Squats aren't just for men either. If women want to get the best buns and legs ever, they need to do Squats!
Why? Because your legs are the largest muscle group, when you work them hard it sends a signal that the rest of the body needs to respond. Not only that, research as proved that the body produces more testosterone and growth hormone naturally after doing squats. This helps with building more muscle, losing fat, and vitality.
The problem with squats is that they are very hard! It's rare that you find the squat racks full when you go to the gym. People try and substitute easier exercises like leg presses in hopes to get the same results. It'll never happen because the squats have all of the other benefits that I discussed.
Here's how to do them properly:
The best results for building muscle from squats is when their done to parallel with with a rep range of 15-20. Pick a weight you normally would do for 8-10 reps, then mentally push yourself to doing 15-20. Just as with any exercise, squats are to be done slowly and smoothly with the fullest range of motion possible.
First, before you even put the bar on your back you should take a few minutes to contemplate the meaning of life, family, kids, why you're here, the universe etc. I'm being serious because after the first few reps, you'll want to stop. You want to make sure you're properly motivated. Visualize your goal and a successful set of 20 reps. Place the bar on your upper back, not your neck, and un-rack the bar, your feet shoulder width or just slightly wider, toes pointing straight ahead. Ideally you want your shoulders, knees, and feet to form a perfect vertical line. Taking a extra wide stance puts stress on the joints.
Ready now...Take a deep breath, tighten your abs, then slowly lower yourself to where your upper thigh is parallel to the ground. Stop yourself at the bottom position for a half second and slowly press through your heels squeezing your glutes to the top position exhaling as you go up. It should take you about 2-3 seconds to go down and 2-3 seconds up to do one rep. As you press up, the shoulder line and the hips should raise at the same time. Sometimes you'll find that your hips move first then your shoulders which puts more stress on your lower back. Squats to parallel take tremendous flexibility so you might have to practice them in a shorter range of motion until you gain the flexibility. As you lower, you'll notice your toes will start to turn out if you're not flexible enough. Don't go deeper than that and return to the standing position.
When you get past reps 8-10, you should be breathing like a freight train! You'll be needing at least 5 breaths before you go down for the next rep. During reps 14-18, your "higher power" should be talking to you. You may even be "seeing the light". By that point there's no turning back, you made it this far, you can't possibly stop until you get to 20 reps. One or two sets is all that is needed.
For those who may have an injury and that limit the ability to do parallel squats you can modify the exercise. Start off by leaning against a wall with and exercise ball on your lower back. This gives you support and keeps your back vertical to the ground. Do an even slower tempo by taking 4 secs to lower, pause at the bottom for 2 secs, and raise for 2 secs. When you can do 20 reps, hold a pair of light dumbells to increase the resistance.
Putting your effort into squats will reap rewards far greater than any other exercise. Dedicate yourself to 1-2 sets of 20 rep squats in your 3 weekly workouts and you'll quickly see why they're considered the best muscle building exercise.