1. The Weighted Lateral Lunge:
This is your classic physical education class stretch, but it works wonders on hip and ankle flexibility- especially when weighted. Now, what you want to do is start with your feet next to each other while standing, then take your weight to about neck height, and lunge laterally to one side while keeping your trail leg straight, and its respective foot, firmly planted to the ground. When it comes to the leg that's actually bent, make sure your knee tracks over your toe, your foot is firmly planted to the ground, and you maintain a neutral spine. Now, if done post-workout, you can sit in this position for about 1-2 minutes and switch, or if done pre-workout then you can bounce up and down in this position to get the ankles and hips loose, or you can switch between each leg to dynamically warm up your lower body.
2. The Hip-Flexor Pump:
This by far is my FAVORITE hip flexor stretch and once again can be done post, or pre-workout. When doing this if you can't actually grab your foot, that's fine, there's always a regression to anything, including this stretch. Now, before you start make sure you have a mat under your knee to make it easier to put all the weight on that one side. Next, reach back and grab your foot, and while bringing your foot toward your butt simultaneously drive your hips forward while maintaining a neutral spine. If done right, you'll feel an intense stretch from the crease of your hips, to about where your quad ends. If you're doing this one pre-workout because your hips feel tight then its best to pump your foot toward and away from your butt to dynamically warm up your hips, such as you would do if you were to do continuous body weight squats. On the other hand, if you're doing it post-workout, make sure to hold this position for about 1-2 minutes and try to get deeper with every exhalation without hurting yourself.
3. Plate, Dumbbell, Kettle-bell Squat Hold:
Once again this can be done post or pre-workout. This one is simple, yet I find it to have the most dramatic effect of all stretches if done for an extended period of time. All you have to do is grab a weight, put it between your legs while standing with your feet in your squat position, and squat down with proper form. Sit here and hold this position for as long as you need, but be aware that if you do this stretch and you decide to come up I highly advise you come up from the squat with proper mechanics, and don't just drop the weight and shoot your butt into the air. With that being said, I personally do it whenever I feel tight before, during, or after a workout. It's a great stretch for the quads, hip flexors, groin and ankles if done correctly!
Now, I hope that you find these three stretches useful. If done correctly, for an extended period of time before and after a workout, you will see dramatic changes in your mobility and squat form. Enjoy and feel free to email me if you have any questions