1. Behind-the-Head Lat Pulldowns
In the “old days,” people were actually taught to pull the bar behind their heads when doing a lat pulldown exercise—and many people still do that today. Bad idea. The problem? Only people with extremely flexible shoulder joints can do this behind-the-head movement safely, and even they have to be very careful about not hitting the back of their necks with the bar. In addition, almost anyone who spends their days deskbound is likely to have rounded shoulders or poor posture—a symptom of poor shoulder flexibility (among other things), making this exercise a no-no.
The Alternative: You can still work your lats without the risk of behind-the-head pulldowns by pulling the bar down in front of you. Sit with your spine straight, abs pulled in, and then lean your torso back slightly, keeping your spine straight. Pull the bar down towards your chest, but not below your collar bone.
2. Squats or Leg Presses with Deep Knee Bends
Whether you’re doing basic squats on your own or using a leg press machine, it can be very dangerous to bend your knees too deeply. The Problem? When your knees bend too deeply, your spine cannot maintain proper alignment. When that happens, the pelvis tilts and the lower back begins to take over, increasing the risk of strain to your lower back muscles or damage to spinal discs. In addition, bending your knees too deeply can injure or damage your knees, especially if you have knee problems.
The Alternatives: Squats and leg presses are generally safe and effective when done properly. But you should never bend your knees or hips more than 90 degrees during these exercises. Here’s an example of proper form when doing a leg press machine, but this can apply to squats with a barbell, and the sled machine, too.
3. Seated Leg Extensions
This is a very popular exercise for targeting the muscles on the front of your thighs (quadriceps). The Problem? This exercise poses major risks to the knees. Lifting heavy weights in this position (with all the resistance focused at your ankles), is not what the knee was designed to do. If you have any kind of knee problem, or use a too much resistance during this exercise, you can easily run into big trouble.
The Alternatives: Simple squats and lunges, with or without added weight, will work your thigh muscles naturally, safely and effectively. If you want to expand on these exercises (to develop explosive force for sports like soccer, basketball, or volleyball, for example), try sport-specific plyometrics. If you can’t do lunges and squats because you lack the leg strength, start with simple ball squats or modified “mini” lunges, and only lower yourself part way, gradually increasing your range of motion as you get stronger.
4. Inner and Outer Thigh Machine Exercises
These machines are pretty popular in most gyms. Both involve sitting with your knees bent in front of you. The adduction machine is designed to target the muscles of the inner thighs, and the abduction machine helps target the outer thigh muscles. The Problem? Using your inner and outer thighs to lift weight while in a seated position puts you at risk of straining these relatively small muscles and aggravating lower back and hip problems. In addition, your inner and outer thigh muscles are designed to support movement, not to be prime movers like they are in these types of exercises.
The Alternatives: The best way to target these muscles safely is with body weight exercises, such as standing adduction, standing abduction, lying adduction andabduction exercises, Pilates exercises, or similar movements that use resistance bands or the cable cross machines. Always start with a weight you know you can handle, and add resistance gradually.
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