Actually, all parts of the human body are vulnerable, but while working out, certain specific types of injuries are commoner than others and, as the saying goes: forewarned is forearmed. Follow a warm up routine specifically for the body parts you are going to exercise right before you exercise them. This could be a lightweight set with weights at 30% of what you would be using normally.
The Neck – Mastoid Muscles
You can badly hurt your neck if your body alignment is incorrect when doing overhead presses. It does not matter whether you are using lifting heavy or light. Just remember to look straight ahead, and you can avoid this. As with any other exercise, make certain also that you are standing on perfectly level ground. Perform in front of a mirror to ensure both arms are lifting equally. Any flaw in form is usually paid for by the mastoid muscles.
The Shoulders – Deltoid and Rotator Cuff
It is possible to cause a very long lasting injury to your delts while doing the Bench Press. This could happen if your arms are not coordinating properly and one of them is handling more stress than the other. It could happen if you have not gripped the bar properly. It will most certainly happen if you have not flexed your muscles properly for the Press. Everything from your fingers to toes must be ready for the lift. A weak link anywhere will affect the delts because they are bearing the most pressure. This type of injury is dangerous because you will feel the affected arm go limp. Always have a spotter standing by, and never forget the warm up sets.
The Wrist – Ganglion and Bone Injuries
A ganglion is a fluid filled sac that appears at the juncture of wrist and palm and is visible as a lump or cyst. The fluid creates pressure on the nerves and this can be a very painful experience. In addition, a ganglion will make it difficult to perform ordinary activities, leave alone lifting weights. I got my ganglion when doing bodyweight Tricpes Back Press. The pressure is borne directly by the wrists.
Always remember to warm up your wrists before performing this item. Remember also to use good quality wrist straps while performing any exercise. These are not fashion accessories: they keep the small bones in the wrists aligned under pressure to minimize chances of injury. If you should still hurt yourself, put on an ice pack immediately and go see a doctor.
Other precautions are keeping your wrists straight with most lifts and presses, and bending them in a controlled manner when you do have to have them bent. The end point of Front or Back Press are instances where you should bend your wrists to cradle the bar properly – do it so that you are in control at all times.
The Lower Back
I don't think this one needs much elaboration. Just use a belt and adopt correct form when lifting anything, anywhere, and you will avoid injuring your back. Keep back strengthening items like the Deadlift as part of your regimen.
You don't normally hear of strained abs, but they exist, trust me, and you probably don't want a personal experience on this one. For one, you can't possibly keep your midsection immobilized, which means you are going to feel the pain at almost all times, and that it is going to be a slow recovery. See a doctor, and try not to do anything that hurts the abs further.
It is not necessary that ab workouts must cause such strained muscles. You could strain them shoveling the driveway or reaching for grocery at the Supermarket. Apart from the obvious precautions like warm up and gradually increasing reps or weight, the most effective way of preventing strained is to follow a proper ab workout regimen. Ask your instructor what would suit you best.
The legs are not normally injury prone although you could cause damage to your knees if you are lifting or squatting improperly. This is common with overweight individuals because they are always lifting an excess of bodyweight – their own.
A final word on the subject: try not to panic if an injury does occur while you are training in spite of taking precautions. I have lived with injuries for so long that I no longer notice them. After a while, you learn to live with them and your body learns how to avoid movements that put pressure on them. However, that is no excuse to be reckless. Any injury will get worse with age, and since you can avoid most of them with a little bit of attention to what you are doing, please channel your enthusiasm into safety measures first.