Like most physical activity in which repetitive or vigorous movement is involved, weight training can cause injuries. Yet, compared to other activities and sports like football, injury rates are relatively low. A study published in the Journal of Strength and Conditioning Research found that football, soccer and winter sports cause 10 to 20 times more injuries per 100 hours of participation than weight training and weightlifting.
You can avoid injury by using a cautious and knowledgeable approach to weight training exercise. Your technique, or how you perform the exercise, is crucial to minimizing injury. So are judgments about the type of exercise and the load you attempt to lift, push or press -- especially in relation to your existing fitness, strength, bone and muscle health, and injury status.
Let’s go through the most important performance safety issues in weight training, bearing in mind that "safety" is a comparative term -- what's dangerous for you may not be dangerous for someone with more experience, training or different body structure.
Beginners Versus Experienced TrainersWhen you exercise over time, the body builds strength, endurance, bulk and even flexibility and durability in tendons, ligaments and muscles. This progressive adaptation is called a “training effect,” and it’s one reason why you are encouraged to train regularly, consistently and with only gradual increases in intensity, load or time.
If you have been weight training for a long time, you are likely to be able to do exercises of greater complexity, and perhaps greater risk, than a beginner. Much of the information below is for beginners.
Your Flexibility and AnatomyWhether you can perform a particular exercise safely may depend on your existing bone and muscle structure, either inherent or as a result of past injury or accident. For example, I don’t barbell squat with the weight on the shoulders or do pulldowns with the bar behind the head. Even a slight rotation of the shoulder in this direction is uncomfortable and probably dangerous for me, as I have had rotator cuff injuries to both shoulders.
Be aware of positions, exercise types and loads that make you feel you are extending joints, ligaments, muscles and tendons too far beyond your natural range. Alternative exercises that work the same muscles often exist. Challenge yourself, but with common sense.
Perform the Exercise CorrectlyEach exercise has guidelines for correct form or technical execution. Make sure you comply with the general guidelines for good form. You can see how to do many basic exercises in the exercise gallery.
Overuse Versus Structural Injuries in Weight TrainingIf you exercise frequently and intensely enough, chances are you will get what’s called an “overuse” injury at some stage of your training. This often results from an overworked tendon, which can cause tendonitis. Tendons join muscle to bone. The injury may be trivial and respond to rest, or become a chronic problem. Overuse injuries are common in sportspeople and heavy exercisers, even though a brief curtailment of the exercise often improves the injury.
More serious injuries occur when a structure breaks or is worn away over time. Torn or strained muscles and ligaments, tendons pulled from bones, and worn out and broken cartilage that fails to protect bones from rubbing together generally present more serious problems for which medical treatment is usually required.
The Big Three Injury Sites
In weightlifting, the most injured areas are the lower back, shoulders and knees. Most related injuries are overuse injuries, and a smaller percentage are more serious. The lower back tops the list, however, and this is consistent across many sports. It no doubt signifies a human anatomical weakness.
In one study of professional weightlifters, the investigators said, "injuries typical of elite weightlifters are primarily overuse injuries, not traumatic injuries compromising joint integrity."
However, it would be a mistake to think that training with weights at a recreational and fitness level puts you at greater risk for these injuries than being sedentary. Gradual application of weight to the muscles and joints using good technique in an appropriate training program is likely to make you stronger and more resistant to injury than if you did no strength training. Even people with arthritis are finding that weight training improves rather than degrades their condition.
And although exercises like the squat do put pressure on knees, half squats, rather than full squats all the way down, are relatively safe done properly. Most knee injuries in sport derive from sudden twisting, hyperextension and side impact forces such as occur in football, basketball and winter sports rather than the knee flexing and extending under load in weight lifting.