The American Journal of Sports Medicine reported that the number of people ending up in the emergency room due to weight lifting injuries is steadily increasing. Although men are more prone to get injured (I can guess why), the rate of injury is increasing faster among women. You can find a good recap of the study and other related data in an article by Nicholas Bakalar in the NY Times (I first learned of it at www.sportsgeezer.com, a good source of articles of interest to TOJs).
The most frequent injury is people dropping or hitting themselves with the weights. In second are strains and sprains. The vast majority of the injuries occurred while people used free weights rather than machines.
This TOJ was disappointed to hear this because resistance training is really important to your health and well being, and weight lifting is the most productive form of it. For the past thirty years, there has been a disproportionate focus on aerobics, like running and biking, for cardio health. However, more and more studies show weight training delivers many of the same benefits and often more. Machines can be useful, but they do not develop the strength and balance that can be attained with weights, whether dumb bells, kettle bells or bar bells.
Resistance training is the only way to condition your muscles. So what's the big deal about muscles, especially if you don't plan to play NFL football? Lots. Muscles are what move you and provide shock absorption protection to your fragile joints. Plus muscles are the major site for your metabolic activity, where food is turned to energy. After training with weights, muscles continue to burn calories at a much higher rate and for a longer time than after running. For a TOJ, resistance training is especially important because once you reach your thirties, you lose about 1% of your muscle mass/year (aka sarcopenia). The good news is that you can dramatically slow this fact of aging by weight lifting.
Weight lifting poses should not be dangerous (assuming you have a healthy heart and no serious back or other skeletal issues) if you follow these simple rules:
1) Pay attention to what you are doing. Part of the benefit of a good weight workout is the concentration you put into correctly lifting the weight. Your mind can wander some when you are running on a flat road, but when you're lifting the sets are short and intense. Paying attention helps you perform the lift with proper form and stay in touch with your body. That concentration can also be wonderfully relaxing, like meditation.
2) Go slow. A weight is lifted by one muscle working against gravity to carry the weight up, then another muscle brings the weight down. If you let the weight down fast, you miss the benefit the opposing muscle receives as it comes down and risk injury due to the physics of an accelerating mass. Don't hurry to get it over with because it's a little uncomfortable. Great physical benefits accrue from that slow burn.
3) Breathe. As you lift, your energy producing system needs oxygen to provide power to the muscle. Generally you exhale as you lift and inhale as you let the weight down. I've found some lifts where I prefer to do the opposite. See what works for you. Proper breathing will ensure you observe #2 above. You don't want to go so fast that you hyperventilate or hold your breath so your oxygen drops and drops because there's no supply. Find a rhythm and pace where you can breath. Pause between sets to catch your breath.
4) Warm up 5 - 10 minutes before you lift. Swing your arms, jump lightly on your toes, rotate your knees and hips in small circles, shake your hands, swing your arms loosely from side to side as you twist your trunk. I like to finish with 2-3 minutes skipping rope or on an elliptical. Get to where you have a light sweat. Warm muscles and tendons are more flexible, and the movement lubricates your joints so they are prepared to perform with the additional friction caused by the weight.
5) Maintain good form. When you do a lift correctly, the body benefits and is not placed at risk of having too much weight placed on a weak area. You can bet that most of the sprains and strains that delivered people to the emergency room occurred when the person was no longer using proper form, not well balanced, or using another part of the body to complete the lift. Bad form = less physical benefit + more risk of injury.
6) Stop before muscle exhaustion. Some people think they need to lift until they drop. Actually, the injury zone is those last couple of dangerous repetitions when your muscles are trembling and your form is deteriorating. That's when people drop weights or strain. Stop before you get there. Weight lifting is not supposed to be punishment. Lift until you are starting to burn, but before you are on fire, grunting for breath, and pushing with other parts of your body that are not part of the lift, for example, bending your back when you are doing a bicep curl.
If you haven't lifted weights in a while, a good way to start is by just using the weight of your own body. Try sit ups, leg squats, push ups, pull ups (trying, even if you can't do one, builds strength) and burpees. This will get you used to using your muscles, feeling when you are in balance and control, and breathing correctly.
Also, it's very important to rest between weight sessions, especially if you're a TOJ. The soreness you feel a couple days after a good weight workout is caused by small muscle tears. You get stronger because the muscle heals stronger at the site of the micro-tear. Rest enables the biochemistry to get this accomplished before the muscle is challenged again. You can get tremendous benefits lifting just twice a week.
Don't believe anyone who tells you lifting weights is dangerous. They are probably selling running shoes.