The words "strength training" probably make you think of several images; like the bench press, squats, deadlifts, pull-ups, or whatever. Many people don't strength train because they may feel like they just don't know how. Maybe they don't have the energy to learn or maybe they are just intimidated by the images strength training conjures up.
Strength training is good for you. Everyone could stand to be a little stronger, or at least strong. Strength training does not have to happen in a gym though. Strength training does not have to involve dumbbells, kettlebells, barbells, or any kind of traditional strength training equipment. A person can strength train simply by learning how to move their own body. Simple things like crawling, climbing, jumping, running and playing can make a person extremely strong. Yes, just moving your body the way it was intended to move can make you strong and healthy.
If you are doubtful of this, you should try it. At the very least, you will start to move and feel better. At the most, you will build strength. Take the pushup for example, why would a person bother with the bench press when they can't even do a good looking pushup? A pushup can make you strong! A bench press can give you the illusion of strong. Or, take the body weight squat - it is good! Why would a person put a bar on their back and do squats when they can't even do a good looking bodyweight squat? Learning how to move your body can really lay a great foundation for strength.
Not only that, you can actually become freakishly strong by just learning how to use and move your body. Don't believe me? Here is a one legged, one arm pushup. It takes strength to do this, and it took learning how to move my body to get the strength to do this. All the weight lifting I've done in my life, never gave me the strength to do this:
Learn how to move your body! It is great strength training!