The complete strength training guide for beginners. Strength training is a method of training that helps you increase your muscular strength and build muscle mass and can use many different types of training. Strength training, also called weight training or resistance training, is an important part of any fitness routine. It helps make you stronger and also builds muscle endurance. Develop total-body strength and build maximum muscle mass with a simple set of dumbbells, a barbell or a kettlebell.