Strength training is a great way to improve performance and, more importantly, reduce your chance of injuries. Endurance training gives you a strong heart and lungs but doesn't protect you from injury the way strength training can.
For most cyclists, strength training is like another language, and it can be intimidating to venture into foreign territory at the gym. It doesn't have to be that hard or complicated, though. Adding strength training to your routine one or two days a week can make your body more resilient to injuries, improve body composition and it can increase your confidence.