1. It is the weight that matters, not the duration
Lifting weights every day for endless hours may seem like a great achievement but it may actually be a counterproductive move towards building muscle and strength. Being able to sustain long periods of weight-lifting only means that you are not lifting heavy weights and only building muscle endurance and not strength or muscle. Do not track your strength training by the amount of time taken doing it but rather how much weight you can lift. You should aim to increase the weight. This is so as to put enough stress on the muscles to stimulate growth.