Bodybuilding programs are typically split up to hit each individual body part once a week. That means you go a long time between workouts for a particular muscle group. If you can only lift weights three times per week, try switching to full-body workouts where you work the entire body in each session. This way, you’ll hit each muscle three times per week. Perform two to three sets per muscle group.
If you’re training four days per week, try an upper/lower split where you’re hitting each muscle twice a week with about five sets each. Increasing the frequency with which you’re working each muscle will allow you to achieve strength and muscle gains more rapidly. The key is to keep the volume low to moderate to avoid overtraining.