This is a 4-day per week workout plan designed for ectomorph body types who are looking to gain muscle mass. The plan focuses on full-body exercises that use dumbbells, allowing for a comprehensive workout without the need for barbells or kettlebells. Each day is structured with a warm-up that includes light cardio and dynamic stretching to prepare the body for the workout. The workouts include exercises targeting the upper body push, lower body pull, and full body. The exercises are designed to target various muscle groups, allowing for a well-rounded workout routine. The progressive overload principle is applied, meaning the weight used in each exercise should be gradually increased each week to stimulate muscle growth. After the workout, a series of stretches are recommended to help improve flexibility and reduce muscle soreness. The cool-down includes light cardio and static stretching to help the body recover and prepare for the next workout. This plan is a great option for ectomorphs who are looking to gain muscle mass in a gym setting and want a comprehensive workout that utilizes dumbbells. It's important to listen to your body and make adjustments as necessary and always aim to increase the weight used in each exercise.