This is chest superset with two exercises:
1. Barbell Bench Press
2. Dumbbell Chest Fly
This program is design to improve fast-twitch muscle development and increase muscle endurance with extended times under tension. If you want to try something challenging this routine can be what you are looking for.
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Important: The following program is not recommended if you have any problems with your joints and can be very hard if you're not choosing a weight appropriate to your fitness level. To avoid injuries, focus on the quality of the movement first, then on the quantity.