Your chest muscles are important for many things (other than filling out a t-shirt). They are responsible for flexing your upper arm when you swim, moving your arm inwards when you are riding a bike, rotating your arm bone toward your body while you walk or run, and also simply breathing deeply.
So what does that mean?
1. Perform press movements from all three angles.
Instead of always doing flat bench-press or regular push-ups, include exercises on a decline or incline bench, or even with your feet or hands elevated on a ball or platform.
On a weekly basis, include incline, decline, and flat chest exercises so that you maximize your chest muscles from all angles.
2. Perform flyes of all types.
The chest exercise known as flyes really help to develop the inner pec muscles. These inner muscles aren’t targeted by presses, and there are many fun and challenging variations of the fly that you can try. Machine chest flyes, decline dumbbell flyes, flat dumbbell flyes, seated cable flyes, and standing cable flyes are all great options.
When you do flyes, make sure to stay inside your comfortable range of motion. As the weights you are using increase, it can become quite easy to injure your shoulders if you lose control of the weight.
3. Don’t forget your postural (or pulling) muscles.
When you are working on your chest, you also need to include shoulder exercises like seated rows, single arm rows, pull-downs, and pull-ups. Weak and rounded shoulders can make your chest look concave and can really mess with your posture.
Which Weights Work Best?
Free weights are believed to give you a much bigger bang for your buck because they recruit more muscle fibers. Recruiting more muscle fibers results in a greater stress response, higher secretion of muscle building hormones, and greater adaptations.
At the Eighth International Conference on Strength Training in Norway, researchers presented evidence comparing six sets of eight to ten reps of the squat versus the leg press (squat being a type of free weight exercise and leg press being the opposite), and found 50 percent higher testosterone levels and three times the growth hormone in the (free weight) squatters.
This is not to mention that the more functional movement of lifting a single heavy object with one hand tends to develop a more well-rounded physique that is also less prone to injury. Think of it this way: if you lift a dumbbell instead of using an exercise machine, more stabilizer muscles are recruited to support the prime muscles. This means that the muscles learn to fire together (and work together) because the dumbbell permits you to move through a fuller range of motion.