With all the variations of push-ups out there, one will help you better develop the lower portion of your chest more than others. You might feel like it's one that puts your hands on a stability ball or medicine ball, as it seems that your lower chest is on fire as you press up and down.
Variations with your hands on an unstable surface don't do much extra for your pecs, though; it's your abs and triceps you feel working in overdrive, showed a study published in a 2006 issue of Dynamic Medicine. The only version of a push-up that reliably trains your lower chest is the incline push-up, which may be a bit of a disappointment.
An incline push-up is easier than a standard push-up as the angle of your body bears some of the brunt of the weight of your body, showed research published in the Journal of Strength and Conditioning Research in 2011. If you're fit, you may find that you train the lower chest with an incline push-up, but aren't working against enough resistance to really make any substantial muscle-building or strength progress.
Degree of Inclination Matters
An incline push-up is easier than a standard or decline push-up, but how much easier depends on how high the surface off of which you are performing the exercises. A higher surface, like a kitchen counter or workout bench, will be much easier than a 4-inch step riser, for example.
If you're just starting out with push-ups and chest training, work from a high surface to a lower one to continually improve the strength of your lower chest. As you become proficient in incline push-ups, consider adding other lower chest exercises for further intensity. Decline dumbbell flyes and decline barbell or dumbbell presses are examples of lower chest exercises that can be made progressively more challenging by adding heavier weights.
Don't Dismiss the Standard Push-Up
A standard push-up also uses the lower chest, or sternal region, as the primary mover. It requires you to lift a larger percentage of your body weight — approximately 75 percent of it when you're in the bottom part of the exercise, explains the Cooper Institute.
The standard push-up gives you a chance to work against more resistance as compared to an incline push-up, but at some point, you'll still hit a plateau as your body shouldn't significantly change in weight. When you can easily bang out a set of 20 or 30 push-ups with minimal fatigue, it's time to dig deeper in your lower chest training with the aforementioned decline flyes and presses.