I suffered a severe rib cage injury in 2010 during the first year of my personal training journey. The injury forced me to start searching for recovery, and eventually, I did found the way to fix the sternum pain from dips.

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I experienced the sternum injury during the weighted parallel bar dips. Parallel bar dips are the most common way people injure their sternum. My biggest mistake was when I didn't stop the workout the moment I was injured. I was doing the 3 set of my weighted dips and I still had 2 sets to be done. I tried to do the next set and I injured my rib cage and sternum even further.

Injury prevention principle: In the case of injury, stop the exercise when it hurts, not when the sets and reps are done.

My rib cage was injured for over 6 months. I tried pretty much everything. I visited a nurse, a physiotherapist and then finally, I visited a physiatrist. Did anything help? No, absolutely not. I didn't experience pain during my daily life activities but I still couldn't do dips or planche work without feeling severe pain in my sternum. When I was meeting my physiotherapist and my physiatrist, I was given numerous of rib cage mobility exercises, which were designed for grandmothers to be able to cope with their daily life without pain and discomfort. The standard mobility rib cage exercises just weren't effective enough to build strength and mobility in the rib cage for me to be able to perform dips. In order to build real mobility, the mobility exercises have to be strenuous enough to cause the growth and expansion of your rib cage. I had to find my own way and I did find the way to fix the sternum pain from dips. Here it is: How To Fix Rib Cage Pain From Dips

First and foremost, stop doing the exercises that cause pain! They aren't helping, in fact, they are hindering your recovery. If you feel pain in your sternum while doing dips, don't do dips. Then, after you have stopped doing the exercises that cause pain, you need to build flexibility and mobility in your rib cage and serratus anterior. And do it in an effective manner. This exercise pretty much saved me from sternum pain and significantly increased my rib cage mobility: Leaning rib cage stretch for rib cage flexibility

You can do this exercise against a table or a wall. Both work extremely well; but a table or a box offer the most freedom of movement for this exercise. If your rib cage is tight, you will definitely feel it in your sternum. If your rib cage isn't in a bad shape, you will feel it in your serratus anterior instead. Increasing the strength and mobility of your serratus anterior muscle is the key here. Serratus anterior protects your rib cage from resistance. Serratus anterior, also known as the boxer's muscle, is involved in shoulder abduction, elevation and upward rotation. If your serratus anteriors are too weak, your shoulder girdle cannot sufficiently hold your bodyweight. This causes the pain in your sternum and rib cage. In other words, your skeletal structure is holding your bodyweight - not your muscles. The leaning rib cage stretch above will improve your serratus anterior flexibility to a great extent. The leaning rib cage stretch will improve the flexibility, but not will do enough for the strength of the sternum. To build strength in your rib cage and sternum, this exercise will save the day: Straight-arm dumbbell pullover for rib cage mobility

Pullovers have been known as the "rib cage expanders" since the beginning of 20th century. The old school lifters and bodybuilders swore this exercise increased the size of their rib cage. Nowadays, many people dismiss the pullover exercise as a rib cage expander. Straight-arm dumbbell pullover may not increase physically the size your rib cage, but it will definitely increase the flexibility, mobility and strength in your rib cage and serratus anterior. The key is to focus on maximal range of motion at the bottom of the exercise. If your shoulder flexibility is not good enough, you can begin with bent-arm pullovers. The better you will be able to straighten your arms, the more the exercise will stretch your rib cage. Bent-arm barbell pullovers for serratus anterior strength

Bent-arm dumbbell/barbell pullovers will build the strength and mobility in your serratus anterior and rib cage . Serratus anterior strength will protect your body from the sternum pain in dips. If you do these every day (start light), you can make real progress in just 4 weeks and notice how your dipping performance is improving along with it. Even if sternum pain is not a problem, but you experience tightness in the rib cage with dips or other exercises, or you start to experience some sternum pain when you do really heavy weighted dips or ring dips, these exercises should solve these problems and take you to the road of recovery. In addition to these exercises, one of the keys is to effectively strengthen your serratus anterior. If these exercises won't help, you can try:

Dumbbell shrugs with upward rotation.

Serratus anterior push ups, also known as scapula push ups.

Straight-arm dumbbell shoulder abductions for serratus strength.