GOOD MORNING!!! As promised here is another plank exercise that will help strengthen your core and also work on your shoulders at the same time. You can do each arm individually or alternate. I personally do alternating arms and count 1 rep after I have completed the up/up down/down on both sides. Repeat and do 10-12 on each side or 20-24 total.
These are a killer but it works!! They are kinda like Plank Push ups
Enjoy! Let me know what you think of these and how many you can do.