Very cool! Back in January I started the
30-day Plank Challenge. I have not been consistent in doing these every day but I have noticed a difference in that I stand straighter and my back no longer hurts after standing for more than 15 minutes. I continue to do these and I am managing to increase my times but not to the schedule outlined in the link, but what I am able to do has been making me stronger. I did heft a 50+-lb. laser printer from a hand truck into the backseat of my 4x4 without hurting my back, after about three weeks of planking.
I have not done the “challenge” either, however, do some Planks regularly....it IS amazing how much it challenges your whole body....got to 2 minutes the last time....and I’m 62!!