When I saw this post, I thought "That's a good idea. A 30 day challenge is just what I need for the Summer holidays to keep my strength training going when I can't get to the gym as often, if at all. I'll join in with that." I posted on the comments that I would join in the challenge and then looked at the challenge ... Day 1 is OK (I've done it) - 10 push ups (yes, I can actually do 10 full push ups now after training with a personal trainer once a week for the past 6 weeks), 50 squats (easy), 15 sit ups, 5 crunches, 5 leg raises (these are a bit more difficult due to still having a weak but flexible back) and hold the plank for 10 seconds (again, easy).
However, I then looked at the last day (really shouldn't have done that!) - 75 push ups, 250 squats, 125 sit ups, 150 crunches, 65 leg raises and hold the plank fro 120 seconds (that's 2 minutes!). What!?!
OK, I'm officially mad but I'm going to give it a good go anyway.