Here is another challenge for you to tryout.

This time you will be working your chest and back.
Some people disagree on working two main muscles back to back.
But for me I always get great results and a major pump. Also antagonist/ agonist
training ensures that you keep good muscular balance.
Doing this challenge will get your heart pumping and tire you out fast, but that is the
whole point of the challenge, to see if you got the stamina to do it within 15 minute.

Here is how it goes.

Rack up a barbell with weights, go light at first because you will be doing high reps.
If you are doing this in a gym get a rack that has a pull-up bar.

1st set 20 bench press,15 pull-ups
2nd set 15 bench press,12 pull-ups
3rd set 10 bench press, 8 pull-ups
4th set 5 bench press, 5 pull-ups

Keep good form and don’t cheat with the pull-ups and presses.
When doing the pull-ups make sure you go all the way down, when pulling up
make sure your chin gets up to the bar. Same with the bench press, all the
way down, don’t let the bar touch your chest, then all the way up.

You will be doing a lot of reps. So if you need to take a break, then by
all means take a break.
Also after you do a set try to take a good minute or so to recover.
Just remember that you only have 15 minutes to finish.

Try it you just might like it!!