Marc Keys has been busy uploading tons of tutorials to his Speed Power Fitness YouTube channel.
Today he adds a twist to the GHD Sit Up.
In this diabolic variation your buddy holds a stick and you move your body in a circular motion around it.
You know how some exercises have a country name in them? That’s why from now on these shall be called Irish Twists.
Of course, you can do the same circular motion with back extensions.
Also check out his Push Press Tutorial here.