If you've ever wondered (mid-crunch, most likely) exactly how many sit ups you should be doing every day to optimise your fitness, then you're in the right place - this is exactly the type of question ...

When you buy through links on our articles, Future and its syndication partners may earn a commission. Credit: Getty Images Bored of planks and crunches? Why not try mixing things up with a killer ab ...

Experts have revealed how many sit-ups you should ideally manage at your age — and the numbers may surprise you. The post How ...