Dr Niall Moyna of DCU was speaking to Joe Molloy on Off The Ball on Wednesday evening, and he was talking about the fitness tests that you can take at home to check where you are in terms of your fitness.

They were based on four key aspects: ideal body composition, cardiovascular fitness, balance and muscular strength.

But an interesting part of his discussion was when they talked about the issue of keeping teenagers fit - and how difficult it can be.

Joe joined Kieran on Thursday's edition of The Hard Shoulder, along with Catherine Woods, who is Chair of Physical Activity for Health in the Department of Physical Education and Sport Sciences in the University of Limerick, to discuss how we can keep children, especially girls, physically active.