This year's first challenge is directed to the ones who want to loose belly fat.Start the year changing your jogging training to sprinting training because intensity is better than time spent and this way you'll loose more fat and faster, which means that your workout less boring and more effective.
So here's the challenge:
Sprint for 20 seconds and stop for 10 and then repeat as much times as you can. Try to do at least 8 repetitions.
Post your results below.