This is Bart Yasso.

As well as being a running legend (apparently) and looking rather cool (definitely) he created a workout that, many claim, predicts your marathon time. 

The idea being that if you want to run a 4.00 marathon, do 10 x 800m in 4.00 with an jogging recovery of 4.00. Want to run a 3.30 marathon? Complete 10 x 800m in 3.30 with a 3.30 active recovery.

Bart recommends incorporating these Yasso 800s (that’s what the training is called) into your regular marathon training. He also suggests starting with 4 x 800m and working your way up to 10.

Tonight’s session was a bit of Yasso training. Before Christmas I was up to 6 x 800m, but after a couple of weeks of very little speed work, I dropped tonight’s Yassos down to 5 x 800m – don’t forget I’m also running every day – don’t want to go crazy. Ended up doing 4.3 miles in all – the Yassos session is a hard session – not looking forward to doing 10 of ’em. 

Total Janathon mileage = 34.8