I decided to investigate my local authority gym tonight as by the tome I had finished work it was dark. It has a reasonable range of gym equipment nd a pool you can use on the same ticket. I haven't used a treadmill for over a year but I've been regularly managing a pace of 1km in 5'40" but to get back to my PB of last year I need to get up to 5:30/km. The treadmill was calibrated the other way round so I reckoned I needed to be doing 11/km/hr. However i really struggled to get above 10km/hr and was only really comfortable at around 9.5km. I had the slope set at 2% which didn't seem all that much. Only covered 3.5k in 25 minutes too.