Is it usual for your 5K pace to get slower when training for 10K?

[Saruma]

Am currently training for a 10k in 3 weeks time - this week I covered 9k in a fraction over one hour (interval running). I have recently slotted in a couple of 5K's, just to give my limbs a rest from the longer runs. To be honest, I expected to breeze though the runs but am bit shocked to find I'm a good couple of minutes off the 5K pace I was covering in March, before I started extending my distance. Is this common, or have I done something very wrong in my training? Starting to think I haven't mixed things up enough!

[Oldgirl Graduate]

I would think it is quite normal. If you think back to your 9 weeks of C25K as you got onto the longer times what was everyones advice to those people who didn't think they could manage. "Slow and steady" So your time for 9K is very good and once you get to the magic 10K you can then start to skim off some time. You will then be more prepared to adjust your timings for shorter runs too, some short fast runs will help that 5K faster time come back to you. Wish you luck for your 10K

[MaryAB Graduate]

My 5k time is a bit slower since I started doing 10k's but only by a minute or so. I've done quite a few 10k runs and the second 5k is normally a bit faster than the first half! When I get tired though I always tell myself that the quicker I run the quicker it will be over!

Interval training and hill sprints are good for getting your average speed up x