Sometimes running is hard, or easy. Why?

Last Saturday evening I went for an amazing run with so many fantastic ingredients and yet it has thrown up a question: sometimes running is hard, or easy.  Why?

In brief the run I had was utterly fantastic and over a course which I have run many times before.  It was an 8.5 mile hilly run going from Dunstable to Church End, through some footpaths and across Whipsnade Common.  Then passed Dell Farm and out on to the Downs.  From there is was a fast run along the escarpment (highlight enjoying those inspirational views) and then back down into Dunstable.  My moving time was 1 hour 14 minutes and I gained about 780 feet in elevation.

With this run, the further I went the easier it seemed to go and the last 3 miles were well under an 8 minute mile.  Everything was simply coming together so well and I knew my running form was good.    I should say it was at dusk, having set out at about 8:45pm and the weather was pleasantly warm but not hot.  The air was still and an ideal summer evening.

And yet I have done this run many times before over the last 8 years of running.  Sometimes I have found it hard going.  Furthermore I have found some runs after work to be particularly hard going, even simply a 3 mile jog lasting 30 minutes.  Sometimes my legs have felt like lead and I've been stiff with little energy.  What an amazing contrast to this other evening when I felt so alive, full of energy, supple and brimming with excitement.

It could simply be a case of "that's the way it is".  Other possible factors could include how well hydrated I am, nutrition inside me, blood sugar levels etc.  And then there is the mental, thought-based side.  What are my expectations?  How eager am I?  Have I missed running over the last couple of days?  All of these possible factors can make a difference in my view and I think these all add to the variety of running.

If every run was in perfect conditions, over the same route with the same performance it would soon be boring, just like treadmill running can be.  So thankfully we are not like that at all, we should thrive on variety and take the good with the not-so-good.  Even though I am naturally optimistic and "half full" in my approach, I need to remind myself of these things sometimes!