Since completing Salisbury 54321 50k last Sunday I have been thinking about my endocrine system and how my ultra training has affected it. For those of you who don’t know, simply put, the endocrine system is essentially a collection of glands that release hormones and regulate your metabolism/body temp etc. When your body comes under stress (physical or mental) your endocrine system responds to help maintain a balance. I am sure that many of you have heard of cortisol? This is one of the key chemicals involved.

Although I am fairly new to running and the ultra world, I do know a lot about the endocrine system – it’s an area I lecture in. I am sure that many of you know that to train for an ultra marathon you think about your muscles and as part of your training you do a regular long run in order to stress and train those muscles.

But how many of you think about training your endocrine system for an endurance event?

To train for an ultra marathon (anything over 6 hours duration) you stress and adapt your muscles but you also stress and adapt your endocrine system. The latter being particulary important for ultra running. You could probably run a 50K with minimal long training runs but in order to complete a 50K with reduced negative endocrine effects, you need to train that endocrine system! This takes time and it has been reported that is can take a few years (I have not verified this claim).

So how does all this relate to my Salisbury experience?

Well my aim for this race was to complete it feeling as if I could have run more……I nailed it. But it was the week that followed that interested me more. It has been 5 days since the race and by listening to my body carefully, I have noticed a significant change to my body response following this 50K. It is this point that makes me believe my endocrine system is adapting well to endurance running. I have done 3 runs these last 5 days: hills, progression and easy and I was able to put in the required effort without it feeling tougher than normal.

Following my 1st 50K event, my muscles felt fine but when I attempted to run, it felt hard – but not because my legs were suffering. I believe my endocrine system had been overloaded for this event and was trying to reach a balance and it wasn’t quite managing it.

Now, I believe my endocrine system has adapted and as such I am in a better position to complete my upcoming 50 mile event.

The key point I want to make is, although you could complete an endurance event on lower mileage I do believe that in order to successfully complete such an event, you have to train your endocrine system as well – and this takes time.