A quick update on my quest to become a fat burning beast!

So, I have been eating a paleo / primal diet for just over 2 months now.

As I mentioned in my previous post, I have found the transition to a low carb diet really easy and I am someone who has always eaten a lot of carbs and sugary snacks.

Mark Sisson says that a good way to test if you have become a fat burner (also known as fat adapted), it whether you can skip a meal without feeling feint, ratty or any other symptoms you would usually associate with missing a meal. Previously, I would have struggled going even a few hours without a meal or a snack and my wife could always tell when I was heading for a sugar low because I would become really short and snappy! I am now at a point where I can comfortably go for 6 hours without feeling the need to eat. Often, that window will have included some exercise.

When I adopted this way of living I felt that the challenge was always going to come when I wanted to teach my body to burn fat (rather than carbs / sugar) during my long runs. I feel I am well on my way to becoming fat adapted and I have been able to run for over an hour and a half without any fuel (and even in a fasted state). This is running at my sub-aerobic threshold of less than 135 BPM (or 75% of my max heat rate). The trouble is, currently this equates to roughly 9:30 minute miles. My target mile pace for Chester Marathon is 8:00 minutes per mile. As you can see, I have some work to do in order to be at 75% of my max HR whilst running at 8:00 minute pace!

Having run an easy 10k on Saturday, I tried for a fasted 9 mile effort at marathon pace on Sunday. I don't mind admitting that I found this harder than expected and simply wasn't able to hold the pace in the final few miles. It is all well and good being able to go for 6 hours without needing to eat but I need to ensure that I have enough fuel for my runs, so this was a good lesson in this regard.

I have faith in my training plan (which starts on 17th June). I used the same plan for Berlin last year and I remember how my fitness improved on those longer, marathon paced efforts. Of course, I was a sugar burner last year, so it will be interesting to see how my body copes with those longer training runs this time around. Watch this space!