Another Race, Another PB at the Grunty Fen Half Marathon

So, two main things to report this time (and I know it’s a long time since the last one)

• My Mid-September half-marathon, with another PB and a lot of pain
• My change to an insulin pump in mid October and the quite profound change on some training habits that it’s helped with.  This is going to wait for another time as I think it’s going to be  a bit longer than I thought.

Starting with the HM, it’s quite dim in my mind now, possibly in an attempt to blot out the pain ahead of the next race, and partly just due to time and business.   The race in question is the Grunty Fen Half Marathon (http://www.elyrunners.co.uk/gruntyfen/) nice and local to me, just 5 miles to the start. This one had long been on my list of target races and this seemed like a good enough excuse.

Thinking about the build up to it, if it had not been one on my list of 5 PB attempts for the year, trying to raise money for JDRF and Highfields Friends and Parents Association (http://uk.virginmoneygiving.com/athletic_diabetic) then perhaps I would have DNS’d for the first time ever in a race.  Six weeks earlier I’d run a 40-miler with a dodgy achilles tendon (coming in 13^th) and had almost two weeks of no running afterwards, slthough my pace when I did start again was pretty good.  Luckily I was doing a job in Hull the week before – not lucky to be in Hull, but luckily my route to get there went straight past a very good sports injury specialist I know, who gave me a very good treatment and I went off again much happier.  A few short runs in the week leading up to it and I was OK to get to the start line, even if unprepared in terms of any speed training.

Now cast your mind back to September 2014, one of the hottest on record, and it didn’t let up for the day of the race and there was also a pretty stiff breeze from the west which would affect the course for about 4-5km in the second half of the race.  Maybe not ideal conditions for attempting my 1:39 race plan with a 1:43 PB, albeit one set on a mixed road/trail course without the need to test for BG every now and then.  

So, the day came anyway, I was entered, I might as well go for it and see what happens.  If I went down trying that’s no shame and a bad day at a race is better than a good day in the office anytime.  Normal race day preparations; cut basal dose right back to 0.5 units, no bolus for breakfast and rely on a few gels to keep it in the right place.  I’d planned the BG testing as well, and had trialled different distances for testing, coming down to 7km being OK without being too risky, so that would mean two tests during the race at a cost of probably 1-2mins at race pace.

BG before the start was obviously adrenaline affected as it had not come down at all post breakfast and was sat at 10.5. Anticipating a drop in the race, I took a gel which out it up to 12.2 immediately pre race. Nervously I got to the start in time to clap out the three wheelchair racers and lined up alongside my target start time. All too soon we were off.  A very quick run out and down the hill (15m high) to the bottom of the village and out onto the fen and the exposed flatlands of Cambridgeshire.  Talking advantage of the water stations I grabbed an early sponge and was rewarded with a cooling drench of water down my back.  About 2 or 3 miles in, the wheelchair racers came haring past at a rate of knots having already completed their first shorter lap of about 8km or so and out onto the longer second lap.

Number 193, "flying" off the start, elbows out in the bunch.  The guy to my left in the blue took off and I then passed hom later, blowing at the side of the road.

The first lap was relatively straightforward with not much in terms of into the wind stuff and I was pretty much on plan for pace, finding a few people to run along with for a while here and there, taking advantage of the water and sponges as I went.  First BG stop was OK, slightly higher than planned, but expecting a drop again, I took another gel.  This was also about the point at which I hit the hill (all 20m or so of it) to head back into the top end of the village again. Second time around it was going to be tough in that heat.

Second, longer lap, almost took advantage of the drinking and running club’s beer stand but though the better of it. Again, as with the first lap, the early part of this second lap was no real issue apart from the heat, with a few sections into the wind making the negative split pace plan start to look challenging. 

Another random photo JDRF vest on full display

It wasn’t until after the second BG test (again sitting around 9 or so, another gel taken) that we turned into the wind for a long stretch.  This is where it got really tough, and where I started to see the early rabbits limping along by the side of the road.  This was also where the early gains I’d made vs current PB started to get wiped out and saw me end that long into wind stretch just about on PB pace, but nowhere ahead of it.

The hill made it’s second appearance about 3km from the end and luckily this time I had a decent pacemaker to follow up it, a bloke I’d been trailing by a few metres for most of the second lap.  Now I normally have a good finish, being prepared to suffer to take a few extra seconds off my time.  This was no exception, I must have passed at least 20 people in that last few km, including the guy I’d trailled up most fo the hill.  I put in a quick spurt about ¾ of the way up, just to se if I could break his morale.  I heard him jump on the back of my heels, so put in another spurt, and another until a backwards glance showed him at least 30 yards back.  Coming into the final km I started trading places with a much younger, and evidently very fit female runner, alternately passing and then being repassed by each other until she finally made a break I couldn’t answer, but at least it spurred me on. 

Final time 1:42:58, overall position 160^th of 529, so top 30% overall and 32^nd of 63 in my age group.  But most important of all – a PB.  Time without BG testing, would have been nearer the 1:40 mark.

Pace profile below shows just how much that 4km into the wind took it out of me. I'd split this into sections with target paces for each.  You can see by the HR that I'm not taking it easy, average HR of 165 for over 90 mins is about as much as I can manage.

Split	Time	Distance	Avg Pace	Avg HR	Max HR
1	33:53.8	7	04:51	160	173
2	33:39.6	7	04:49	166	169
3	19:56.6	4	04:59	167	172
4	09:35.9	2	04:48	170	173
5	05:35.6	1.2	04:39	171	174
Summary	42:41.4	21.2	04:51	165	174

Photo of “team Highfield” a bunch of other folks also running for the school

BG at the end was up to 10.8 with the adrenaline, and spiked up to 13.8 half an hour later and then 15.5 at +60 minutes.  I resisted the urge to compensate, waiting for the inevitable fall.  Post race lunch had 15g carbs, and as I was still high at 9.0 I gave a correction there and almost overdid it, coming down to 4.3 2 hours after lunch, which really goes to show the delayed hypo potential is pretty real.

FAQs - How to low carb and still do endurance

So someone asked me about ten days ago

"Hi Dave,

I would be really interested to hear how you exercise on so few carbs, I would really like to be more active, but exercise usually equals hypos! and therefore more food, now would be a good time to mention my average daily carb intake on a non exercise day is around the 230 mark (I like my carbs). I eat pretty healthily, I cook all my dinners etc, but I really struggle to find filling low carb or no carb foods and meals, any tips you have would be really appreciated.

Thank you"

Today I finally got some time to put my thoughts down while sat on a train. Time offline can be useful after all.  Here's my answer.

As pointed out above, insulin and exercise are not the best of bedfellows (within reason). What you need to understand is what insulin does and what the non-pancreatically deranged body does in response to exercise. Essentially (and yes I'm simplifying here) insulin does three things that are relevant here

1) transport glucose to muscles
2) lay down excess glucose as fat (also prevents/limits its use)
3) suppress glycogen (prevention of liver secretion of stored glucose)

 What the normal body does in response to exercise is to significantly reduce the amount of circulating insulin. This is not a problem in terms of glucose transport into cells as you become more insulin sensitive and also there is a Glut-4 receptor which becomes more active and provides a glucose transport function.

That's the potted science bit, and next comes the more empirical/experimental bit with myself as the hamster.

Essentially you need to separate aerobic vs anaerobic exercise as the body responds differently to those, the difference essentially being the release of the stress-based or counter regulatory hormones like adrenaline and cortisol, also glycogen which are in response to stress and serve to provide that liver dump of glucose. In steady-paced aerobic exercise those hormone are absent, or almost so. The difference for me is therefore type of exercise and circumstance. Weights/strength training including yoga for me is always anaerobic; races while having a strong aerobic component as well also have the stress response; interval training is also anaerobic. These can both be characterised as stable or increasing blood sugar.

Aerobic exercise by comparison is where I can find the precipitous fall in BG if I'm not careful. This could be anything from an easy 10k to a 40 mile race (low stress with these).

Here insulin is really not your friend. You can deal with it in two ways 1) eat more carbs to compensate for the drop, or 2) reduce your insulin dosage or a combination.

Thinking about that, higher carbs diets therefore lead to higher insulin consumption which then lead to higher likelihood of problems during exercise due to residual insulin kicking around.

Things you can do

1) exercise in the morning, fasted, and even before a basal dose if you are MDI - no circulating bolus, limited basal, limited cause for BG to fall.

2) give yourself plenty of time between bolus and exercise. Novorapid is supposed to have a two-hour profile according to my consultant, but that's a load of bollock$ in my experience. Last night for example after a 1U dose for a lunch of left over Indian cauliflower, omelette and a pear, I was at 4.9 at 5:30pm, a 15g carb snack and 5km of running later I was down to 3.9. Another 10g snack and 5km later and I was down to 3.5.
I would therefore give yourself at least 2 hours before exercise, preferably 4+ and be prepared to eat. The only problem there is that this was 25g of carbs that were then preferentially used instead of fat burning.
3) reduce your insulin dose. Both Think Like a Pancreas and Pumping insulin have guides for bolus dose reduction factors, but in my case I have to be more radical than them as I have extreme insulin sensitivity with exercise (been doing it all my life and spent years on training for efficiency).

If you are going to be doing extended exercise then you can also reduce basal. At the extreme end of this for my last 40-mile race I took half a unit of levemir with breakfast of 45g carbs, saw an expected rise to around 12, then a drop back within 3 hours to nearer 7. No more insulin during the race with moderate carb intake over the next 8 hours and was relatively steady at between 5 and 7 most of the time.

So, how to do that endurance stuff on low - moderate carb. Adaptation of diet and training is the key, and it's not an overnight thing. I'd spent about two years prior to diagnosis extending my heart rate based training from cycling to running as well. This allows the creation of a massive aerobic base capable of efficient fuelling and fat burning, so that when you need it you have plenty in reserve at the top end. Reduce your intake of refined carbs. I've had one slice of bread in the entire week so far. Refined carbs are OK as part (but not all) of the fuel used in exercise but add very little nutritional value long term (think burning straw vs charcoal), so try and utilise low GI carbs where you take them. I use things like oats, veggies, fruits, seeds, beans and lentils high fibre stuff. Not too much protein as the excess is turned into glucose by the body. Don't be afraid of fats - monounsaturated fats are a great source of energy and keep you fuller longer, but you need to be aware of the calorie density. Olive oil, rapeseed oil, coconut oil are all good butter and cream are OK as well. Cheese, meat and oily fish are good, but be aware of the protein content as well.

If you really want to you can go ultra low carb, higher fat, moderate protein and try to get into nutritional ketosis (very different from DKA), at which some people have reported significant improvements in overall performance.  Some find that as I do, they need to throw in some carbs during exercise, others don’t.  For me personally I’d like to have a bash at the ketosis bit, but with my work and travel patterns this becomes quite difficult.

Take today, a quick trip to my office in London, breakfast was a two-egg mushroom omelette, no carbs, no bolus.  Lunch will be around 30g carbs with one of the M&S packaged low GI superfood salads and a few handfuls of nuts.  Dinner will be no more than 30, maybe 45g carbs.

Other good low carb breakfasts, a cup of coffee and 2-3 handfuls of nuts keeps me full until lunch, or a mix of waitrose frozen berries, sheep or goat yogurt, sprinkled with chopped nuts or flaked coconut for 15g carbs.

Dinners and lunches tend to be the most difficult with my job as it can come down to a sandwich or something with rice, pasta, potatoes etc, but you can simply leave those aside.  Dinner for example, my wife makes stir fry, I just have a big bowl of the veg and protein, no rice or noodles.

One thing that really stands out here though is the lack of education given to diabetics in both the value of exercise in managing the condition, but also inb successful methodologies.  I'm lucky in that I understood much about physiology and sporting performance before diagnosis, so I just needed to relearn my bodily responses to exercise.  Most diabetics are just given insulin and told to get on with it.



I also had the chance, while on the return journey to listen to the podcast below (downloaded to a tablet, so no phone connection charges).  It's an interview with Dr Phil Maffetone who's trained severl top class athletes and who's methods certainly warrant listening to.  I've reashed several PBs and massively improved both performance and enjoyment of running by following his methods.

http://runneracademy.com/ra060-dr-phil-maffetone-159-marathon/

What else?  HM was last week, report will follow.