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A few years ago, XNRG's Head Coach Andy Mouncey decided that the only way to get to the bottom of the High Fat-Low Carb debate was to experience it directly.

He committed to a strict 14 day diet reset without carbs or sugars, as advocated by as a first step to making some lifestyle changes that he would stick with and monitor over the next couple of years. Here’s his account of days two to nine...


Day Two: The Adjustment Bureau

5.15am and I’m supposed to eat within an hour of getting up, so it’s almonds and cheese with the usual water and tea before heading off to a pre-breakfast Crossfit. I put the slow cooker on for the usual porridge to be ready when the rest of the family get up in a couple of hours, with a forlorn note that it’s ‘just for you 3’ (sigh). I really love my porridge…

Wobbles post-Crossfit back home while cooking my breakfast omelette has me grabbing another egg, more cheese and chorizo. Charlotte (Mrs Mouncey) stands well back as I go momentarily tunnel vision:

‘Er, is this supposed to happen?’

Well, I figure there’s going to be a kick at some point and I had expected it to be after a high-intensity Crossfit session.

‘You may need to reduce your training during the Two Week Test’ advised Dr Phil.

Makes sense, but I’m retaining my two sessions a week and these will be the only high heart rate sessions among the fat burning steady state stuff. So if there’s going to be an initial challenge while my system settles in it’s likely to be here.

Food stuff today:

Cream in coffee (and omelette)

Cream cheese on celery

Cheese, almonds, chorizo, baby tomatoes, avocadoes, olives - these combos keep me sane during the day

Homemade soup for lunch

12 more days of this? I can see me running short of food ideas…

‘Gonna need to go shopping again…’ (I can see me getting through the veg stuff like no tomorrow) ‘and some more food ideas quicker than I thought, ‘ I said to Mrs Mouncey.

‘Veggie curry this weekend then, luv?’ replies my saviour Thinking Clearly Under Pressure.

And suddenly Saturday and Sunday didn’t seem quite as scary.

Friday night still looms though, and Friday night is traditionally beer and crisps night in our house – a ritual that has latterly expanded to include the boys (with a soft drink version) in the first part of quality Mummy and Daddy Time.

Beer and red wine is off for me though – whisky and dry white is on – but the crisp substitute has proved more elusive so far.

‘Almonds and carrot sticks for you then,' says a grinning Mrs M.


Day Three: It’s The Rituals Wot Dun It

Another sobering low HR outing this time as a couple of hours astride my trusty steed. It’s granny gear city after which I prowl about at home scoffing tomato, cheese and carrot while wrestling with the urge to snaffle sugars and carbs.

Six Nations rugby on the telly brings its own challenge – rare quality TV-time with gallons of tea and…

Er, biscuits.

Christ – no biscuits! But what am I gonna have with my tea then?

Belatedly I realize how much of my food is based on ritual not need:

Rugby-TV-Trained In The Morning; Tea & Biscuits On The Sofa With My Lady In The Afternoon.

(It’s the same with mint imperial sweets in the car: I’m driving therefore it’s time for a mint. Yesterday I reached as usual for the bag and Charlotte just looked at me:

‘What are you doing?’

‘I’m having a mint – want one?’

‘But they’re pure sugar!’

‘But they’re just a mint – oh…’

Flippin’ eck!)

In the end I go for the distraction strategy and drink even more tea than usual even faster than usual.

And then wee.

We have a Council Of War in the evening ‘cos it’s obvious my initial menu planning will require considerably more variety then I’ve given it otherwise I’ll go mad. In my head I’m running a big future-pacing strategy: Tomorrow is Day Four and that then means nine days to go – and THAT means I’m down to single figures!

Day Four: Man Up

I’ve never been so pleased to see beetroot, spring greens, mushrooms, tomato and cheese on a plate, but the colour and variety makes me smile like a kid with a big chocolatey ice cream.

Later in the day I realize where the resolution is coming from: After 5 years of uncharacteristic off-on, half-hearted and unfinished stuff on a scale never previously amassed, I really bloody need to feel good about giving something 100% and finishing.

Day Seven: Mr Grumpy Chops

According to the forum I should be skipping by now and all my aliments miraculously disappear.

Or so at least part of me has chosen to believe.

The reality is that I feel flat and somewhat less than inspired by the limited food choices of my test period. This morning’s early morning ride has done nothing to lift the mood. Groveling on granny gears again – that’s 39/32 gearing to crawl up what feels like the slightest rise – I pulled to a halt 40 minutes in with a serious wobbly lip moment.

Watching the sun come up only marginally lifted the mood, but as the prospect of returning home and having to explain my unexpected presence with a pathetic ‘I felt crap’ was even worse, I gritted my teeth and stayed out for half the allotted four hours.

I just can’t summon the energy or motivation for the full whack but two lots of two is an achievable prospect, just.

Plan B then.

Later that morning Charlotte and I share a coffee and the self-indulgent ‘woe-is-me’ wallow comes right out. As the garbage comes out of my mouth I know what’s coming even as the words are forming.

There’s a pause as Charlotte clearly decides to moderate her instinctive retort – but her reply still cuts me off at the knees as well it should:

We had a family funeral two days ago and if that wasn’t bad enough attending that was her best friend from school recently diagnosed with cancer and clearly going through all sorts of hell.

Oh you self-centred, selfish f***ing pathetic b******, Mounce…


Later that day I’m quietly proud to stay out for 3 hours. It’s not pretty and it’s tortoise slow but it’s a commitment made good and I’ll take that.

Researching some more that evening I find some perspective and reassurance:

  1. While there are a lot of people who have a transformational first few days and feel great, there are also those who don’t.
  2. I’m eating less carbs and even though my training intensity is dialed back I am still doing stuff.
  3. My increased tiredness and crawling pace is due to reduced carbs not a plunge in fitness – which is why for athletes this test should really be done during the off season or at the start of a training block.
  4. I’ve just thrown what might be a monumental change at my body – and my system is probably still doing WTF??
  5. And what might be the clincher…If I’m already eating close to optimum – and I’m not 100% clear about this but the last 2 years I have got to grips with my nutrition much more than I ever have, and I do have decades of aerobic training behind me  – then a TWT will throw the body out of kilter even more.

Lost in the noise of the TWT but grinning out from the page of my diary as I review is the evidence that a couple of days ago I ran easy on two consecutive days without a whisper of complaint from my foot.

Well, whaddaya know…

Once more I end the day with cheese and almonds, and turn in a still chastened but considerably happier husband.

Day Nine: A Corner Turned?

A hike-jog over the fields yesterday as the sun came up had me smiling as I realized how long it had be since I’d been able to trot pain-free round my local paths enjoying the early morning sights and sounds. I also now genuinely look forward to my breakfast omelette – not least because the quality and variety I can produce has dramatically improved over a few short days.

That’s leverage for you, then.

We’ve also now found a way of integrating Daddy’s Experiment Breakfasts into the normal breakfast choices and routine of the family with a minimum of fuss.

The fact that I can now accept a slow-cooker full of porridge on the table infront of me without wanting to dive in has helped this immeasurably.

So tomorrow is Day 10 which means then it’s only four days to go…

The only fly in the ointment is a problematic left quad that is now sore and painful for the third time in about four to five months. The pattern has been: Ramp up the training – left quad breaks – fix it – repeat. Despite all my DIY rehab efforts I can’t seem to reach the root of what appears to be a soft-tissue problem. Conspiracy Theory #1 is that my foot problems – yes, same side – have made me move the leg in a different way and the muscles are struggling to adjust.

I’ve done my best to track cause-effect and to try see/feel what happening on this side but I ain’t clear yet. But there’s clearly a problem that’s not healing enough to withstand the workload. So maybe I need to go back to basics with this as well:

Rest-Ice-Compression-Elevation intensively for a few days and if that doesn’t work then I can waste/spend time and money chasing the conspiracy theory.


Anyway, I’m pretty sure Charlotte thought I’d bin this TWT days ago but as no cracks of note had appeared by halfway (and the early wailing was just for show) she figured I really HAD decided and so has started her own adjustment. We don’t have a lid on it all though quite yet:

‘Hey, we could go out for a drink tonight!’ (Grandma is here later which means we get a pass out).

‘Yeah! We could – oh.

Beer’s off-plan’ (big sigh).

It’s dry white wine or whisky if I want a rock n’roll Friday.

We settle for hot toddy in a flask and go walk up a mountain.


Andy is XNRG's head coach, a published author and one of the leading thinkers on high performance.

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