Training on a low-carb diet

[valkyrie]

I wasn't on the bike for the whole of September, as I was mostly on holiday in France, riding my motorbike and eating and drinking far too much. When I came home from that I went to Munich for a few days with work, which meant eating lots of pork and drinking lots of beer. Then I got a cold.

Cos of all the extra beef put on over the month I've been on a low-carb diet for the last 3 weeks (it's the only kind of diet that I lose weight on). Did a 200km audax a week ago and my heart rate was way too high and I felt like shit. Just done a turbo-trainer session tonight and my heart rate is still 20bpm higher than it should be for the routine I did. It's also taking an age to come back down. When my heart was doing this a week ago I put it down to the cold, but I've basically felt OK all week so I think I'm over that. So the very long-winded question is - does being on a low-carb diet significantly impact on exercise performance?

[Chris S]

In short, yes - you should be on a balanced diet. I tried low-carb for a while. It was miserable, though I did lose some weight.

But it just sounds like you are out of condition - which may or may not be down to diet. Doing nothing much except holidaying and boozing, then eating pork and drinking beer, and then riding a 200? Just what did you expect?

[GruB]

Welcome to my world 
Low carb is fine.  Eat less more often.
I agree that it sounds like you are out of condition more so than suffering due to your diet.
It does take a while to get your body used to fewer carbs though.

[Chris S]

I'm interested Grub.

What proportion of your "low carb" dient is carb?

Aren't you more interested in GI than carb per se?

[valkyrie]

I agree I'd expect to be slightly out of condition after my time off the bike, but nothing like how I'm performing now. I use a Tacx iMagic trainer so I've got 2 year's worth of data on my performance on the same routine and my heart rate has never been anywhere near this high for the same power output. My options are -

1. If I'm out of condition - train harder and more often
2. If I've still got a virus - do very little training and wait to get better
3. If it's 'cos of the diet - just accept it until I'm down to target wait, probably just do fat-burning rather than higher power routines

If the view of the panel is the 3. isn't really a possibility then I'm down to choosing between 1. and 2.

[GruB]

Cut sugar out, totally.
Only buy no added sugar items.
Sugar in fruit is better, but you cannot have too much.  No more than 2 apples a day and one banana for instance.

Bread other than home made wholemeal is off the menu.  Current bread is processed to such an extent that it has a high carb value in that your body converts it to sugar / glycogen very easily and quickly.

My current diet is low in carbs and also low in calories. I am using more calories than I am taking in.  I am losing weight, gradually.  This can only go on to a point then my body would start to break down muscles once the stored energy is depleted / fat in other words.

I do not have to measure / weigh my food.  Mrs G has had 13 years of me being diabetic but only since March and my little falling of thy wagon, do I have to take more care.

[GruB]

V,
It is hard to tell.  You are the best judge of your body / fitness.  Having previous data to compare with is valuable too.
Perhaps you have not recovered sufficiently from the virus and that combined with the low carb diet is making your heart work harder to keep you fuelled.

Are you eating just before you train?  I notice that when I cycle after eating my HR goes up by approx 5 %.  I think my body is trying to digest the food but also maintain what I am asking from it power wise.

[Manotea]

Maybe its getting old(er) but I really notice the affect of the changing of the seasons nowadays. Exercise on a (relatively) low carb diet is strictly a warm weather activity I reckon. In the winter you need some carbs to keep warm. The cold will take care of any extra calories.

From Manotea's Little Black Book of Hard Core Homilies:

#5 Winter is your friend.

#6 If you feel cold, eat more and work harder

[GruB]

Manotea,
Winter is indeed your friend.
If you can't eat extra carbs, you can compensate by purchasing more and more high quality kit from Assos 

[Greenbank]

Manotea, lots of carbs required if you're joining me on my next DIY 200.

Over the North Downs to Royal Tunbridge Wells, Ditchling, back over the lumps to Horsham and then, hopefully, back via Leith Hill, White Down, Ranmore Common, Box Hill and Epsom. Bikehike reckons about the same amount of climbing as the Anfractuous. Should be lovely on fixed.

Feel free to quote this back to me at various points on the ride...

[Manotea]

Manotea,
Winter is indeed your friend.
If you can't eat extra carbs, you can compensate by purchasing more and more high quality kit from Assos  

Yup, almost time to breakout my Airjack!

Over the North Downs to Royal Tunbridge Wells, Ditchling, back over the lumps to Horsham and then, hopefully, back via Leith Hill, White Down, Ranmore Common, Box Hill and Epsom.

Ditchling and White Down. Both as yet unconquered!

[mattc]

Cut sugar out, totally.
Only buy no added sugar items.
Sugar in fruit is better, but you cannot have too much.  No more than 2 apples a day and one banana for instance.
...

I don't think that is what most people mean by a "low-carb diet".
V can confirm, but usually this means a diet with fat and protein in abundance (well, not too much, or you wouldn't lose any weight!).

PERSONALLY I would expect a diet like that to reduce your performance, although only in the upper reaches - once you're used to it, steady long-distance pace might not be affected at all.

[cometworm]

It's worth reading "the Paleo Diet for Athletes" if you want to combine low-carb eating with endurance training. I can't vouch for the science behind Cordain's ideas, but Joe Friel co-wrote the book so it has cycling-cred ...

[mattc]

I must read that one day - I have glanced through a copy.

I think the emphasis is on avoiding processed foods - hence high GI stuff, white bread etc, and avoiding additives (like too much salt/sugar). But I know I'm simplifying!

[valkyrie]

I've been cutting out all carbs as much as possible - down to about 70grammes a day is the target, as there are some carbs in practically everything. In a nutshell the main diet rules are - no sugar, no cereals, no potatos, no pasta, no milk, very little fruit. I'm eating lots of fish, meat, cheese, salad, vegetables. It's an easy diet to keep to, only real problem I've got is with business meetings with sandwich buffet lunches. And I'm not allowed beer . Anyway, I lose weight on this and not on any other diet I've tried.

Back to the training/performance issue. I went back on the turbo tonight, did the same routine, average HR 15bpm lower than it was on Monday, so I'm now happy that it was the virus lingering on and I'm finally shifting it.

Thanks to all for your opinions!

[GruB]

That is the diet of a diabetic