Insulin Resistance

[Seeking Motivation]

A question the scientific types among you:

The articles I’ve read about prediabetes and type 2 diabetes say that high blood sugars after meals are mostly due to the body becoming insulin resistant. Ie. producing more insulin in order to absorb the glucose floating around your blood, getting used to these higher levels, thus increasing insulin resistance and creating a sort of vicious cycle.

So what I’d like to know is, if one eats carbs fairly soon BEFORE exercising, will the very nature of the way that muscles use glucose for fuel take a good quantity of that glucose out of ones system before a larger than ideal insulin release occurs, or do you need to fuel yourself with less carbs and more protein to avoid as much total insulin being released?

The way I understand it is that insulin acts as a key to utilize glucose for energy, so basically I just want to know that one is not negating the blood sugar lowering benefit derived from exercise by flooding your system with excess insulin in order to process and use it, thus increasing insulin resistance?

Long post. Sorry. Hope it makes sense?

 

[Northerner]

Hi, welcome to the forum 🙂 You are right that insulin acts as a 'key' to unlock cells'ability to process glucose for energy. The problem with insulin resistance is that these 'keys' do not fit in many of the 'locks' on the cells. The locks are called insulin receptors, and exercise has the effect of increasing the number of these receptors that form on the cells, increasing their ability to accept glucose. Without exercise, the number of receptors does not increase, glucose will build up in the blood triggering the pancreas to produce more insulin to try and overcome the effect. However, since the cells cannot use this insulin, the body instead uses the glucose and the insulin to form fat cells, which may in turn increase insulin resistance - as you suggest, a vicious circle.

What needs to be achieved, ideally, is to consume the amount of carbs that can be tolerated i.e. not cause too great an increase in blood glucose levels, which will then be easier for the non-damaged cell receptors to deal with, plus exercise which will allow the insulin to be used more efficiently and completely. So, don't overburden the system with too much carb, and exercise after eating to increase sensitivity. Regular exercise will increase the body's cell receptors to improve blood glucose control for many hours after the actual exercise.

Hope that makes sense! 🙂

 

[Seeking Motivation]

Thanks for that excellent and concise reply. That gives me a much better idea as to the mechanics of it all.

So just to confirm, the way I understand it then is like this:

I consume a breakfast of say 50g carbs and have a level of 10mmol after 1 hour without exercise.

I eat the same breakfast the next day but walk for 1/2 hour straight afterwards and get a level of 6.5 after 1 hour.

Although the exercise on the second day has served to increase the number of receptors on my muscles which store glucose (good), I've still subjected my body to a level of carbs that will have released the same amount of insulin as on day 1, when I didn't exercise (bad)

Is that right?

In that case, all things being equal, are my levels lower after exercise due to my muscles taking up the glucose in my blood or are they lower because my body is overcompensating and producing more insulin?

 

[Northerner]

Thanks for that excellent and concise reply. That gives me a much better idea as to the mechanics of it all.

So just to confirm, the way I understand it then is like this:

I consume a breakfast of say 50g carbs and have a level of 10mmol after 1 hour without exercise.

I eat the same breakfast the next day but walk for 1/2 hour straight afterwards and get a level of 6.5 after 1 hour.

Although the exercise on the second day has served to increase the number of receptors on my muscles which store glucose (good), I've still subjected my body to a level of carbs that will have released the same amount of insulin as on day 1, when I didn't exercise (bad)

Is that right?

In that case, all things being equal, are my levels lower after exercise due to my muscles taking up the glucose in my blood or are they lower because my body is overcompensating and producing more insulin?

What is happening with exercise is two-fold:

1) You are using up some of the energy provided by the carbs when you exercise, and this is happening more efficiently because your cells are more receptive. Thus, your blood levels fall.
2) Your body will recognise that your blood glucose levels are falling back to normal, so will produce less insulin, as less is needed to keep your levels in normal range.

Without the exercise your levels remain higher and thus your pancreas produces more insulin to try and compensate and bring them down.

 

[Seeking Motivation]

Got it.

So is it true to say that there is no problem with me eating an amount of carbs that normally raises my blood sugar fairly high, IF I time it so that I burn that glucose off with exercise before the levels are allowed to get too high. This will then avoid my pancreas kicking in with the insulin response as my blood sugar won't get to a level that triggers it.

The reason for my question is that I've also been informed elsewhere that eating carbs before exercise triggers the undesirable effect of a flood of insulin. However from what you've said I can avoid this if my levels don't get too high.

I find that without carbs, I don't see to be able to get my blood sugar level to sustain me during exercise, and am instead emptying my muscles of their glucose reserves and then my liver is spitting more out to top them up.

I guess the question really is whether its better to eat a carby breakfast before exercise, after exercise, or not at all and stick to protein, letting my bodies reserves sustain me instead of my food intake??

Sorry for all the questions; I really appreciate your insight and I feel I'm nearly there in understanding it!

 

[Northerner]

It's an individual thing, so the only real balance can be found by testing frequently to see how things go i.e. how many carbs you need to sustain you, and what would be too much. Ideally, you should choose carbs with a low GI so that they digest and release their energy slowly and steadily, then your body won't be hit by a sudden 'spike' in levels and overreact. I'm a runner and find that I do need some carbs before I go for a run, but I just have a slice of toast and that will do me for 8 miles or so - any further and I need to top up with a jelly baby or two every 15-30 mins. I usually wait for half an hour or so after eating before exercising, although I am different as I am Type 1 and need to inject insulin.

Much depends on the type of exercise and how conditioned you are to it. Anaerobic/strength exercises tend to lower levels more quickly, but again it is an individual thing. Protein and fat will convert to glucose but at a much slower rate than carbs.

Your body will use muscle glycogen as soon as you start exercising, but if you are insulin sensitive enough then this should get replenished from your blood glucose. If you don't eat carbs before exercising then your body will try to convert body fat, but this process is less efficient, so can leave you feeling tired (this is what happens to marathon runners when they hit 'The Wall').

You might be interested in reading the Diabetic Athlete's Handbook for lots of information about how everything works 🙂

 

[Seeking Motivation]

Absolutely spot on advice, it's really improved my understanding.

I'll definitely check out the handbook and hope to post again soon.

Thanks again.

 

[trophywench]

Remember though - that your body does not only produce and release insulin to deal with actual food! - we use it all the time just to breathe in and out and for every process our body performs without us noticing - eg our hearts would cease to beat, were there no insulin available!

Excess insulin encourages the body the lay down fat deposits, so if you stuff carbs then sit on your bum - you will in time, get fat.

So - if you are already round about the weight you want to be, and want to exercise just for general fitness coupled with wishing not to over-produce insulin - OK eat X amount of carbs.

However - if you actually want to lose weight - or body fat - then eat slightly less carbs than you need just for the exercise, so your body WILL try and use your fat stores - IYSWIM.

 

[Seeking Motivation]

Thanks,

I'm not 100% sure, but suspect I may be what is termed skinny fat?

In that I have a slim build and decent muscle tone built up in my 20s but now I'm in my mid 30s and have been sitting on my bum for the past few years, my general health has declined and my fitness levels fallen off a cliff.

I've also been in the bad habit of polishing off far too many carbs at the same time as doing all this loafing (pun intended) so I know I haven't done myself any favours. I have stayed fairly slim though so this has just caused me unnecessary complacency.

One thing I did wonder though, especially because I am slim and getting slimmer, is whether there will come a point that I stop losing weight, reach equilibrium and become accustomed to the energy levels eating meat and vegetables gives me? I've been eating platefuls of veg and protein but I'd be lying if i said I didn't still crave carbs and the energy boost they seemed to give me (even if I wasn't making use of it!!)

 

[trophywench]

Well like a lot of addictive habits (cos carbs are addictive) they don't appear immediately. eg when you are a teen and decide stupidly to start smoking you don't go from zilch to 20 a day, overnight.

In some ways I was lucky - born just after the War, sweets and bread still on ration. My mom was 'fine mouthed' as my husband calls it - fussy about what she ate. Rather have a small amount of something tasty and dainty than a shedload of cheap and cheerful. Beans on toast? Perhaps 3 times a year. Ditto fish and chips from the chip shop. Bought cakes? Once a week and you got ONE. Brought up to have one sugar in drinks, no more as sugar makes you fat. One slice of bread from an uncut loaf so it was thinner - but always spread with butter. Marg was used - but it was ONLY to make cakes and baking day was once a week so it was all rationed. It had to be, to last.

Pudding? - ah - must be Sunday then!

We weren't at all deprived.

So my mission in life during my two monogamies, has been to try to wean the chaps OFF their carb addictions asap but without them noticing too much! Some you win, some not quite LOL