playing around with fasted training

[ElyDave]

Decided to go with a 90 min bike session this morning instead of running. This time, instead of carbing up, I decided to set out early and have breakfast when I got home.

So, wake up at 5.2
Quick cup of coffee whilst watching Transvulcania highlights, rose to 7.2, no bolus, reduced basal of 1.0 U

as it was an experiment, I decided to test every 30 min instead of 45
30min 5.7
60 mins 4.9, had a fig roll just in case
90 mins 4.8

Breakfast at home with a bolus reduced by a third, 22.5g carbs.

Pretty happy with that overall and wil try that again, but maybe a longer session, also a longer run - I've done a couple of short fasted runs before.

It was glorious weather for it as well.

 

[ElyDave]

A bit more fasted training this week while away and thsi morning.

I've definitely come to the conclusion that hill reps, speedowrk etc is not for the morning.

On two runs of 8-10km this week, my BG varied no more than the tolerance of the meter. This morning's run was planned at 20-25km, ended up at 21. No bolus before hand, 1 unit basal vs the normal 3-3.5, cup of coffee and a fig roll and up to 6.7 before I set out.

Steady paced effort about 5:30/km, went like this
5km - 5.8 - 8g carbs
10km - 5.9 - 8g carbs
15km - 4.8 - 10g carbs
21km - 4.9 - 10g carbs during this 6km.

half an hour later befroe breakfast - 7.3, 40g carbs with bolus reduced by 1/3. 2 hours later 6.0.

So, compared with the textbook figures of 60g plus per hour, that was a smidge under 2 hours on 50g carbs. A good fat burning session, training that mechanism hopefully.

 

[Bebo321]

A bit more fasted training this week while away and thsi morning.

I've definitely come to the conclusion that hill reps, speedowrk etc is not for the morning.

On two runs of 8-10km this week, my BG varied no more than the tolerance of the meter. This morning's run was planned at 20-25km, ended up at 21. No bolus before hand, 1 unit basal vs the normal 3-3.5, cup of coffee and a fig roll and up to 6.7 before I set out.

Steady paced effort about 5:30/km, went like this
5km - 5.8 - 8g carbs
10km - 5.9 - 8g carbs
15km - 4.8 - 10g carbs
21km - 4.9 - 10g carbs during this 6km.

half an hour later befroe breakfast - 7.3, 40g carbs with bolus reduced by 1/3. 2 hours later 6.0.

So, compared with the textbook figures of 60g plus per hour, that was a smidge under 2 hours on 50g carbs. A good fat burning session, training that mechanism hopefully.

Thanks for the data Ely Dave,
Apologies if you have already mentioned this elsewhere, but I wondered if you follow any particular diet (LCHF) etc? I have heard from some that eating a diet lower in carb seems to reduce fluctuations of BG during exercise - I wondered what your experience was, and what your own observations were around diet and exercise/blood glucose control etc.

 

[ElyDave]

Thanks for the data Ely Dave,
Apologies if you have already mentioned this elsewhere, but I wondered if you follow any particular diet (LCHF) etc? I have heard from some that eating a diet lower in carb seems to reduce fluctuations of BG during exercise - I wondered what your experience was, and what your own observations were around diet and exercise/blood glucose control etc.

No particular diet, moderate carb, try adn keep it around 100g a day or so, which seems to be working so far. Apart from race days and long training so far when I've been letting it go higher.

How did your other half get on in the Half Iron Man?

 

[Bebo321]

No particular diet, moderate carb, try adn keep it around 100g a day or so, which seems to be working so far. Apart from race days and long training so far when I've been letting it go higher.

How did your other half get on in the Half Iron Man?

100g a day sounds nice and manageable.
I am amazed at how low you can keep your carbing - the 21km run above was stunning!

Hubby had fun, but didn't do such a good job, in that he decided to have a big bowl of pasta and bolognese late the night before, then no breakfast and then nothing but gels! - one too many because he ended up not being able to keep them down and even though he was making good time on the bike he decided to call it a day after the first lap of the cycle.
I think it came as a bit of a shock with not having had that problem before, but in hindsight I guess gels hitting undigested dinner all shaken up with exercise and nervous energy is a recipe for disaster!

Odd really how for some reason the competition environment changes what you would normally sensibly do - also how much the hormones come into play and cause havoc with BGs
The competition environment will always throw a spanner in the works, so it's just a case of doing more events to be able to get the loading nailed in all situations.

Never mind - he's got to focus on cycling from Barcelona to Vienna at the end of August now. He's used to managing carb loading with endurance cycling, so he'll be back on familiar ground with that.

I quite fancy getting a bit fitter myself now - I started cycling not that long ago, and really enjoy it. I already like to do a bit of running (only 10k or so tops around our hills). Swimming might be fun to add into the mix, and then I can see if I can manage a triathlon.

What's your next event? Is there something in particular you are training for?

 

[ElyDave]

@Bebo321 that sounds nasty. He wasn't by any chance making the schoolboy error of changing something on race day and only eating gels?

Sounds like not enough time to digest the meal before hand, tbh that's too late for carb loading to be effective. I'd be slowing right down to only a little more than normal if I were trying to carb load, not that I do that, I perfer to try and train the fat metabolism to be more effective.

I'm not one to talk though buying compression shorts the week before a race and using them for the first time in my most recent race. 10km in I was in all sorts of pain, glad it worked its way off though as only th efund raising kept me going for a while.

Adrenaline and race conditions always change things, but you just need to be aware enough to react, take me stopping drinking as my hands swelled in the heat on the fell race thinking it was overhydration . Combination of heat, adrenaline and general stupidity.

Barcelona to Vienna sounds great, I'm just researching bike hire in Salzburg for a July holiday and then the next race is a 40-miler on the 1st August.

 

[Bebo321]

@Bebo321 that sounds nasty. He wasn't by any chance making the schoolboy error of changing something on race day and only eating gels?

Sounds like not enough time to digest the meal before hand, tbh that's too late for carb loading to be effective. I'd be slowing right down to only a little more than normal if I were trying to carb load, not that I do that, I perfer to try and train the fat metabolism to be more effective.

I'm not one to talk though buying compression shorts the week before a race and using them for the first time in my most recent race. 10km in I was in all sorts of pain, glad it worked its way off though as only th efund raising kept me going for a while.

Adrenaline and race conditions always change things, but you just need to be aware enough to react, take me stopping drinking as my hands swelled in the heat on the fell race thinking it was overhydration . Combination of heat, adrenaline and general stupidity.

Barcelona to Vienna sounds great, I'm just researching bike hire in Salzburg for a July holiday and then the next race is a 40-miler on the 1st August.

Lol!
Glad to know he's not the only one who makes the mistake of changes tactics on race day! You're right - schoolboy error. Particularly carb loading the night before when actually much like you his diet is generally low carb - more like 50g a day! His stomach didn't appreciate it.

Cycling around Salzburg should be lovely - although I haven't been, it's supposed to cater well to cyclists.
Hope you have a fantastic time! Not jealous at all!

A forty mile run?!! Are you serious?! What do you use to fuel that and how often? - could you keep going at your 21km loading of 8-10g per 30mins - what point will you need to increase that?
Just out of interest, I recall another runner (type2) on the forum getting quite techy about heart rate monitoring, to ensure that their body burns a higher proportion of fats (free fats acids etc) to glucose. (So basically keeping their heart rate a little lower). Do you do anything like that, or have you run so much that you just know your own body?

Hoping training is going well. Stunning morning here, so we're off out on a cycle.

 

[ElyDave]

for that 40-miler it will be a combination of things like gels for some quick release, and date/oat/nut bars for a more measured release, along with fig rolls and belvita biscuits to keep the interest up. Over that distance you need a bit of protein as well. The camelback will have Nuun in it as for running I prefer to slow to a walk, eat and then run again rather than drinking carbs as I go (much easier on the bike).

I've been doing HR based training for years. Every year I have a period where I do not allow my HR outside my aerobic zone, base building is very much misunderstood and under utilised. One of the reasons as you mention is to try and get that fat burning metabolism effective as that gives you the base. IN race conditions, you want to be starting with a good base so the redline comes much later and much faster.

 

[ElyDave]

So today, another go at extended fasted training in the morning.

Main reason for doing this? Effective fat burning metabolism, which you can't get if you are full of insulin.

Morning - coffee, one unit basal. One fig roll as I'd woken at 4.6 (consistent for me at the moment even with reduced evening basal)

Pre ride - 6.2
45min 4.9, 10g carbs taken
90min 4.2, 23g carbs
120min 5.4
breakfast 45g carbs, reduced bolus 1.5 units vs normal 3

45 mins later - 6.2
2 hours later after doing the grocery shopping 5.4

seems to have worked that was 2 hours cycling at just about 19mph on 45g carbs in total with a slighlty larger than normal breakfast to follow.

Unneccesary carbs avoided approx 45-60g

 

[hale710]

I too am starting fasted "training"... Not to the extreme of yours though.

My waking BG is usually about 8 so I'm confident to go out for a 2.5k with no snack at 5am

I'm still finding that I rise initially, so I finish around 12. I don't correct this at it falls itself within the hour. Not sure if it's because my body still thinks a 15 min run is a sprint (average 7min/km so not exactly speedy!) or if it's because it's in the morning and I've no food so liver is playing games. I've considered trying breakfast first with a reduced bolus but I can't stomach food that early!

Thoughts?


Blogging at drivendiabetic.wordpress.com

 

[ElyDave]

I too am starting fasted "training"... Not to the extreme of yours though.

My waking BG is usually about 8 so I'm confident to go out for a 2.5k with no snack at 5am

I'm still finding that I rise initially, so I finish around 12. I don't correct this at it falls itself within the hour. Not sure if it's because my body still thinks a 15 min run is a sprint (average 7min/km so not exactly speedy!) or if it's because it's in the morning and I've no food so liver is playing games. I've considered trying breakfast first with a reduced bolus but I can't stomach food that early!

Thoughts?


Blogging at drivendiabetic.wordpress.com

Glad to see you're still around!

I woudl stick with what you are doing to be honest. Eating first will just result in a full belly and possible gastric issues unless you are waking up early enoug to eat three hours before exercising?

Not having breakfast will not affect your capabilities over that distance/duration.

Overall it sounds like you are doing just fine with it. I get the same rise for short distance fasted exercise, and like you it settles back down again quickly.

 

[oldgreymare]

So today, another go at extended fasted training in the morning.

Main reason for doing this? Effective fat burning metabolism, which you can't get if you are full of insulin.

Morning - coffee, one unit basal. One fig roll as I'd woken at 4.6 (consistent for me at the moment even with reduced evening basal)

Pre ride - 6.2
45min 4.9, 10g carbs taken
90min 4.2, 23g carbs
120min 5.4
breakfast 45g carbs, reduced bolus 1.5 units vs normal 3

45 mins later - 6.2
2 hours later after doing the grocery shopping 5.4

seems to have worked that was 2 hours cycling at just about 19mph on 45g carbs in total with a slighlty larger than normal breakfast to follow.

Unneccesary carbs avoided approx 45-60g

Really interesting following your posts and your blog. Have you come across Peter Attia's blog The Eating Academy? American scientist and endurance athlete. He's done quite alot of detailed research on his own responses to lowering carbs and exercise. (Not diabetic but was pre-diabetc in spite of being a marathon swimmer when he first started looking into whether carbs are critical for sport). Many articles on his blog so can't remember in which post he identified that for endurance activities he saw no decrease in his speed, strength etc by staying low carb, but did see some some drop-off in explosive max strength - nor surprising as this is totally glycogen dependent?

See http://eatingacademy.com/category/sports-and-nutrition

HINT - he's a great source of info but it helps if you like biochemistry...