Help me understand what's going on with my body?

September 27, 2009 11:19 PM

Questions about glycogen stores, hypoglycemia, carbs (specific situation inside)

Last night I didn't have an appetite so barely ate dinner. This morning I woke up, had a coffee, 1/2 a banana, 2 spoons of muesli and did 3 sets of plyometric intervals (20 seconds on, 10 seconds rest x 8). Immediately afterwards I felt dizzy. I realised my blood sugar was low so I had about 300ml of orange juice, then scoffed down a wholegrain sandwich with 2 eggs. My blood sugar didn't go back to normal, so I had a little more juice, then after about half an hour I had about 5 tsps of sugar, which seemd to help a bit, so then I had 1/2 a scoop of protein as my doctor suggested this might help when I get hypoglycemic. I felt a bit better but still a bit weird. Then on the train to work I started feeling a bit more scattered so (maybe 1 hour later) I had a muesli bar (25g protein, 6g fat, 4g protein), then I still felt awful half an hour later so I had about 400ml fruit juice, followed by a scoop of whey protein. I started to feel a bit better, then a bit later I started to feel hungry and a bit weird so I ate 1/2 cup of porridge. I continued to feel better after that but had a massive headache.

Basically, my theory is that
a) I depleted my glycogen levels
b) I shouldn't have had the sandwich as that probably slowed digestion of the sugars

Does this sound right?

And now,

a) am I going to put all the stuff I ate afterwards on as fat?
b) should I train this evening (12 hours after morning training) or will my glycogen levels still be too low
c) should I eat normally for the rest of the day, or should I not eat much because I ate so much this morning?
d) would it have helped to have eaten more before exercising this morning?
e) would it have been ok to have done this on an empty stomach this morning if I'd had more carbs last night?

I am a 55kg/166cm female if that helps, recently increased my food intake and went up from 53kg to try to stop this stuff happening, but scared it's going to go keep going up!

posted by Chrysalis to health & fitness (7 comments total)

Also
a) If I train tonight (it'll be a rather intense 1-1.5 hour session) am I likely to get low blood sugar again afterwards cos of what happened this morning? Should I sip gatorade throughout? (would that help?)
posted by Chrysalis at 11:28 PM on September 27

Most estimates for total-body glycogen stores are in the 1,600-2,000 kCal range. There's no possible way you burned anything close to that in 4 minutes of exercise, so glycogen debt seems like an unlikely explanation.

I'm not hypoglycemic so I can't comment on all the digestive stuff, but I've definitely had my ass kicked in 4 minutes of intervals before; it sounds like you just pushed too hard and got overworked. It's normal to feel a bit crappy after a solid set of intervals - were you working harder than usual this morning? If you're feeling OK, I wouldn't see a problem doing a 1-1.5 hour aerobic work-out, but doing another set of intervals or other anaerobic activity is probably going to make you feel worse.
posted by 0xFCAF at 11:38 PM on September 27

Sorry, I did 3 sets of the 4 minute intervals... not a huge amount but I'm coming back from a layoff. The only thing that made me think it might be that is that on Friday night I did a big session, then waited a couple of hours to eat (stupid) - and ended up eating way too much also, cos I was starving.

I'm supposed to be doing boxing sparring tonight, and probably some light weights afterwards...
posted by Chrysalis at 11:51 PM on September 27

How do know you blood sugar was low, were you using a glucometer? If so, what were the readings?

To me if sounds like you had a deficit because of skipping dinner and never really made up for that. Also, I was taught by trainers I respect to never exercise on an empty stomach.
posted by Brandon Blatcher at 3:53 AM on September 28

Did you drink any alcohol the previous night?

As for digestion, generally if I eat anything in concert with something sugary, I'll digest it all more quickly. I also know I can slow digestion greatly by being too low on hydration, or having my 'lytes off.

I've also had a meal of simple sugars and protein and was surprised to see my blood sugar dip in between digestion of the two, so copious amounts of complex carbs are important. It sounds like you kept eating simple carbs and proteins, except for the two slices of wholegrain bread. That'd be hell in my book, pretty much exactly as you describe too.
posted by jwells at 5:25 AM on September 28

I would echo the call to actually test your blood sugar. I believe there are ways to calculate the difference between what your blood sugar IS and what it will be when your food starts to digest. Probably similar to what diabetics do to calculate how much insulin to inject.

Gatoraid is probably a good choice for instant blood sugar recovery, or orange juice with a little salt in it. Something about the glucose+salt combo (on an empty stomach) speeds absorption.
posted by gjc at 6:41 AM on September 28

The same exact thing happened to me a couple weeks ago-- it took all day for me to feel back to normal, and that was with me drinking lots of sugary stuff to try and get my blood sugar up. It happened because I had skipped dinner the night before and only had a glass of milk and some cheese the next morning, before doing an intense weightlifting session with my trainer.

Now I always make sure to have something to eat with carbs at least 30 mins before an intense workout.
posted by np312 at 10:58 AM on September 28