Workout Energy Crashes

So I'm not new to weight loss or fitness...I've been hitting it hard this year since like February. Just last week I decided to switch from outdoors and at home DVD programs to elliptical machines at the gym. I also brought myself down to a 1300 calorie intake which is relatively normal too...I had been bingeing and completely off track until mid last week. I aim for a 600 calorie burn when I work out...I have a heart rate monitor that I used to track calories. About 2 days after I started this gym thing, my energy has been crashing at about 25 minutes in. It's like dizziness, shakiness, weakness. Sometimes I can push through but I have to go at a low-moderate pace, or I quit altogether like I did tonight.

I don't know what is causing this. I've had blood sugar drops from workouts before but not that early and usually I get ravenously hungry for sugar...this isn't like that. I make sure to eat fruit and something else before each workout and that still doesn't seem to stop the crashing.

Has anybody experienced this? It just seems like if it's because I'm not eating enough, I'd just be a lot hungrier...and that's not the case. It's REALLY frustrating.

Replies

YoukilledJosh

I only feel like that if I dont eat enough

scithighs

It wouldn't hurt to get as glucose monitor and check your blood sugar when you feel like that. I loose all energy when my blood sugar drops and can't work out. Eat something with protien before you work out too!.

tinad120

I only feel like that if I dont eat enough

Same here. Do you usually get a pre-workout snack?

falcon367

I'm not you so its hard to know exactly whats going on. What I can say is that 1300 might be too little nutrition for someone hitting it hard every day. Without knowing your height, weight, age and general activity level, your TDEE is hard to determine and that is how you should be setting calories. Anything grossly under nourished for a sustained period of time and you will start to bonk. If you were anything like myself, I was able to sustain a severely low calorie cut for about 75 days while my body fed off my body fat and what little I was eating .. then as that diminished, it started turning on my muscle mass and I literally started to shrink ... and crash during exercise.

There are many great sites around that talk about TDEE, BMR, etc. that you should consider. As an example, a 30 yr old, 5' 6" woman weighing 140 lb has a TDEE of about 1649. That number is what your body needs to function for someone with a desk job. Add in your 600 calorie workout and you are now at -949 deficit for what your body requires to stay functioning throughout the day.

Here are some links that are useful:

http://www.myfitnesspal.com/topics/show/654536-in-place-of-a-road-map-2-0-revised-7-2-12

http://forum.bodybuilding.com/showthread.php?t=121703981

http://scoobysworkshop.com/accurate-calorie-calculator/

drivenheart85

Yes, I do have a pre-workout snack...today was an apple, greek yogurt and some almonds.

As for BMR, I'm 5' 7", 27 years old, about 150 lbs and work a desk job. Fitness pal says my BMR is around 1800. So with a 500 cal food deficit and 600 cal workout, that's an 1,100 cal deficit. That deficit IS technically over the 1,000 daily deficit limit....1,000 cal deficit a day equals 2 pound loss a week. I do the extra 100 in there though for my day off of exercise...that day would only be 500 cal deficit due to no workout but the 6 days of an extra accrued 100 cals brings me exactly to a weekly deficit of 7,000 cals. I have this all in an Excel spreadsheet...I'm kinda nuts about it. lol So really, I'm technically within standard limits.

The other things I'm thinking of is maybe I screwed up my blood sugar levels. I binged on HIGH sugar foods early last week...maybe it messed with my blood chemistry somehow.

The other reason I don't think it's starvation is that I've only put myself on the 1300 cals a day for like a week so far...if I'd been doing this for more than a month, I could understand. But my body has been overfed since like August...it can't write me a sob story about being hungry. lol

2nd option could be a caffeine crash, although I've experienced this during times when I shouldn't have had a caffeine crash.

3rd option...other than sacrificing my 2lbs a week goal, I could rearrange my meals, so that I have at least 1,000-1,100 of my calories in BEFORE I work out. So heavy on breakfast, lunch and snack, then cut back after the workout.

I guess I'm going to have to do some experimenting. I just HATE to see my workouts cut in half.