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Carbs for Aerobic Activity?

It seems most people on this site follow low carb diets and do not do much cardio (which I have been doing up to now)…but I would like to know: how many carbs are actually required to support aerobic activity (while continuing to lose fat/maintain muscle)?

While on a low carb diet (~100g carbs/day), I generally do 45 minutes cardio 3 times per week. I would like to up my cardio to 90-120minutes/day, mostly high intensity (for various athletic/training/health reasons). Approx. how many grams should I add to my diet to support this? I still have lots of fat to lose so I don’t want to eat more than is necessary.

Any suggestions? Thanks.

If its high intensity cardio then yes it largely relies on glycogen (fast) fuel for the workout and you’ll want to replace that prior to weights and make sure you have enough.

If low carbing the body will go through the limited stores you have and turn to the conversion of aminos to make glocogen, either aminos in the blood or once gone conversion of muscle tissue.

90-120 mins of constant high intensity cardio is going to use a LOT of glycogen an exact # who knows but you’d be wise to have a dillute drink on hand if preservation of LBM is priority.

Then you have low intensioty cardio. Non panting which relies nearly purely on fat for fuel (slow source) but that doesnt fit your atheletic goals but can be used.

Drink something like gatorade during your long high intensity sessions and no worries your metabolism will be jacked after the event and not running high speed so will burn fat and if you want further fat loss and more than likely aid recovery go for walks etc.

I suggest you search for and read the cardio roundtable series.

Phill

[quote]Jade1 wrote:

While on a low carb diet (~100g carbs/day), I generally do 45 minutes cardio 3 times per week. I would like to up my cardio to 90-120minutes/day, mostly high intensity (for various athletic/training/health reasons). [/quote]

Up to two hours of energy system work per day, most of which is high intensity stuff… are you sure a low carb diet as outlined in your post is the right thing in that case?

What does your training look like exactly?

[quote]michael2507 wrote:
Jade1 wrote:

Up to two hours of energy system work per day, most of which is high intensity stuff… are you sure a low carb diet as outlined in your post is the right thing in that case?

What does your training look like exactly?
[/quote]

No, a low carb diet isn’t going to work for the aerobic activity I want to do…but I’m so “programmed” with a low-carb mentality that I am not sure how to adjust my diet so I’m not eating to much or too little!

Right now I’ve cut back on weights due to back problems. I still do a few weight sessions a week but not as high intensity as I was doing previously (not many compound lifts, mostly isolation/body weight exercises).

My back will be okay in a month or so of “active rest”…but in the mean time I decided to work on my cardiovascular ability…which has been completely ignored for several years. At first, I was worried about muscle loss…but honestly I’ve never felt better- more energy, my lungs feel good (along with weight gain, I smoked over the past year yuck!- I’ve quit now) and I feel pumped that when I go back to weights “full-time” I will have better recovery time.

Currently I’ve just done one 45-60 min session per day (5-6 days per week)…consisting of high resistance work on gym equipment (tredmill, x-trainer, bike), interval training (HITT) and some low intensity work. The high resistance (walking up hill) still makes my legs work. Basically I’ve just been adding extra Surge to my “low carb” diet.

I want to add a second 45 min session outside at the track, modelled after my old sport training (drills, stair running, etc.). Could I just add a second serving of Surge? Or is that not enough?

A few years back I was a pretty good athlete. I played on several sports teams and trained 3-4 hours a day (2 practices and a gym session). At that time though I wasn’t fat, so I just ate as much as wanted when I was hungry (lots of protein and lots of carbs). I didn’t count calories or carbs. Now, I am fat. I’d like to do the cardio work I outlined above but feel that I should be more particular about my diet so I can continue to lose fat.