cardio glycogen stores

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WickStick
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cardio glycogen stores

Post by WickStick » Fri Aug 02, 2013 6:43 pm

Hi all,

I am training for a sprint triathlon, which requires a ton of cardio training.

This is the short version:

(1) How long does it take for chronic cardio to dig into glycogen stores and
(2) If I am digging into glycogen stores via cardio, how should I be eating prior and post workout? Similar to weightlifting (i.e. carbs and proteins)



Long version starts here:
My schedule is usually:

Day 1: 20 mile bike or 1 hr biking (whichever is hit first, usually about the same time)

Day 2: 3 mile run (ramping this up to 4 soon...I just get sooo bored...)

Day 3: Brick: 9 mile bike and 3 mile run (I do bike 9 miles back at a pretty easy pace)

Day 4: 1 mile warmup run, Full body lifting* with swimming after

Day 5: rest:

Then rinse and repeat essentially.

Some of the running is hill work (interval training) but sections of the run are flat. The biking is similar--some hills, not too bad. So it is partially interval and partially chronic cardio. However, these workouts are on the order of 30 minutes to 2 hrs long depending on the day (bricks hurt). I imagine I am cutting into glycogen stores at this point. Am I correct in this assertion? If so, I want them replenished for the next day (which is lifting). So far my lifting has been fine. I am slowly gaining strength... And I have lost about 5 lbs in the month of training and it looks like all fat according to the mirror test...So it doesn't look like the cardio is cutting into my muscle. I usually down a protein shake with milk before and after the workout and things have been dandy...but I am always for improving the diet

Thanks in advance for any help!
Rob



*note For full body lifting I do :5x5 smith squats, 5x1 deadlift, 5x5 bench, 3 sets of pullups (as many as i can--usually ends up 12-6-3), 3 sets of military dumbell press (go to failure on each set, usually 10-8-5), some decline pushups (2 sets of as many as i can), situps (2 sets of as many as I can), and I stretch a little after.

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Dub
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Re: cardio glycogen stores

Post by Dub » Sat Aug 03, 2013 8:49 am

1) It depends.
The duration and the intensity of the exercise coupled with individual energy metabolism decide how much you glycogen is going to be used. When exercising, you use all energy systems all the time, so you burn fat and use muscle and liver glycogen all the time. But the intensity and length of the exercise is important. On low intensity, like an hour or more of aerobic exercise (50-65% or so of Vo2Max) will use mostly fat stores. When the intensity rises, so does the use of muscle glycogen. It doesn't take time, it takes intensity. Your fat storages will last for hours and hours, if the intensity is low enough. When you crank up the intensity, more glycogen is getting used. Depending on how hard you are going and how well you have eaten, glycogen stores will last everywhere from half an hour to two hours or more.

Interval training will deplete your glycogen storages more than low intensity aerobic exercise. 2 hour exercise will most likely use some muscle glycogen (again, depending on the intensity). I can't tell if you are draining the storages with this information. It's more like how do you feel? There's a special feeling when your body turns to more fat-based metabolism while doing higher intensity cardio. Your performance will decrease and it will hit you mentally as well.

2) Eat carbs and protein before and after the workout. A good meal 2-3 hours before the exercise is good for pre-workout. Then if you have more depletion on glycogen storages, hit a small amount of carbs (30g is enough, but you can do more) and some protein post workout to start your recovery process, then eat a big meal an hour or so afterwards. If the exercise wasn't that intense, you can just eat a meal like 45min - 1h after the exercise. No stress. You are training only once a day, so instant recovery process isn't necessary, just eat enough carbs around your workouts and you will have enough glycogen in your storages.

When competing, if the competition lasts for more than 90 - 120min, take some fast-acting carbs slowly during the competition to keep your glycogen going.
Physical Preparedness Coach
Co-Owner of UniFit Oy.

WickStick
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Re: cardio glycogen stores

Post by WickStick » Sat Aug 03, 2013 10:00 am

Thanks Dub, this was incredibly helpful.


The only part where I am really huffing and puffing is the uphill run--which took me like 15 minutes. The rest of it I am breathing deeper than normal but certainly not gasping for air.

This morning I feel a little sore, but still pretty great, so it sounds like either I am not doing an intense enough workout to dig into glycogen stores (to me this is fine, this stage of training is simply to get used to being on a bike for forever,,,plus fat loss!) or my eating is giving me some solid recovery.

I will put some sugar or honey in my water bottle post swimming to keep it going.

Thanks!

Rob

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Jungledoc
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Re: cardio glycogen stores

Post by Jungledoc » Sun Aug 04, 2013 2:31 pm

I'm exhausted just reading about it!
Our greatest fear should not be of failure, but of succeeding at things in life that don't really matter.--Francis Chan

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