Cardio and muscle burn

[Big Vin]

At 46 I'm starting to make the transition into "more of an athlete" and not just a weightlifter/bodybuilder any more. I've stripped most of the bulk and am now sitting at 6'0 ...220 lbs. I still weight train mostly for endurance, but with moderate weight 8-10 reps and short rest (20-30 seconds). Not looking for any more bulk. Have the BF at about 12% now and going to bring it down to 10% or so. I have a weightlifters body and not a runners body.
I do fasted running 6 days a week in the early morning. Alternate intervals with distance training. Also have a few 5K's under my belt to show for it.
I was always told (and am sure a lot of you have been told this as well)..."any cardio over 40-45 minutes starts to burn muscle".
Do you guys still subscribe to this theory? and does it apply if one is using AS (I stick to mainly test/winny/var/mast and use as little as I can get away with)?
Reason I'm asking is that doing this much cardio is relatively new to me. I'm starting to train for 10K's now and eventually half marathons....this means a lot of 1+ hour runs...
Not looking to lose muscle obviously...but what is the point of diminishing return? Should I stick to 5K's and short runs...or can I go for the longer stuff while retaining muscle?

 

[alfresco]

Big Vin,

My opinion . . . I do not know where “your” point of diminishing returns is. Nobody does but you.
And I don’t know about the afore mentioned "any cardio over 40-45 minutes starts to burn muscle"
but generally speaking; distance runners have less muscular mass than sprinters. One would have to
be blind not to acknowledge that. I think you would have to be some kind of genetic freak to maintain
a huge amount of muscular mass if you plan on running half marathons or one hour plus runs. Maintain
or growing and those kinds of activities are mutually exclusive, i.e., you can have one or the other,
not both.

If you have a “weightlifters body” then that might be to your advantage in some regards to lose weight
first. Advantages, disadvantages. Some good, some bad. I’m thinking injuries. “Heavy” people should
not run in my opinion, too much impact -- stress on the body, but I am veering off the subject . . .

I have been accused of having a runners body, a swimmers body, a gymnasts body but only once of a
bodybuilders body (you would have to know the circumstances). All observations were sincere and
not taken personally. I am what I am. I am somewhere in-between. I will never be outstanding or
great in either activity (I have been tested for fiber type) but can “survive” in either activity which will
be largely training dependent, i.e., meaning I am in the middle . . . I can do either activity just don’t
expect spectacular results whatever path I choose. Que sera sarah.

Case in point . . . for example . . . this morning I went to the gym and did 30 minutes on the Concept II
rowing machine burning ~ 400C per hr. as a warm up to working legs. Then I did leg presses, adductor,
abductor, walking lunges, toe presses and 45 minutes of stretching. Then I went on a two hour hike
(if there was a piece of level ground of ground, I did not find it) and then on a hour and half bike ride
where I saw Levi Leipheimer (a Tour De France cyclist) passed me while being drafted by a Vespa driven
by his wife, @ ~ 30mph. Having seen Levi in person, literally a world class endurance athlete, (he trains
at the gym I belong to, lives a few miles away) my first impression is that he should gain a few pounds;
but when I heard the upshot of his talk; he said he was “over-weight.” Such is the mentality of endurance
athletes. If you are a “bodybuilder” who is venturing into the endurance type activities, just be mindful
of that mentality. You can be one or the other, rarely can you have both at a level that meets or exceeds
your expectations.

Is the training I did today conducive to the growing muscular mass? Of course not. My activities, though
not “normal” for your typical professionalmucle.com-er, is in many regards typical for me, I want to have
my cake and eat it too. But the sometimes harsh reality is . . . long story short . . . the longer you run,
the more cardio you do, generally speaking, the less muscle you will have. (Personally, I think cardio
is highly overrated when it comes to weight loss – contest preparation.) And of course this disclaimer
always applies . . . your mileage will vary.

I wish you all the best in your endeavor. Hope this helps . . .

 

[Ragin8]

The notion that your body will become myogenically proteolytic merely through virtue of 40-45 minutes of cardio is based on unfounded pseudoscience.

The body is well adapted to long durations of aerobic and anaerobic stress. Your body will utilize muscle glycogen and large stores of liver glycogen. Hell, even free amino acids in blood will be utilized before muscle gets broken down.

You shouldn't have anything to worry about, assuming you aren't going on the Ethiopian starvation diet.

 

[Big Vin]

This is all good stuff. I'm up near 300 grams of protein per day and will keep up that intake. Total caloric intake is right around 3000 per day.
I have one more 5K coming up the weekend, then it's on to 10K training. Yes, it's more difficult for guys my size/age to run distance. Moving 220 pounds through the streets for half marathon, 10K or even 5K is hard work. Luckily, my knees are in good shape so far.
I guess I'm just going to have to see how it plays out.

 

[mymre21]

The notion that your body will become myogenically proteolytic merely through virtue of 40-45 minutes of cardio is based on unfounded pseudoscience.

The body is well adapted to long durations of aerobic and anaerobic stress. Your body will utilize muscle glycogen and large stores of liver glycogen. Hell, even free amino acids in blood will be utilized before muscle gets broken down.

You shouldn't have anything to worry about, assuming you aren't going on the Ethiopian starvation diet.

:yeahthat:

agreed..it would be determined on your diet if there is muscle atrophy