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Stabber
07-03-2003, 07:54 PM
I'm trying something impossible. Putting on muscle while lowering bf%. :D

That being said, I have definitely put on a *little* more size in the past 2 weeks. My bf% seems the same... And I just started creatine yesterday. But, I do cardio 3 or 4 times a week sometimes on weight day. (I know to keep them at seperate times of the day) My question is can my cardio , which is mid-intensity for an hour usually, be inhibiting muscle growth or damaging my existing muscles? I never do cardio on an empty stomach and always dump protein in me when I'm done..

thanks

nejar462
07-03-2003, 08:00 PM
The Lungs and Heart are the most important muscles


Nuff Said.

SoulOfKoRea
07-03-2003, 08:13 PM
well longer durations of high intensity can be quite catabolic, but define "mid-intensity" for us, as I wouldn't know if that's just a slow jog or a fast pace walk

try HIIT if you're worried about it.

Stabber
07-03-2003, 08:19 PM
competitive tennis. A match. Singles.

the doc
07-03-2003, 09:54 PM
Originally posted by nejar462
The Lungs and Heart are the most important muscles


Nuff Said.

well the lung is not a muscle, but they along witht teh heart are definitely very important and need their own training regimen

LAM
07-03-2003, 11:28 PM
Originally posted by Stabber
I'm trying something impossible. Putting on muscle while lowering bf%. :D

That being said, I have definitely put on a *little* more size in the past 2 weeks. My bf% seems the same... And I just started creatine yesterday. But, I do cardio 3 or 4 times a week sometimes on weight day. (I know to keep them at seperate times of the day) My question is can my cardio , which is mid-intensity for an hour usually, be inhibiting muscle growth or damaging my existing muscles? I never do cardio on an empty stomach and always dump protein in me when I'm done..

thanks

you would do much better doing 15-20 minutes of HIIT on non-weight training days...

Stabber
07-03-2003, 11:52 PM
hmm maybe i should do that instead. wish i had a treadmill so i dont look like a maniac

as0l0
07-04-2003, 12:25 AM
wish i had a treadmill so i dont look like a maniac

you'd look like more of a maniac running around carrying a treadmill....

...oh wait, I see...

JuniorMint6669
07-04-2003, 01:35 AM
lol@as0l0

stabber: looking like a maniac is half the fun. plus HIIT on a treadmill is pretty difficult. Difficult as in... you may fall on your face while your trying to push the buttons to adjust the speed. Use a track, eliptical machine, or stairmaster.

ftotti10
07-04-2003, 04:11 AM
Yes do 15-20 mins of high intensity cardio. Supplemet after them as you would if it was a weight training session. You should not loose muscle doing this.

Do not do the cardio right after a weight session though

nejar462
07-04-2003, 01:23 PM
lol way to be picky doc.

aka23
07-04-2003, 05:57 PM
Originally posted by Stabber
My question is can my cardio , which is mid-intensity for an hour usually, be inhibiting muscle growth or damaging my existing muscles? I never do cardio on an empty stomach and always dump protein in me when I'm done...

During cardio the primary fuels are glucose/glycogen and fats. A small portion of energy comes from proteins, but this amount is usually insignificant. It usually only becomes significant when glycogen levels get very low. For the most part, the small amount of protein used comes from amino acid stores. If the stores are low or in certain other special situations, the body may catabolize muscle.

The risk of catabolism is dependent on exercise intensity, exercise duration, diet, when exercise is performed, and previous training, among other things:

The risk of catabolism is closely related to decreasing glycogen levels. Glycogen usage increases dramatically as intensity increases. It may take approximately 170 minutes to decrease muscle glycogen levels in half at 70% V02 max (moderate intensity endurance exercise), approximately 50 minutes at 85% V02 max (high intensity endurance execise), or 15 minutes at 150% V02 max (sprint portion of HIIT). These numbers come from The Lore of Running, by Noakes.

The size of the glycogen reserves is effected by diet and training. Glycogen reserves may be about 30% higher on a high (70%) carb diet than a moderate (45%) carb diet. Atheltic training increases the size even more. Under nearly complete glycogen depletion as might occur with a keto type diet, the risk of catabolism is very high. Under these extreme conditions, as much as 10% of the energy in a 1 hour cardio session may come from protein (amino acids reserve and muscle protein). There are certain other times where the risk is also high. First thing in the morning on an empty stomach, liver glycogen levels may be nearly empty. Muscle glycogen levels may be high, but the brain cannot use muscle glycogen. The body may use protein and/or muscle to make up for the low liver glycogen levels. The risk is also high after a weight training session since glycogen levels are low.

Answering your question, I doubt that the risk is enough to be concerned about from 1 hour of moderate intensity tennis; so long as glycogen levels are adequate at the start of the session. You mentioned that you take protein after the cardio is over. To minimize the risk of catabolism is important to have both protein and carbs in your postworkout meal, like you would after a weight training session.

I think a more important risk than catabolism is overtraining. Overtraining can result in poor muscle gains, or even muscle loss. The risk of overtraining is highest in high intensity and weight bearing type exercises. You can minimize this risk by not doing such sessions on sequential days or near leg day. If you want to train more than 3x per week, some options are to switch activities on sequential days and/or add in some lower intensity sessions.

Another overtraining risk is related to not allowing sufficient time for glycogen reserves to refill or not consuming enough carbs to refill glycogen reserves. The time needed to refill decreases as % carb in diet increases.

There are a number of other ways in which the cardio may influence weight training including muscle fiber changes, hormonal changes, increased blood flow, altered weight training performance, altered recovery, Some of these are positive, some negative, and some can be either. I think all are not big concerns under typical conditions.

frankm007
07-06-2003, 05:26 PM
so to preserve the most muscle and loose fat, cardio on non-weight training days 15-20 mins (interval training) correct?

LAM
07-06-2003, 05:56 PM
yes...I would not ingest carbs after HIIT but a meal or shake that contains proteins and EFA's. ingesting carbs will interfere with the fat burning process at this point..

Scott S
07-06-2003, 06:19 PM
Originally posted by LAM
yes...I would not ingest carbs after HIIT but a meal or shake that contains proteins and EFA's. ingesting carbs will interfere with the fat burning process at this point..

I don't claim to be an expert on HIIT or any kind of cardio, but I would disagree with this. Eat some carbs/protein right afterward. HIIT is very glycogen-intensive, as aka23 pointed out, so you must make sure your glycogen stores do not get too low.

As I understand it, HIIT causes your body to burn extra fat during the rest of the day, regardless of the food you're eating. The calories burned (and whether they are fat or not) during the exercise itself are not so important.

p_t
07-06-2003, 06:28 PM
Originally posted by the doc


well the lung is not a muscle, but they along witht teh heart are definitely very important and need their own training regimen

lol


yes with those in peak condition your body can achieve anything. And as far as wanting a treamill so people don't look at you funny is breaking the first rule of lifting. First rule being "Check your ego at the door"

LAM
07-06-2003, 06:29 PM
Originally posted by Scott S


I don't claim to be an expert on HIIT or any kind of cardio, but I would disagree with this. Eat some carbs/protein right afterward. HIIT is very glycogen-intensive, as aka23 pointed out, so you must make sure your glycogen stores do not get too low.

As I understand it, HIIT causes your body to burn extra fat during the rest of the day, regardless of the food you're eating. The calories burned (and whether they are fat or not) during the exercise itself are not so important.

you are not disagreeing with me but with medical science and human biology.

insulin suppresses lipolysis, so for optimum fat loss you don't want to ingest carbs after HIIT. It will take far less time for lipolysis to begin after a protein/fat meal then a protein/carbohydrate meal...and if the body needs sugars there is always glycogenesis

HORNEDFROGS07
07-06-2003, 07:18 PM
I dunno if cardio hurts your muscle gains, but for me, it seems to help. My cardio usually consists of 3+ miles running at around 80% intensity 3-5 times per week. When I follow a regimen like this, my weight rockets up and my muscle size and strength increase steadily. However, when I cut out the cardio, as is usually the case due to my schedule and the very limited time I have to train, my weight stagnates or drops, as do my strength and size gains. Explain that, cuz I really would like to know why.

Ross
07-07-2003, 08:21 PM
I've been training for a 5K for the last couple months by running ~20 miles a week, which is a lot more cardio than I normally do, and I've managed to maintain my weight by just eating a bit more and keeping the weights up. It's definitely possible to not lose your muscle, but gaining significant amounts while doing serious cardio will probably be pretty tough.

Scott S
07-07-2003, 09:11 PM
Originally posted by LAM
insulin suppresses lipolysis

True, insulin suppresses the state at which the body burns fat EXCLUSIVELY for fuel, but it can still use fat at any time.



and if the body needs sugars there is always glycogenesis

*That* is what we DON'T want -- the breaking down of muscle proteins to replenish glycogen stores.



I used to be a REALLY big believer in keto-type diets, but after going back and forth on it, I'm not so sure that it's as magical as I thought. After all, people have been losing fat on carb-based diets forever! (Lyle McDonald even pointed this out once.) I am now convinced that calorie balance is still the most important thing.