The best way to get a good Fat Loss to Muscle Loss ratio during exercise
- 05-22-2006, 08:42 PM
The best way to get a good Fat Loss to Muscle Loss ratio during exercise
Bottom line is keep the workouts to less then or equal to 45% VO2 Max for the best fat burning results that wont destroy muscle mass.
Balance of carbohydrate and lipid utilization during exercise: the "crossover" concept
G. A. Brooks and J. Mercier
Department of Human Biodynamics, University of California, Berkeley 94720.
The "crossover" concept represents a theoretical means by which one can understand the effects of exercise intensity and prior endurance training on the balance of carbohydrate (CHO) and lipid metabolism during sustained exercise. According to the crossover concept, endurance training results in muscular biochemical adaptations that enhance lipid oxidation as well as decrease the sympathetic nervous system responses to given submaximal exercise stresses. These adaptations promote lipid oxidation during mild- to moderate-intensity exercise. In contrast, increases in exercise intensity are conceived to increase contraction-induced muscle glycogenolysis, alter the pattern of fiber type recruitment, and increase sympathetic nervous system activity. Therefore the pattern of substrate utilization in an individual at any point in time depends on the interaction between exercise intensity-induced responses (which increase CHO utilization) and endurance training-induced responses (which promote lipid oxidation). The crossover point is the power output at which energy from CHO-derived fuels predominates over energy from lipids, with further increases in power eliciting a relative increment in CHO utilization and a decrement in lipid oxidation. The contemporary literature contains data indicating that, after endurance training, exercise at low intensities (< or = 45% maximal O2 uptake) is accomplished with lipid as the main substrate. In contrast, the literature also contains reports that are interpreted to indicate that during hard-intensity exercise (approximately 75% maximal O2 uptake) CHO is the predominant substrate. Seen within the context of the crossover concept these apparently divergent results are, in fact, consistent.(ABSTRACT TRUNCATED AT 250 WORDS)PharmD
- 05-22-2006, 09:17 PM
05-22-2006, 09:29 PM
Awesome, thanks Lake. This just further supports the diea that low intensity cardio is superior for anti-catabolism. Unfortunately, its the process that takes the longest.
I guess this would support the idea of doing low intensity cardio after weight training as it wouldn't go straight for glycogen ergo depriving the body of further replenishment. I wonder if there are any effects with the introduction of a source of Carb during low cardio exercising. Just thinking out loud.
05-22-2006, 10:04 PM
Good thoughts Rage. I remember some years back (when I was working in the performance lab at school we used to do similar tests and have subjects do two different bouts of exercise at the same intensity spaced out by a number of days. One bout would be fasting with no carbs added and the second bout would be with carbs added during the exercise. Reletivly low intensity 60%. Each time the carbs were given to all subjects the RPE decreased and their RER increased. Meaning the exercise seemed easier and they were using more CHO relative to FAT. So it will probably still cause a shift to carbn burning instead of fat.
Originally Posted by Rage (SoCal)
05-22-2006, 10:19 PM
HOWEVER if you go in the bulking section and read the thread on a shake during workouts I posted 3 studies saying that it decreases serum GH, testosterone, and free fatty acid levels, meaning more burning of CHO.Originally Posted by Mr.50
05-22-2006, 10:23 PM
Lake I don't think that is actually a HOWEVER, I actually think that we are in agreement (my post above and yours right below it). I have also nticed that I had great results bulking when I was younger with a carb intake during my lifting workouts. Of course I really don't bulk anymore so I am not to sure if I was just young or it was truely some positive effect. I realize that it may lower GH and test but I think this is partly offset by the large increase in insulin during the workout.
Originally Posted by LakeMountD
05-22-2006, 10:29 PM
OH sorry about that I misunderstood. here are the studies tho
Protein Ingestion Prior to Strength Exercise Affects Blood Hormones and Metabolism.
Medicine & Science in Sports & Exercise. 37(11):1990-1997, November 2005.
HULMI, JUHA J. 1; VOLEK, JEFF S. 2; SELANNE, HARRI 3; MERO, ANTTI A. 1
Purpose: The effects of protein consumption before strength training session on blood hormones, energy metabolites, RER, and excess postexercise oxygen consumption (EPOC) were examined.
Methods: Ten resistance-trained young men consumed either a 25 g of whey and caseinate proteins (PROT) or a noncaloric placebo (P) in a liquid form 30 min before a heavy strength training session (STS) in a crossover design separated by at least 7 d. STS lasted 50 min and included 5 x 1 RM squats, 3 x 10 RM squats and 4 x 10 RM leg presses with 2-, 3-, and 2-min recoveries, respectively. A protein-carbohydrate supplement was consumed after STS in both trials. Venous blood samples were collected before, during, and after STS and oxygen consumption before and after STS.
Results: Serum growth hormone (GH), testosterone, and free fatty acids (FFA) were significantly (P << 0.05) higher in P compared with PROT 5 min after an STS. The calculated area under curve (AUC) of the serum insulin response during an STS was significantly (P < 0.001) higher in PROT compared with P. The EPOC value from 90 to 120 min after an STS was significantly greater in the PROT condition compared with P (P = 0.01), and PROT treatment had a significantly higher RER 2 h postexercise (P = 0.04). The AUC of serum FFA during STS correlated significantly and negatively with RER 10-30 min after STS (r = -0.53, P = 0.02).
Conclusions: Consuming 25 g of whey and caseinate proteins 30 min before an STS significantly decreases serum GH, testosterone, and FFA levels, and increases serum insulin during an STS. Furthermore, the pre-STS protein increased EPOC and RER significantly during 2-h recovery after STS.
Fatty acid oxidation is directly regulated by carbohydrate metabolism during exercise
E. F. Coyle, A. E. Jeukendrup, A. J. Wagenmakers and W. H. Saris
Department of Human Biology, University of Limburg, Maastricht, The Netherlands.
We determined whether increased glycolytic flux from hyperglycemia and hyperinsulinemia directly reduces fatty acid oxidation during exercise. Fatty acid oxidation rates were measured during constant-rate intravenous infusion of trace amounts of a long-chain fatty acid ([1-13C]palmitate; Pal) vs. a medium-chain fatty acid ([1-13C]octanoate; Oct). Six endurance-trained men cycled for 40 min at 50% of maximal O2 uptake 1) after an overnight fast ("fasting") and 2) after ingestion of 1.4 g/kg of glucose at 60 min and again 10 min before exercise (Glc). Glc caused hyperinsulinemia, a preexercise blood glucose of 6 mM, and a 34% reduction in total fat oxidation during exercise due to an approximately equal reduction in oxidation of plasma-free fatty acids (FFA) and intramuscular triglycerides (all P < 0.05). Oxidation of Pal was significantly reduced during Glc compared with fast (i.e., 70.0 +/- 4.1 vs. 86.0 +/- 1.9% of tracer infusion rate; P < 0.05). However, Glc had no effect on Oct oxidation, which is apparently not limited by mitochondrial transport. Furthermore, Glc reduced plasma FFA appearance 36% (P < 0.05), indicating a coordination of effects on adipose tissue and muscle. In summary, substrate oxidation during exercise can be regulated by increased glycolytic flux that is accompanied by a direct inhibition of long-chain fatty acid oxidation. These observations indicate that carbohydrate availability can directly regulate fat oxidation during exercise.
05-22-2006, 10:29 PM
Interesting info guys. So....given a hour intervals over a period of 4 weeks, which is most effect? Of course weight training is a given part of the regiment, but does the argument between Low Intensity Cardio, HIIT, and High Intensity cardio still remain?
HIIT is a great fat burning tool but it seems if your still increasing intensity by X amount to get into a 75% max workload wouldn' this mean you're body is still digging into burning CHO?
Also, it's known that long interval High Intensity cardio is the best of the best when it comes to fat burning but the worst when it comes to muscle preservation. So, what can we learn from all of this? should HIIT be avoided all together? Does that mean we should all stick to low intensity cardio?
All of our goals have one major concept in common, we all want to gain and preserve LBM and most of us are interested in long term quality gains. So, why even go on a big cut? Of course low intensity will take longer but if the study holds true, results should be considerably better.
05-22-2006, 10:42 PM
Thanks for the Study, LM. The study about fatty oxidation in correlation to CHO metabolism suggests that maybe morning cardio practiced at a low intensity may be optimal. It sounds like a meal before this may even hurt the process. In the past I've tried morning cardio with BCAAs, unfortunately I wasn't able to keep up the type of consistency to base any solid conclusions. Thoughts?
05-23-2006, 10:08 AM
these are great posts. However i wanted to ask one thing will this differ while "on" as opposed to off? I mean would being on help negate the catabolism of HIIT training?
05-23-2006, 10:25 AM
Yes now you are dealing with something different alltogether. Don't get me wrong, you are still going to be burning muscle doing high intensity stuff, you can't avoid that. However, the introduction of androgens into your system is going to increase protein anabolism, decrease serum cortisol levels, and have an overall anti-catabolic effect that will help you preserve muscle to a MUCH MUCH higher degree then when not cycling.Originally Posted by mixedup
I think the biggest debate in HIIT is the fact that you are doing a very small amount of it and the fact that there is a hormonal release with HIIT since it is mostly anaerobic, it is a lot like lifting, focusing on fast twitch fibers. It does increase overall metabolism throughout the day, moreso than does low intensity cardio. However, it seems that low intensity cardio is still the way to go overall.Originally Posted by Rage (SoCal)
I agree Rage, it does appear that morning cardio on an empty stomach could have implications. I am not sure how glycogen depleted you get from fasting overnight (sleeping), shouldn't be much. Insulin levels are also super low in the morning so that could help as well.
I am not saying this is definitely the way to go but seems logical?
05-23-2006, 10:57 AM
What about other supplements non hormonal such as cee and nos will that also help the muscle sparing effects
05-23-2006, 11:14 AM
I haven't found any scientific evidence to back up the CEE claim but I believe it definitely has an effect as creatine stores are the first to go, especially in HIIT. As for the No2 I have never been a fan and frankly don't really know all that much about it (I chose not to), so I couldn't tell you there. But yes supplementation can always help.Originally Posted by mixedup
05-23-2006, 11:34 AM
read the abstracts on protein ingestion immediately pre-workout. WHat about utilizing mega dose BCAAs around (pre, during, post) workout?
05-23-2006, 12:01 PM
Yeah BCAA's are a different story. I have found a lot of good studies in the past. I will post some later.Originally Posted by Max32
05-23-2006, 12:16 PM
I believe taking a small amount of very low GI carbs with some BCAA precardio to be the best way to preserve muscle mass. As a carb, I use the sugar alcohol xylitol.
MOTIV8 II Challenge
-=The Big Squirrel Nut Swingers=-
05-23-2006, 01:34 PM
Xylitol, interesting. I'll have to read more about that, I know it's used in certain gums and other products but never have I heard about supplmentation with it.
I think Utilizing BCAAs or even EEAs is a great tool. If one is on a budge, you could even opted for L-Leucine as it is also known to have muscle sparing effects.
Lake, you bring up a good logical point. The rate at which metabolism is slowed is quite high by the time you sleep, and of course during sleep metabolism is slowed even more, making glycogen storage not low enough to be a mojor problem unless of course exerting major demand from the body.
05-23-2006, 02:16 PM
AKA the F-buddy comes over haha. In that case guys you need to take ANOTHER PWO shake and I expect nothing less.Originally Posted by Rage (SoCal)
Not to mention that but you tell them you cannot have sex too close to eating as it will throw off your ability to burn more fat. If you are having sex a reasonable time after eating then you tell her to get on top because your Vo2 max cannot exceed 45%
05-23-2006, 02:54 PM
05-27-2006, 08:35 PM
So how did it go?Originally Posted by Rage (SoCal)
And I don't care what she said you are not getting a
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