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| Blood glucose alone would not last for 90s of running up the stairs. |
80 minutes! That's the SuppVersity Figure of the Week and the impressive timespan you could (theoretically) fuel your energy demands during exercise at 70% of your VO2max from your muscle glycogen stores.The latter hold the energetic equivalent of ~1,500kcal and are thus an almost 40x larger reservoir of energy than the tiny amounts of glucose that's floating around in your bloodstream (data based on Gleeson. 2008).
If you had to rely on that alone, you would pass out after 2 mins of the previously mentioned exercise at 70% VO2max.
Obviously no workout is going to be fueled 100% exclusively by glucose/glycogen, so that you can still use the amount of energy your body stores in the fat cells (~93,000kcal) and in form of tissue proteins (~49,000kcal) and keep running for another 7,400 minutes or 5.13 days... theoretically
Enough of the figures let's get to some recent research results
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| You want the boost without the buzz? Hit the right taurine / caffeine ratio to avoid the stim crash & sleeplessness (learn how) |
Taurine for increased strength and recovery during and after eccentric biceps curls (Acordi da Silva. 2013) In a recent study researchers were able to show that the provision of taurine for 14 days before a standardized eccentric exercise regimen comprising 3 sets of eccentric biceps curls on the Scott bench that were performed at 80% of the 1-RM to total failure resulted in significant increases in strength levels and thiol total content of the muscle, as well as a decrease in muscle soreness, lactate dehydrogenase level, creatine kinase activity and oxidative damage (xylenol and protein carbonyl) after the workouts.
Since the activity of the antioxidant enzymes (superoxide dismutase, catalase, and gluthatione peroxidase) and inflammatory markers (tumor necrosis factor, interleukin (IL) -1 beta, and IL10) in the blood of the twenty-one participants (mean age of 21 ± 6 years, weight of 78.2 ± 5 kg) were not altered, decreases in muscle growth as they have been reported for NAC, only recently are not likely to occur.
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| CLA in pomegranate? Not really, but the CLnA in the seeds of the fruit may be even more potent (learn more) |
NAC increases fat oxidation, but compromises performance during HIIT cycling (Trewin. 2013) Talking about NAC another recent study conducted by Adam J. Trewin, Aaron C. Petersen, Francois Billaut, Leon R. McQuade, Bernie V. McInerney, Nigel K. Stepto found that the provision of N-acetylcysteine (NAC) before a HIIT cycling exercise (6x5min HIIE bouts at 82 % PPO (316 ± 40 W) ) separated by 1min at 100W, then after 2min recovery at 100W) elevated the fat oxidation yet only during the last two bouts by 150%. It also reduced the makers of lipid oxidation (these are cell lipids not stored fat) and lactate levels after the time trial. However, the mean EMG activity was -7% and the mean power output 4.9% lower during the NAC trial.
Now, whether that's a good or bad thing actually depends on your goals. If you are glucose tolerant and train to burn fat, it's a good thing. If you want to empty your glycogen stores to promote GLUT-4 or are a competing athlete whose main interest is maximal performance, though the changes would be detrimental.
- Exercise training vs. dieting - anti- vs. pro-inflammation (Auerbach. 2013) In a soon-to-be-published paper in the American journal of physiology. Regulatory, integrative and comparative physiology scientists from the University of Copenhagen report that contrary to their own expectations, the adherence to an endurance exercise program that would burn ~600kcal /day (LISS training of 65% of the heart rate reserve) that was interspersed by 3-4 days of high intensity workouts at 85% of the heart rate reserve ...
"[...] increased the number of anti-inflammatory CD163+ macrophages (from 12.7 [2.1] (mean [SE]) to 16.1 [3.1] CD163+ cells/100 adipocytes, P=0.013), whereas diet-induced weight loss tended to decrease CD68+ macrophages in subcutaneous abdominal adipose tissue" (Auerbach. 2013)
In that it is interesting to note that the most beneficial changes were observed in the group that compensated for the 600kcal extra energy expenditure per week. ![]() |
| Figure 1: Effects of the 12 week diet + exercise / diet only / exercise only interventions on the body composition of caucasian overweight men aged 20-40 yrs w/ body fat >25% (Auerbach. 2013) |
Compared to the exercise + baseline diet and diet only (-600kcal energy reduction) group, they had a highly significant decrease in the TNF-alpha in the femoral adipose tissue ended and the greatest increase in anti-inflammatory CD163+ macrophage.
- Carnitine rescues fast-twitch glycolytic macrofibers in a rodent study (Couturier. 2013) According to a recently published paper in Nutrition & Metabolism, the provision of carnitine as part of the diet did prevent the type-II-diabetes-induced transition of glycolytic to oxidative muscle fibers in obese Zucker rats.
Now while you can never be sure if things that happen in a rodent model will also happen in man, it is not totally unlikely that these effects could be observed in human beings as well.
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| Carnitine to prevent sugary fat gain |
"The results demonstrate that carnitine supplementation to obese Zucker a rat counteracts the obesity-induced muscle fiber transition and restores the muscle oxidative metabolic phenotype. Carnitine supplementation is supposed to be beneficial for the treatment of elevated levels of plasma lipids during obesity or diabetes. " (Couturier. 2013)
The corresponding human equivalent dose to the 3g/kg of carnitine in the rodent chow would be would be roughly 16mg/kg or something between 1-2g per day for an adult human being (learn how to calculate HEDs). This is actually not really much and may well be worth a try, assuming that your own or your relatives' glucose burning, weight lifting musculature is endangered by diabetes.
That's it for the short news!
In case you still have enough glycogen left in any of your major "tanks", or, alternatively, are depleted enough to have your body produce tons of ketones to fuel your brain for another 3-5 minutes you may yet want to take a brief look at the latest
SuppVersity Facebook News...
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| With the relation of fish oil to prostate cancer (see facebook news) being based on high serum levels, I suggest you (re-)read this post about why fish oil supplements may fail to increase tissue levels, of way which previous studies have shown that they may protect against prostate cancer (read more). |
High or low fat for blood lipids? - Recent meta-analysis says: "The jury is still out there."The same appears to be the case for the type of fat, by the way | read more...- Fish oil is bad for your prostate! - That's at least what the latest spin-off of the SELECT study (the one with selenium and vitamin E, you know?) says | read more...
- Green tea, butter and bread - Neither the most nutritious, nor the most yummy breakfast one can thing of, but way better for your triglyceride levels than water, butter and bread | learn why....
- Fat gains with saturated fats? Not if you pick the right ones - Study identifies interestification of saturated fat as a main determinant of its obesogenic effect. Regular palm oil, for example leads to lower fat gains than soy oil | read more...
... before you either eat, train sleep or have fun on the best day of the weekend:
Saturday! ... What's so special about Saturday? Well easy, you can sleep late, shop, work out, party and whatever you like and sleep all the exertions and occasional "spiritual diversions" off on Sunday ;-)
References:- Acordi da Silva et al. Effects of taurine supplementation following eccentric exercise in young adults. Applied Physiology, Nutrition, and Metabolism. 2013
- Auerbach P, Nordby P, Bendtsen LQ, Mehlsen JL, Basnet SK, Vestergaard H, Ploug T, Stallknecht BM. Differential effects of endurance training and weight loss on plasma adiponectin multimers and adipose tissue macrophages in younger, moderately overweight men. Am J Physiol Regul Integr Comp Physiol. 2013 Jul 10. [Epub ahead of print]
- Couturier A, Ringseis R, Mooren FC, Krüger K, Most E, Eder K. Carnitine supplementation to obese Zucker rats prevents obesity-induced type II to type I muscle fiber transition and favors an oxidative phenotype of skeletal muscle. Nutr Metab (Lond). 2013 Jul 10;10(1):48.
- Trewin et al. N-acetylcysteine alters substrate metabolism during high-intensity cycle exercise in well-trained humans. Applied Physiology, Nutrition, and Metabolism. 2013
- Gleeson, M. Biochemestry of Exercise in Maughan, Ronald J., ed. The Encyclopaedia of Sports Medicine An IOC Medical Commission Publication, Nutrition in Sport. Vol. 7. Wiley.com. 2008.
