Wednesday, December 2, 2009

Fitness of the body & mind - Part II(Anaerobic Glycolysis)

Note: In the previous article, I mentioned that a Physician purposely let B Lymphocytes circulate in the bloodstream in some cases of Bone Marrow Transplantation. Let me correct myself by writing precisely it is the "Hematologist"(as Physician is a general word), who deals with the disorders/diseases of the blood.

Energy production of ATP synthesis can occur through either anaerobic or aerobic glycolysis. We will see in this article how anaerobic metabolism is carried out in our body. Our body depends on oxygen to carry out many chemical reactions inside our body. Aerobic means "dependent" on oxygen. Instead of using "presence" and "absence" of oxygen, which can convey a wrong message, I like to use "dependent" and "independent" of oxygen. So, anaerobic means, the body doesn't depend on oxygen to carry out the chemical reactions.

Carbohydrate metabolism(anaerobic/glycogen) is much more efficient & faster than the fat metabolism. You will understand this better when you see the details of the pathways in aerobic as well as anaerobic metabolism and the relative performance of these two reactions in sprinters and marathoners. To put it in a different way, anaerobic metabolism(sprinters,high jumpers,weight lifters)means "short intervals, high speed" and aerobic metabolism(marathoners) means "longer intervals, low/reduced speed". Any exercise that persists for more than roughly 3 minutes must be powered by aerobic metabolism.

There are two ways in which a cell can harvest energy from food:(1)Fermentation and (2) Cellular respiration. The first process/step, irrespective of aerobic or anaerobic metabolism is "glycolysis". Glycolysis is the breakdown of glucose(C6H12O6) into two pyruvates(C3H6O3). That means, the 6-carbon glucose splits into 2 3-carbon pyruvic acid. Glycolysis takes place in the cytoplasm of the cells. This pyruvate is broken down differently in aerobic and anaerobic reactions.

Anaerobic metabolism/Fermentation: These pyruvic acid molecules are turned into some waste products and very little energy(ATP). Actually 4 ATP molecules are produced but 2 are used up in the process. It is similar to: our body needs calories/energy to even eat/consume calories. So, in this process only 2 ATPs are produced. There are 2 types of fermentation:

(i) Lactic acid fermentation: This is done by some fungi or some bacteria like lactobacillus acidophillus found in yogurt and sometimes by our muscles(in the case of sprinters). Normally our muscles, like any other body part, do cellular respiration/aerobic using oxygen supplied by the lungs and blood. However, under greater exertion(like sprint), when the oxygen supplied by the lungs and blood can't get there fast enough to keep up with the muscle's needs, our muscles can switch over to lactic acid fermentation. In lactic acid fermentation process,the 3-carbon pyruvic acid molecules are converted to lactic acid. It is the presence of lactic acid in the yogurt that gives it sour taste and its the same lactic acid in the muscles that makes them so sore and stiff the next day. Once our muscles form lactic acid, they can't do anything else with it, until it is washed away by the bloodstream and carried to the liver which is then able to get rid of the waste(Remember liver's duty is to remove toxins/wastes from our body?). To reduce the acidity(soreness/stiffness), drink plenty of water with a total of 1/4-1/2 teaspoon of sodium-bi-carbonate popularly known as Baking Soda, NaHCO3. Baking soda is alkaline, so it will neutralize the acidity building up due to fermentation.

(ii) Alcohol fermentation:This is done by some yeast(used in bread, pizza dough, beer,wine!) and some bacteria. The waste products are ethanol and carbon-dioxide. In bread making, it is the CO2 that forms and gets trapped between the gluten(long protein in wheat)molecules that causes the bread to rise and the ethanol evaporating gives it a wonderful smell! Many college students and regular boozers are very familiar and probably expert(!) with the effects of ethanol in beer and wine...

4 comments:

Suresh.N.C. said...

Very useful and informative again.. there is a lot of technical stuff in here, which you have explained very effectively for lay readers.... some pictures inserted within the text (I don't know if this possible) will help readability even more..

Nappinnai NC said...

Thank you very much Suresh, I will try to include pictures...You want me to put atoms circulating etc.....?

See for example, the aerobic glycolysis(which I will post within next couple of days) chemical reactions with formulas may throw the reader to lose interest! That's why I'm not going to include. But definitely, when I talk about food and how food is digested by going through different body parts, I will include the human body parts to explain it in simpler terms.

Suresh.N.C. said...

BTW, I started exercising regularly since last 5 months.. I walk / jog for 2 miles on the treadmill every single day...

Nappinnai NC said...

Great. Body is meant for exercise whether we are on land or space. Astronauts develop temporary osteoporosis right after their space trip. Latest space shuttles include equipments that can help astronauts do some exercise involving normal impact on the lower part of the leg.

I do jump rop within the house and also try to walk in this damn Florida winter!

Walking is good for endurance. But if you want some shape/curve to your body, you have to do strengthening exercises like free weights, push-ups. You will burn a lot with push-ups. You should make it a part of your life. Not only does it tone the upper body but also strengthens the knees and feet.