what does chemistry have to do with muscle fatigue?
89868
That's an excellent explanation!  \nYes, when your muscle cells are worked out, they need to produce a lot of energy, and they usually use oxygen and a process called aerobic (meaning that it uses oxygen) cellular respiration to get that energy from the energy molecule, ATP, which stands for adenosine triphosphate.  However, when you need that much energy, your oxygen supply runs short, so to convert ATP to ADP (adenosine diphosphate) and release energy, your body has to use an alternate form of cellular respiration called lactic acid fermentation.  Lactic acid fermentation is a form of anaerobic respiration because it doesn't use oxygen.  It's not as efficient as normal aerobic respiration.  It also forms lactic acid, which is the chemical that causes the sensation of muscle fatigue.
783158
cardio and workouts help, but at the end of the day, lactic acid builds up fast during high intensity exertion, and that causes the burn that wears on your will power, and your ATP is depleted beyond the muscles ability to replace it. then you run out of energy.\n\nlong  and paced exercise does different things to you physically than   fast and erratic.
620112
...stamina and fatigue i guess
319336
Acid??? during intense use of muscles, oxygen becomes short in supply compared to demand. When that happens, the metabolism swithes to anerobic and the waste product is NOT \nCO2, but lactic acid. Lactic acid builds up within the muscles, and being a waste product, is a minor poison to the muscles. The muscles react by becoming sore. In anerboic metabolism, the energy conversion for carbs to energy is greatly reduced. Therefore, you will notice a tiring effect as you get farther into the excercising.
448081
twitching of muscles may be due to changes in the level of chemicals in blood especially calcium, also magnesium etc.\nIf the condition persits pls see a doctor, who might get a blood chemistry done.
623084
Myalgic Encephalomyelitis, also known as Chronic fatigue syndrome (CFS).
679555
By all means see a doctor. Chronic fatigue can be a sign of many things.  Including diabetes, thyroid, mono, anemia, depression, poor diet, stress, even a hormonal imbalance.  Just to name some.  More then likely your Dr. will get you back on track after a simple blood test.  Good luck to you.
713796
Yes, I think it has to do with endorphines and other chemicals that your body releases. I feel the same way after a workout.
571737
Simple, muscle fatiguing. Lift what feels like a bit of a strain but not much. This is your lean muscle grade. Now lift 25% more than this range--this will "fatigue" your muscles and cause them to set up for more work, ie bulking up. Of course, eat an hour after this strenuous workout to replenish the muscles with the loss of glutamine that will occur. YOu should see results in just two weeks!
49116
A deficiency in potassium and other salts can also lead to severe muscle contractions. Also hydrate regularly. Is this due to athletic workouts?
489546
Protiens are the building blocks of your muscles. When you work out, your actually making little tiny tears in your mucles and that's what makes them ache when you're done and also why they seem a little bigger and harder immediatly after you've finished. Protiens are used by your body to "heal" the little tears by filling them in with more muscle tissue and that is how you build larger mucles.\n\nWhen you're finished a hard work out, drinking a protien shake will give your body plenty of what it needs to heal your muscles faster, and you wont experience sore, achey mucsles the next day.
789940
There is a popular misconception that muscles are 'broken down' by the lactic acid that builds up during exercise, but this isn't quite true.  Lactate will indeed build up to high levels in the muscle, but not lactic acid.  The reason why acidosis may occur in muscles after strenuous exercise (leading to fatigue and then later soreness) is because of the protons that build up when ATP is hydrolysed.  This will cause some damage to the muscle fibrils (within the muscle cell), and when they recover they will be replaced with greater numbers.  Note, there is no increase in the amount of muscle cells, the muscle cells just get bigger.
1174109
Creatine and amino acids serve different purposes.  I don't take amino acid supplementation, so I haven't done much research on it, but I am taking creatine and have done a lot of reading on it.\n\nCreatine is a natural substance that you obtain from your diet and can make yourself.  Creatine's primary purpose in weightlifting is to replenish ATP stores during intense activity.  By taking creatine supplementation you can increase your creatine stores by up to 40% (depending on how much you are already getting in your diet).  This will allow you to work out harder longer and get better results from your training.\n\nCreatine is also known to cause cell volumization, as it causes the muscles to hold more water.  Note that this is different the water retention, as water retention is when water is retained on the outside of the cells, causing the muscles to lose definition and look smoother.  Cell volumization pulls the water into the cells and causes the muscles to look harder.\n\nThere are also studies that have come to light recently that show that cell volumization can make protein synthesis more productive.  In theory this could mean that creatine could directly help you build muscle, but more research needs to be done to prove this effect.\n\nCreatine is also a very safe substance to supplement.  While there are rumors of some side effects, such as muscle cramping, kidney problems, etc, no studies have actually proved these to be actual risks.  One possible risk is the down regulation of the creatine transporters due to oversupplementation, but if you follow the recommended guidelines you shouldn't have to worry about that effect.  To be safe you should actually take less creatine than most manufacturers recommend, though.  Studies have shown that your body can absorb a lot less than most companies suggest you take anyway.  They have found that your body is unable to absorb more than 3-5 grams of creatine per day after you have finished loading.  To top that off, after working out you are capable of absorbing up to 10% more than your normal maximum capacitiy.  They estamate that you only use 3% of your creatine stores when you don't work out.  That means that if you are fully loaded and then take creatine after working out you will have more creatine than you body can obsorb for the next 3-4 days or until you work out again.  Bottom line: after loading it is only necessary to take creatine after working out.  I only take about 5 grams after I work out to replenish the creatine I have used.\n\nAs far as amino acids go, do some research and see what the benefits are to you.  I've already found an article that proved to me that glutamine is a waste of money, but I haven't researced any of the other availlable products.
335323
fa·tigue   Audio pronunciation of "fatigue" ( P )  Pronunciation Key  (f-tg)\nn.\n\n   1. Physical or mental weariness resulting from exertion.\n   2. Something, such as tiring effort or activity, that causes weariness: the fatigue of a long hike.\n   3. Physiology. The decreased capacity or complete inability of an organism, an organ, or a part to function normally because of excessive stimulation or prolonged exertion.\n   4. The weakening or failure of a material, such as metal or wood, resulting from prolonged stress.\n   5.\n         1. Manual or menial labor, such as barracks cleaning, assigned to soldiers.\n         2. fatigues Clothing worn by military personnel for labor or for field duty.
391950
Stamina would have to do with availability of oxygen or anaerobic fuel (such as glucose, pyruvate, creatine phosphate, etc)- Thus a pill that could increase delivery of these to muscle would work, or one that caused more rapid regeneration of depleted energy stores-  Also anything that would cause breakdown of lactic acid into an inert or non-toxic form would aid stamina.
713832
It is caused by lactic acid build up, and sometimes by tetany (insufficient calcium in the muscle tissue). I suggest an increase of calcium in your diet. Sugar provides only energy as do the carbohydrates (complex carohydrates are slower in providing energy but better long term). Try the calcium.
224495
Primarily by two actions:\n1) Increase hemoglobin, which acts indirectly to allow your muscles to avoid anaerobic activity.  This isn't a change in the muscle (it's a change in your blood) but it has an effect on perceived fatigue.  it's part of "getting in shape"\n\n2) Grow.  Muscles will increase in size in response to stress.  That's how weightlifting works.  They can also change somewhat from fast, weak, fibers towards slow, stronger, fibers (and back again) depending on stimulus.