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PED 291 - Chapter 17 NotesErgogenic aids consist of substances and procedures believed to improve physical work capacity, physiologic function, or athletic performance. There is always a research study out there about performance benefits from
The general population believes supplements improve physical appearance, so products marketed to reduce body fat and increase muscle mass become overnight best sellers. 5 ways as to how nutritional and pharmacological agents might enhance exercise performance: page 462 It’s ironic that the people who train hard, eat well, get treated for injuries would purposely ingest things that negatively affect their health. STEROIDSUsed medically for muscle wasting diseases, osteoporosis and breast cancer treatment. They work in a manner similar to testosterone by binding with special receptor sites on muscle and other tissues to contribute to secondary male sex characteristics. Stacking- combining oral and inject able steroids. Pyramiding- increasing dosages during 6-12 week cycles. Check out the cost of steroids…page 464, table 17.1. The most common reason people take them, to increase athletic performance. There is a great deal of confusion and variation about if anabolic steroids actually are effective. Negatives about steroids: (for males and females)
Androstenedione- an over the counter nutritional supplement naturally found in meat and extracts of some plants. Because it does not claim to offer any medical benefits the food and drug administration labeled it a food in 1994. Researchers claim it is one step away from testosterone because it aids the liver to make other active steroid hormones. It has not been proven, but the negative side effects listed above still do occur. Clenbuterol-a steroid substitute that body builders take before competition so that real steroids wont be detected in their blood. It is not approved for use in the U.S. Taking it leads once again to many of the side effects listed above. Human Growth Hormone- speeds tissue building processes and normal human growth. Specifically it:
It is used for children who has had kidney failure or may be HGH deficient and they cant grow. Athletes use it because it stimulates amino acid uptake and protein use by the muscle, while enhancing fat breakdown and conserving glycogen reserves. Because HGH occurs naturally in the body, there is not an accurate way to test for it as an ergogenic substance. It’s usually obtained by athletes on the black market. DHEA- weak steroid hormones made in the adrenal cortex from cholesterol. Called the mother hormone because when it’s produced by the body it surpasses all other known hormones. It’s even available as a chewing gum. The food and drug administration has no control over it’s distribution because it occurs naturally. It’s been called the super hormone. In 1994 it was changed and categorized as a dietary supplement for sale over the counter. There are many concerns about DHEA, including harmful effects on blood lipids, glucose tolerance, and tumor formation, especially on the prostate gland. Amphetamines- dangers on page 471. Caffeine is a controlled restricted drug in athletic competition. In the U.S. 75% of caffeine intake comes from coffee.
About 2.5 cups of coffee is below the International Olympic Committee and the NCAA acceptable limit. It works best at about 30-120 minutes after ingestion and leaves the body quickly-around 3 hours. Table 17.3, page 472 In all likelihood, the ergogenic effect of caffeine in high intensity, endurance exercise results from the facilitated use of fat as a fuel for exercise, sparing the body’s limited carbohydrate reserves of liver and muscle glycogen. When humans drink caffeine, 2 things probably happen:
Habitual caffeine users do not get consistent benefits. A caffeine using athlete should stop for 4-6 days before competition and then use it right before. WARNING- it’s a diuretic which causes unnecessary fluid loss. Alcohol-ethanol (a form of carbohydrate) provides 7 calories of energy per gram. Some argue that alcohol before competition reduces tension and anxiety (called the anxiolytic effect). Research does not substantiate any ergogenic effect of alcohol on muscular strength, or aerobic exercise performance. At worst, it impairs performance (ergolytic effect). Alcohol also enhances dehydration. It acts as a diuretic which places an athlete at great risk for heat injury. You see runners having a beer after a race, but alcohol affects rehydration because the more you drink means the more you urinate. Do not drink alcohol to warm up, it does not work because it is a vasodilator (less blood flows to tissues). Pangamic acid-vitamin B15. Those who use it claim that it increases the blood cellular efficiency to use oxygen, reduces blood lactate buildup, which would enhance endurance. It has been found to have no vitamin properties and serves no particular purpose to the body, and could be harmful. The food and drug administration prohibits it’s sale as a dietary supplement. Buffering solutions- increasing the body’s alkaline reserve (bicarbonate) before exercising by ingesting a solution of sodium bicarbonate or sodium citrate significantly improves anaerobic performance. One study had an elite 800 meter runner perform 3 seconds faster. Usually however, people will experience cramping and diarrhea an hour after ingestion. Glutamine- a non essential amino acid supposedly counteracts protein breakdown and muscle wasting, and may promote muscle glycogen accumulation in human muscle after recovery. All this is undergoing further study. Chromium- a trace mineral that potentially aids insulin function, which would put enable to transport more carbohydrate to the cells. Athletes use them to enhance fat burning and muscle building properties. They are one of the most hyped minerals in health and fitness. Most tests have shown that there is a small increase in fat free mass and a decrease in body mass, but no muscular strength increase. A downside is that chromium supplements affect iron transport and distribution in the body, and possibly damage chromosomes. The lack of iron would have a huge effect on our training regiments. Creatine- your body makes about 1 gram per day from non essential amino acids arginine, glycine, and methionine. The richest containing creatine containing foods occur in animal meats. 95% of the body’s total creatine exists in muscle. It’s sold as creatine monohydrate and comes in powder, tablet, capsule and liquid form. It can be purchased over the counter as a nutritional supplement. They recommend beginning dosages of 20-30 grams per day for 2 weeks, which increases muscle concentrations of creatine of up to 30%. Just about all ingested creatine becomes incorporated within the skeletal muscle. A little more than half combines with phosphate to make phosphocreatine (PCr). Type II fast twitch muscle fibers store about 4-6 times more PCr than ATP. Remember phosphocreatine (PCr) is the cells energy to provide rapid energy to remake ATP. PCr also shuttles inter muscle high energy phosphate between mitochondria and areas that initiate the action of muscle. This is important for activities that last up to 10 seconds, something that places significant demands on the remaking of ATP. Daily doses as low as 6 grams induce significant improvements in interval power performance (now research also says you can take as little as 2 per day, what your body makes). Creatine helps to replenish muscle creatine following heavy exercise, enabling someone to maintain high quality workouts. There is not a lot of information about long term effects of creatine supplementation on cardiac muscle and kidney function. As a nutritional supplement, creatine requires less stringent regulations because it’s not classified as a drug. It’s effects: There are marked improvements but more research is necessary in the areas of:
The loading phase: 20-30 grams daily in pill or powder form (cardiovascular people use it more in pill form). People who are vegetarians show the greatest increase in muscle creatine levels because they already have low levels in their diet. Maintainance phase: 2.5 grams daily Practical questions if you are using creatine:
Studies show when the person completely stops using it, the body’s creatine levels will return to normal in 35 days. 2 grams per day after loading will keep creatine in your system at increased levels. Figure 17.4, page 487 Caffeine blunts the ergogenic effect of creatine. PHYSIOLOGIC AGENTS Red blood cell infusion: blood doping How it works:
Benefits
figure 17.6, page 490 Does it work? figure 17.8, page 491 Erythropoietin- a hormone produced by the kidneys that stimulates bone marrow to produce red blood cells. This injection can be very dangerous because hematocrit can reach dangerous levels, and result in heart attack or stroke. Warm up-physiologic considerations are on page 492. Remember: warm muscles are more efficient than cold ones. Breathing in 100% oxygen during exercise extends endurance by increasing oxygen uptake, reduces blood lactate, and lowers breathing rate. Breathing in gas mixtures (hyperoxic) which is believed to improve the oxygen carrying capacity of blood, works during the activity, but provides no benefit before or after the workout. Figure 17.7, page 493. |
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