Written by Team MD
14 December 2017

15NN119-NUTRITION

Seven Nutrition Facts to Boost Your Gym Work

 

 

1) Leucine + Protein Better Than Protein Alone

 Leucine is a key amino acid for stimulating muscle protein synthesis. In addition to supplying protein building blocks, leucine is a signaling chemical that triggers a protein synthesis pathway called mTOR. Protein high in leucine triggers protein synthesis, even in the absence of muscle tension and exercise. This is particularly important in older adults, who lose muscle mass with age and are typically inactive. The maximum beneficial amount of protein in a single meal for promoting muscle protein synthesis is 20 to 30 grams. A study from Maastricht University in the Netherlands found that a meal containing 20 grams of protein supplemented with 2.5 grams of leucine increased muscle protein synthesis more than protein alone in aging men (74 years old). This was a sophisticated study using isotope tracers. These results might not apply to young, healthy bodybuilders. (Clinical Nutrition, 32: 412-419, 2013)

2) Increased Protein Intake Important During Weight Loss

 Metabolic rate and muscle mass both decrease during weight loss. This makes it difficult to maintain lost weight. A study from Maastricht University in the Netherlands found that protein intake was critical during weight loss for maintaining normal metabolism. Overweight adults aged 18 to 80 consumed a low-calorie diet for six months. Half of the people consumed 0.8 grams of protein per kilogram of bodyweight per day (normal protein intake) and half consumed 1.2 grams per kilogram of bodyweight per day (high protein intake). After six months, lean mass and metabolic rate was highest and diastolic blood pressure was lowest in the high-protein group. Increase protein intake when trying to lose weight. (Journal of Nutrition, 143: 591-596, 2013)

3) Creatine Decreases Glycogen and Muscle Protein Breakdown

 Creatine monohydrate is a proven supplement for increasing muscle mass and strength. It has also been used to treat diseases that cause neuromuscular degeneration such as Lou Gehrig’s disease, arthritis and Parkinson’s disease. Creatine helps athletes recover from training and competition. A study from Taiwan showed that supplementing creatine for 15 days (12 grams per day) decreased chemical markers of protein breakdown and increased muscle glycogen levels. One possible problem was that creatine supplements increased markers of tendon breakdown. Creatine promotes sports performance and speeds recovery. (European Journal of Nutrition, published online February 8, 2013)

4) Burgers Save the Buffalo

Buffalo meat is a better dietary choice than beef because it is lower in fat and contains heart-healthy omega-3 fatty acids. Buffalo meat contains one-third fewer calories than beef and 75 percent less fat. Wanton slaughter of the animals as part of the fur trade by buffalo hunters like Wild Bill Hickok, Buffalo Bill Cody and Wyatt Earp and by railroad workers for food almost drove the animals to extinction by 1880. Today, buffalo number more than 500,000, with herd sizes increasing because of the popularity of the meat. Environmentalists are pleased with the popularity of buffalo meat because the animal is once again thriving. Ironically, the buffalo are back because people want to eat them. Buffalo meat is a good protein for bodybuilders because it is low in fat and high in protein. Buffalo meat tastes best when cooked medium rare.

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(Nutrition Research, 33: 293-302, 2013)

 5) L-Carnitine Linked to Increased Risk of Heart Disease

 Nutrition experts recommend reducing intake of red meat in the diet because it is high in cholesterol and saturated fat, which promotes coronary artery disease. A Cleveland Clinic study led by Stanley Hazen found that carnitine, a popular athletic supplement and component of red meat, also triggers heart disease. Bacteria in the gut break down carnitine to trimethylamine-N-oxide (TMAO), which promotes arterial disease by increasing cholesterol deposits in the arteries. High TMAO in the blood was a good predictor of heart attack and stroke. A study by the same research group showed that gut microbes also metabolized phosphatidylcholine, another athletic supplement, to TMOA. Administration of antibiotics decreased TMOA levels. Carnitine is a popular athletic supplement. However, a joint position statement from the American Dietetic Association and the Dietitians of Canada concluded that carnitine does not improve athletic performance. It might also promote heart disease. Further research is warranted. (Nature Medicine, 19:576-585, 2013; New England Journal of Medicine, 368: 1575-1584, 2013)

6) Glycomacropeptide Promotes Fat Loss

 Glycomacropeptide (GMP) is a whey protein peptide made from casein. GMP may promote weight control by stimulating the release of cholecystokinin (a gut hormone that regulates appetite and satiety) and supporting beneficial intestinal bacteria that prevent obesity. A Chinese study on rats showed that animals fed GMP and a high-fat diet showed reduced fat growth and reduced fatty acid synthesis compared to control animals. GMP can help reverse the effects of a high-fat diet. (Food and Chemical Toxicology, 56: 1-7, 2013)

7) Glycemic Index is a Valid Measure of Carbohydrate Quality

Many nutrition experts have put more emphasis on whole grains and fiber for high-quality diets than on glycemic index. Thomas Wolever from the University of Toronto argued that glycemic index is an important measure of carbohydrate quality and should be emphasized as much as whole grains and fiber. Glycemic index is the rate that a food increases blood sugar. Several popular diets promote low glycemic index foods for weight control. The thinking is that rapid increases in blood sugar stimulate insulin release, which causes a crash in blood sugar and increases hunger. Low glycemic index foods are also good for endurance training because they provide more sustained release of sugar into the blood. Glycemic index should be part of the dietary recommendations of healthy adults. (European Journal of Clinical Nutrition, 67: 522-531, 2013)

 

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