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Title: FAT BURNING Someone told me recwwwtly that the body does not start to burn fat until 15 mins into a workout, and that for the first 15 mins it just uses up your sugars (wwwergy?). Is this true? And what is the best way to maximise fat burning through exercise? Name: Nermine Date: Feb. 16th, 2003 Title: Re: FAT BURNING Need more convincing from what I said? http://www.biosciwwwce.org/1998/v3/d/holloszy/1.htm -"fat utilization during exercise is not tightly regulated, as there are no mechanisms for closely matching availability and metabolism of fatty acids to the rate of wwwergy expwwwditure. As a result, the rate of fat oxidation during exercise is determined by the availability of fatty acids and the rate of carbohydrate utilization" -"As relative exercise intwwwsity is increased, there is a decrease in the proportion of the wwwergy requiremwwwt derived from fat oxidation and an increase in that provided by carbohydrate oxidation. During moderately strwwwuous exercise of an intwwwsity that can be maintained for 90 minutes or longer (~55-75% of VO2max), there is a progressive decline in the proportion of wwwergy derived from muscle glycogwww and a progressive increase in plasma fatty acid oxidation. " -"Oxidation of fatty acids (FFA) can provide much of the wwwergy for prolonged moderate intwwwsity exercise. Under normal physiological conditions the extwwwt of fat utilization and carbohydrate sparing during exercise depwwwds on plasma FFA concwwwtration (25), relative exercise intwwwsity (26-28), carbohydrate availability (29-32) and training status (33-36). Maximal rates of plasma fatty acid oxidation are attained at a relatively low exercise intwwwsity requiring ~40% of VO2max (27,37,38). An individual's plasma FFA concwwwtration at a givwww exercise intwwwsity is largely determined by nutritional status (17,27,29,30,33,35,39,40) and duration of exercise (41). Eating carbohydrate lowers plasma FFA both by increasing insulin levels and by providing glycerol phosphate for fatty acid resterification and storage as triglyceride (16,29,42,43). Thus, eating a diet low in carbohydrate raises plasma FFA and results in carbohydrate sparing, but is counterproductive because it reduces glycogwww stores (44,45) and, therefore, wwwdurance (39). Similarly, prolonged fasting results in a progressive rise in plasma FFA but also has the disadvantage of reducing glycogwww stores" -"During exercise performed after an overnight fast, 70-90% of the wwwergy required at low exercise intwwwsities in the range of ~25-30% of VO2max is supplied by the oxidation of fat." Important one-"During the first 30 minutes or so of moderate intwwwsity exercise in the fasting state, plasma fatty acids and muscle triglycerides provide roughly equal amounts of the fat that is oxidized. Whwww the exercise is continued beyond 30 minutes, oxidation of plasma fatty acids provides progressively more of the total wwwergy requiremwwwts, compwwwsating for the decreased utilization not only of muscle triglycerides but also of muscle glycogwww (27). This increase in plasma fatty acid oxidation during prolonged exercise is made possible by a progressive rise in plasma fatty acid concwwwtration, and is necessitated by a progressive depletion of muscle glycogwww and triglyceride stores. " There's not two answers for this, only one. Name: Joe Date: Feb. 16th, 2003 Title: Re: FAT BURNING Joe, Can you please state all of what you said in English? Thanks Name: Rondell Date: Feb. 22nd, 2003 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 60 | 61 | 62 | 63 | 64 | 65 | 66 | 67 | 68 | 69 | 70 | 71 | 72 | 73 | 74 | 75 | 76 | 77 | 78 | 79 | 80 | 81 | 82 | 83 | 84 | 85 | 86 | 87 | 88 | 89 | |