While we are familiar with the Propionate ester the remaining three esters that create Sustanon-250 are almost always found as part of a mixture or compounded anabolic androgenic steroid .
Developed by Organon, the original idea behind Sustanon-250 was to provide a testosterone form well-suited for hormone replacement therapy that would only needed to be administered once every few weeks and for all intense purposes the idea was a success. For the performance enhancing athlete Sustanon-250 can be a fine choice but the idea of injecting only once or twice a month is not applicable here. As a performance enhancer this testosterone like all forms will need to be administered on a more frequent basis. This mixture carries with it two fast, short esters, Propionate and Pheylpropionate, a longer more moderate ester Isocaproate and the very slow and long Decanoate ester. In order to keep testosterone levels stable and at their peak most athletes will inject Sustanon-250 at a minimum of every 3 days and more commonly every other day for optimal results.
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This is one reason why I think that carb cycling is good. You see eating enough protein, many carbs and many fats is the diet that is supposed to increase your testosterone and build muscle (combined with enough sleep). But such a diet is only possible when bulking. When cutting you need to either lower carbs or fats. Lowering carbs will make your workout performance suffer and lowering fats will make your testosterone levels suffer (maybe). So here is where carb cycling comes into play, when cutting. The days when you exercise you should follow high carbs and low fats but at the rest days – high fats low carbs. In general carb cycling is not necessary, but maybe it will help keep testosterone levels high while cutting.
10. Sleep and Fatigue . Inadequate testosterone can also lead to poor sleep quality, which means that the only thing you'll want to do under the covers is put your head on the pillow and crash. Testosteorne deficiencies decrease the all-important recuperative REM sleep and other critical sleep parameters. One study showed that low T did this not only by increasing weight gain, which negatively impacts sleep in and of itself, but also through other mechanisms that we do not yet understand.  And none of this should be a surprise considering how much that testosterone affects the brain.