While tremendously beneficial to the cutting phase and often considered essential to competitive bodybuilders during contest prep, Trenbolone Acetate is also a phenomenal off-season bulking steroid . When we refer to this hormonal compound as versatile, that is truly an accurate statement. There are very few anabolic steroids that can promote mass like Trenbolone Acetate. More importantly, the effects of Trenbolone Acetate in this regard are not only strong but are far cleaner than most traditional bulking steroids. This hormone will not and cannot promote water retention, meaning each and every pound of weight gained due to use will be lean muscle mass. Of equal importance will be this steroid’s ability to help the individual control fat gain during a period of growth. To achieve true growth, this will require total caloric intake to be slightly above maintenance levels. How far above will vary from one man to the next, and while many often take it too far, this phase will still require a slight surplus. Unfortunately, this necessary surplus will promote body fat gains but due to the metabolic factors that surround Trenbolone Acetate they will be minimized. This is not a license to eat like there’s no end in sight, you can still gain a lot of fat if you continually gorge but you should be able to make better use of your total caloric intake. Those who supplement with Trenbolone Acetate during off-season periods of growth should gain less body fat than they would have without it.
Adverse effects of testosterone supplementation may include increased cardiovascular events (including strokes and heart attacks ) and deaths based on three peer-reviewed studies involving men taking testosterone replacement.  In addition, an increase of 30% in deaths and heart attacks in older men has been reported.  Due to an increased incidence of adverse cardiovascular events compared to a placebo group , a Testosterone in Older Men with Mobility Limitations (TOM) trial (a National Institute of Aging randomized trial) was halted early by the Data Safety and Monitoring Committee .  On January 31, 2014, reports of strokes , heart attacks , and deaths in men taking FDA-approved testosterone-replacement led the FDA to announce that it would be investigating the issue.  Later, in September 2014, the FDA announced, as a result of the "potential for adverse cardiovascular outcomes", a review of the appropriateness and safety of Testosterone Replacement Therapy (TRT).    The FDA now requires warnings in the drug labeling of all approved testosterone products regarding deep vein thrombosis and pulmonary embolism . 
Some bodybuilders and athletes use trenbolone esters for their muscle-building and otherwise performance-enhancing effects.  Such use is illegal in the United States and many other countries. The DEA classifies trenbolone and its esters as Schedule III controlled substances under the Controlled Substances Act .  Trenbolone is classified as a Schedule 4 drug in Canada  and a class C drug with no penalty for personal use or possession in the United Kingdom .  Use or possession of steroids without a prescription is a crime in Australia .