Sometimes I hear some females indeed complain " For boys it's much easier to loose weight etc. etc." after wich they continue to eat from their taco Bell.
Genetics and Testlevels do indeed play an important factor, but keep in mind that Bodybuilders conciously OVER-EAT in the off-season in order to get heavier (and hopefully a great deal of the added mass is muscle) while pre-contest they are challenged to strip of all the gained fat while preserving as much as muscle as possible... King Kamali balloons up to 300 pounds and looks like a beachball offseason, but on stage....BEWARE, cuts and seperation all over the place!!! (personally I am more into the Frank Zane look, waists of BB have become much bigger the last decade because of Growth Hormone causing the intestines to grow with pot belly as result, also a great deal of these broader waists is oblique and spinal eroctor muscle, because bb have been getting heavier overall, but I don't think that is particulary aestetic, Now Shawn Ray is a good exception, having a slightly smaller physique but everything in perfect proportion, the man puts statues of Greek Gods to shame)
Now that is at least as a challenging task as some female with obese genetics. Still they manage to do so, How ? Not by complaining, but by RELIGIOUSLY managing training, food and supplements, that means skipping the piece chocolate-cake you get offered at a birthday WHILE not skipping the pre-breakfast aerobic workout you had scheduled (granted, some pro's do eat junkfood off-season because they can afford that while using TEST/GH/INSULINE stack and dangerous diuretics and DNP/T3/Winstrol/Clenbuterol/ECA to look really ripped but still.....)
EFFORT & DEDICATION, EXERCISE!, GET PSYCHO! BURNING DESIRE, stick to it and you will get there!