at 6'4 but only 86kg you likely don't eat much and/or don't have much of a base in regards to muscle also probably don't train and recover as well as you could. You should definitely hold off you won't see as good results as you could. I suggest fixing your diet to support your goal, do a lot more research and train natty for a few more years before considering to jump on. If you're at a plateau just eat more, sleep more or look at your training program and adjust it. Maybe you need more rest or alternate exercises. Just my opinion.
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