I would consider myself to be very athletic. Iv been lifting for about three years or so and lift weights on average about 5/6 days week, as far as cardio goes, i am currently doing two sessions of HIIT to help burn fat along with two steady state sessions of cardio to maximize my fat loss. I'm in a deficit eating around 1550 calories, about 110 carb, 130 protein and 60 fat. I follow a IIFYM diet, therefore i eat 90 percent clean and have the occasional treat as long as it fits within my macro nutrient intake. I'm just looking to shred through the next upcoming months to then go into a lean bulk phase and put on some size in hopes of possibly competing for a show in future. I'm considering taking S4 50 mg day ,GW-510516 20 mg day and mk-2866 25 mg day. Would this be a could stack to start off? Any more suggestions are welcomed, thank you!