You should take protein and creatine as your key supplements or a Weight Gainer product if you want to gain maximum mass. Take a whey protein shake 2 to 3 times per day with one serving being just before your Halo immediately after training and take creatine monohydrate powder or a creatine tablet (like Creakic or Creadex). Start off taking 4 servings per day for the first 5 days and thereafter take 1 to 2 servings per day (2 on training days and 1 on non-training days). To gain mass at the fastest rate, you can either do the Nitro/Cell stack (Nitro 3 times per day and Cell-Tech twice on training days and once on non-training days - always take one serving of Nitro immediately, followed by Cell-Tech right after training) OR you can use a weight gainer like Mutant Mass (along with powdered creatine) or Mass-Tech or Muscle Fuel Anabolic (which already contain creatine). If your diet is good (high in calories and protein), go with the Nitro/Cell stack, if your diet isn't so good, go with one of the mass gainers - start off with 2 to 3 scoops twice daily and increase until you are gaining the desired amount of weight per week (1/2 to 2 kilos).
If you are looking to put size on try a program called P90X. The program is very intense and even caters towards athletics. Cuation, this program is extreme but works wonders…I started at 175 lbs and 22% body fat at 5’″ at 26yrs old and know down to 17% body fat after only 3 months. They even suggest what foods to eat and how much depending on what you want to do. The programs are brole down into toning, weight lose, and building muscle mass. The program is a little high priced but real worth it. I take creatine with my workout and seemed to do wonders. As far as speciallized workout for football, I have a very close friend who has been a varsity coach for 10+ years and said he has never seen anything like this program…….he started making his players do it in the off season and plans to set something up for summer workouts…..trust me, this program will give you great results!!!