-am I at a disadvantage if I don't use PED's-
Yes, you are. Its obvious, that your body cant produce so much energy and power to beat your goals, and its getting tired by the time, so it needs "extra"help. As my coach said- Best PED is fitness, run 5 miles every day and you will have enough power to stand 15 mins intensive round.
Personally, Im using bodybuilders stuff as- BCAA(muscules&streingth), Whey protein, Anabolic Nitro X and L-Glutaminne