There are two types of piles (hemaroids) internal and external, they are caused by swolen veins in the internal and external sphincter (ringpiece) muscles, internal piles are the blue things that hang down outside the asshole like grapes and hurt like hell. It sounds as though you have an external pile from the external sphincter which look and feel like a pea under the skin and can appear anywhere around the asshole they are tender but not painful to touch.
Piles are a fact of life once you are over 30 wether you lift or not. They are caused by the very nature of sphincters because they have bad circulation due to the fact they never relax except when you are taking a dump, pressure from an approaching turd stimulates them to relax untill the pressure (turd) ceases and they contract again.
Any kind of excercise like cardio or stretching will improve the circlation and help alleviate piles, heavy squating while you have piles will certainly aggravate them. They never go away as such, the blood in the swolen vein will re absorb into the muscle and the vien will shrink to a tiny hard lump. Mostly they dissapear within a week or two. In severe cases of internal piles they can be surgicaly removed.
As there have been a lot of anal sex threads lately it may be worth noting that gentle presure from the opposite direction also has the effect of stimulating the sphincter to relax making entry easier on your lady/man.
