Remember, you canât out-exercise a bad diet so if youâre eating too many calories each day, it doesnât matter how much walking youâre doing since you will not be able to burn it all off. So, focus more of your attention on the foods youâre eating.
1 Keratosis pilaris causes numerous small, rough, tan or red little bumps around hair follicles on the upper arms, thighs, buttocks, and cheeks.  Keratosis pilaris creates the appearance of gooseflesh, goose bumps, or chicken skin.
Armpit Rash Causes. An armpit rash may be caused due to several different factors. Three of the most common causes of an armpit rash include friction, elevated heat and exposure to allergens. 1  The underarm skin is quite sensitive and can be easily irritated via friction. Heat rash is a condition caused due to elevated perspiration which results in the blockage of the sweat ducts occurring beneath the skin. 2  The sweat trapped under the skin then causes the formation of a bumpy armpit rash, which can occasionally be painful.