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.
Causes of Stretch Marks on Arms. Stretch marks on the arms are most usually caused by muscle gain, weight gain and puberty. Gym buffs who spend hours in the gym lifting weights are the most vulnerable to getting stretch marks in the arms.