Overcoming cramps, inclement weather, etc., will not get you to heaven, overcoming sin will.
Thanks. I agree. But staying in bed instead of getting up for a morning run when it's raining or freezing or really hot takes some will to overcome the bodily urge of remaining in bed. And overcoming bodily urges is a valuable skill which certainly can help get us into heaven.
Three of the seven deadly sins are directly related to the body - lust, gluttony, and sloth - and I think there's an argument to be made for anger as well. In other words, if you spend your life doing only what your body is telling you to do, your chance of getting into heaven is seriously diminished.