How long do you think you could go without a shower?
This honestly depends on what I am doing. When I was in the military and doing training in the field, days could go by, because we just did not have the time to get that many people into the freezing cold showers. That, and I really did not want the headache I get after an ice cold shower.
I take showers after times of intense activity. Considering how often I am in Kickboxing and Tae Kwon Do, my showers are fairly frequent these days. Otherwise, my hair is even more difficult to deal with than when it is clean and sweat-free.
I do my best to shower before big events, such as family functions or events at the dojang. After all, I do not want to hear about any complaints through the grape vine later. I would prefer them to be major complaints and not over something as easily fixed as a shower.