I have been thinking about this one for a while. Especially on laundry days. Which lately, with the advent of colder temperatures and thicker clothes, has been almost every day. I usually exercise six days a week, early in the morning - if I'm lucky (my kids are eeaarrrlyy risers)- before the kids are awake. My husband runs three to four days a week as well. So now that I've set the groundwork we can examine if exercise is bad for the environment.
I can't speak for others, but when I exercise, especially when I run, I sweat and it's not pretty. So, before 6:30am I have dirtied my first pair of clothing for the day. If my husband has run too, ditto for him. Our girls participate in an hour long gymnastics class once a week and they, you guessed it, get sweaty. So, once a week they wear clothes - sweats, shorts and leotards, for one hour, which must then be washed. I have inadvertently made an environmentally conscious effort by changing my exercise time from the girls' nap time to before they wake up in the morning so now I only have to shower once a day rather than twice. But still, when I think about all of the extra sweaty laundry that would not exist if we did not exercise and the occasional extra showers and baths that are taken to "freshen up", I wonder about my impact on the environment?
It's probably not as bad as I imagine, we do now at least have a high efficiency washer and dryer. Limiting myself to one shower a day conserves water as well. Not smelling fresh is not an option so any amount of showers or cleaning products which are necessary to ensure this are justified for my own and others' olfactory satisfaction.
I think I'm just fed up with laundry :)