Does taking vitamin C before a race such as a 8k improve preformane? I have a teamate that does this, he thinks it help oxyginate (sp) his blood. He also said weight lifters do it, but I've never heard of anything like that. I know taking vitamin C before a race couldn't hurt (it's onyl a vitamin) Also, are there any other natural vitamins that taken before a race will help improve preformance.