Yes absolutely. When I used to exercise without juices and supplements, I would get sick and run down. Rigorous exercise creates free radicals so you have to counteract them. http://www.findarticles.com/p/articles/mi_m0FKA/is_n1_v59/ai_18992514
I find that taking l-carnosine which is ONLY found in meat at about 1,000 to 2,000mg if I am engaging in heavy exercise, plus 1,000mg of vitamin C esterised C which my body doesn't pee out, l-glutamine 1,000 mg and a lot of water with a super greenfood. I hardly get post workout muscle strain. After a run, I drink a lot of green/red stuff from Gary Null and I don't get the leg pain I used to get. I'm very sophisticated about my workouts now.
Before I go to work, I also drink a green beverage and cayenne pepper pills. I never get sick when I do this. The body is a dynamic machine and I do what I can to keep it running and in good form.