Not only oxidative damage to every cell, to include a higher incident come a worsening of the symptoms of heart disease, catabolism of muscle and bone, and a shortened life-span through kidney or heart failure, all seem to be an inevitable consequence of regular long and ultra long distance sports.
Though antioxidants from a plant source seem to provide for only a very minimal protection, what might be the effect of introvenous glutathione, superoxidedismutase, and catalase on markers for oxidative and hydroxidative stress? - These are internally produced, and the bodies primary antioxidant defence.
The remaining question is to whether catabolism might be interrupted, perhaps through a high sugar and glutamic acid consumption during the event, and growth hormone inducers, such as GABA, taken before and after. Obviously kidney failure could be averted with adequate fluids on the person (regardless of the additional weight!)
Might be nice to make marathons healthy/healthier - there are also obviously benefits! As for ultra long distance nobody, unless perhaps they are cutting-edge scientists should be doing it for their health.
I had even been considering training for the Athens 1000 before all of the possible implications to health were known - Antioxidant supplements have unfortunately not lived up to all the earlier hype! I`ve actually only made reference to the worst of the side effects, and should probably have included certain forms of cancer(?) It might sound "young", at 56, to run 1000 miles, but is it really, if it means that you`re not around by the age of 70?
Is it not the case, with the numbers it concerns, that considerably more research is required in this whole area of long and ultra long distance sports