Summary of 2010 report on marathons and the heart. Less fit runners can do significant damage to the heart i.e. fibrosis compared to fit runners. V02 max is a good way to assess aerobic endurance and differentiate between the two. Dr Larose showed via MRI that it can take 3 months for the heart to recover.
Runners have a 30% lower all-cause mortality and a 45% cardiovascular mortality compared to non-runners in study. What is interesting, is that only 5-10 minutes a day at very slow speeds is all that is required to receive these benefits. As other studies have now shown, more is not necessarily better.
No cases of hyponatremia noted in marathon runners. Of note, over hydration was prevented through limited stations enroute. NSAIDS negatively altered renal function
The majority of ultra marathon runners deal with hypernatremia versus hyponatremia. The majority were normonatremic. Intravenous fluids can more rapidly resolve hypernatremia versus oral liquids and serves as useful means to reduce hypernatremia when oral liquids proves intolerable.
Again, a study points to a "U" shaped curve in health benefits from jogging. This study used pace, duration, and frequency and found that 2-3 x/week at slow pace provided the best health benefits compared to the moderate and strenuous runners.
This study shows that "healthy marathon" runners may not be as healthy as once thought. Basically, current strategies to assess coronary artery calcification is inadequate. Point: damage is being done that is not being detected.
For endurance athletes, low carb and high fat diet utilizes the high fat oxidation in these athletes compared to a high carb diet. Glycogen stores did not differ between the two groups.
full study of previous abstract: low carb and high fat diet found to maintain muscle glycogen equal to high carb diet in endurance athletes. Endurance athletes have high fat oxidation and this probably only applies to these endurance athletes; I would suspect this high fat oxidation would not be found in other short interval sports i.e. sprinting, football....
ibuprofen provided no reduction in muscle damage/soreness in 29 ultra marathoners. However, LPS, CRP, IL-6, IL-10, IL-8, IL-1ra, GSF, MCP-1, and MIP-1beta were increased in the ibuprofen group. TNF-alpha was unaffected.
event over hydration with under renal excretion can lead to hyponatremia. SIADH and resultant increased ECW is involved. Weight is an adequate means to evaluate--no weight loss and/or weight gain may suggest fluid overload and potential hyponatremia.