Here I go again- another marathon with no long runs under my belt other than the Skagit Flats Marathon 3 weeks ago. I am doing the Bellingham Bay Marathon Sunday.
I actually feel optimistic
- I've done more road than trail running recently, so my pace has been quicker.
- I've done a couple of decent interval workouts since Skagit Flats.
- I've felt ok on a couple of tempo runs- something that I've been neglecting recently.
- I have that marathon under my belt 3 weeks ago that I am convinced will help and not hurt.
- Temperatures should be ok.
One negative that I see is race organizers are serving something called Ultra Replenisher- a drink loaded with electrolytes but only 10 calories per 8 ounces. BIG MISTAKE! Since when do electrolytes enhance endurance performance?? As far as I know electrolytes become more concentrated in the body as you dehydrate/
This study published in the J of Applied Physiology measured "a significant rise in serum sodium and potassium immediately after the marathon run."
"Electrolyte deficiency probably does not occur during marathon running"
-Run The Planet
There is little physiological basis for the presence of sodium in an oral rehydration solution for enhancing intestinal water absorption as long as sodium is sufficiently available in the gut from the previous meal or in the pancreatic secretions (84). Inclusion of sodium (<50 mmol ? l-1) in fluid replacement drinks during exercise has not shown consistent improvements in retention of ingested fluid in the vascular compartment (20,23,44,45). A primary rationale for electrolyte supplementation with fluid replacement drinks is, therefore, to replace electrolytes lost from sweating during exercise greater than 4-5 h in duration (3). Normal plasma sodium concentration is 140 mmol ? l-1, making sweat (~50 mmol ? l-1) hypotonic relative to plasma. At a sweat rate of 1.5 l ? h-1, a total sodium deficit of 75 mmol ? h-1 could occur during exercise. Drinking water can lower elevated plasma electrolyte concentrations back toward normal and restore sweating (85,86), but complete restoration of the extracellular fluid compartment cannot be sustained without replacement of lost sodium (39,70,89). In most cases, this can be accomplished by normal dietary intake (63). If sodium enhances palatability, then its presence in a replacement solution may be justified because drinking can be maximized by improving taste qualities of the ingested fluid (9,25).
-ACSM Position Statement on Exercise and Fluid Replacement